Few people understand the power of a four-hour dinner. For most Americans, that probably sounds like a nightmare. But in Italy, it’s normal. Expected, even. You settle in. You open a bottle of wine. You talk, and eat, and talk some more. There’s no rush to clear the plates or get to dessert.

Growing up, I was lucky to be part of a family that liked to linger. We’d close restaurants, migrate from the dining room to the patio, and stay out so late the neighbors would gently remind us they had work in the morning. That way of eating—of being, really—has always felt more natural to me. And it’s exactly the kind of spirit cookbook author John Bersani captures in his new book, 20 Amici – 40 Ricette: Friends and Food from the Heart of Chianti.

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It’s not every day you see a former three-Michelin-star chef slinging burgers and homemade potato chips out of a historic red train car. But at Dad’s Luncheonette, the low-key restaurant tucked off Highway 1 in foggy Half Moon Bay, that’s exactly what you’ll find—if you know where to look.

If you pull up, chances are you’ll find Scott Clark—chef, dad, and now cookbook author—chatting with customers, cracking jokes, and running the pass for their short-and-sweet seasonal menu.

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If you’ve ever thrown mushrooms into a pan and watched them shrivel up to almost nothing, you’re not alone. That’s because mushrooms are mostly water. Now what you do with that fact can take your dish from just fine to seriously good.

For example, most people’s first instinct is to salt mushrooms right away. But if you hold off, they’ll crisp up instead of steaming and potentially getting soggy. It’s a small shift, but one that can totally change the outcome and turn a basic ingredient into something seriously craveable.

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A lot of people grow up watching their mom cook—I was lucky enough to be one of them. Even before I could reach the counter, I was trailing behind her in the kitchen, hoping to graduate from taste tester to mixer. And while I’ve since picked up tips from test kitchens, TikTok chefs, and a lot of Ina Garten, the core of my love for cooking will always come back to my mom.

That’s probably why I was so taken with Marjorie Taylor and Kendall Smith Franchini’s story. Their new cookbook, French at Heart, isn’t just a collection of classic French recipes, it’s a celebration of their shared life in food. The mother-daughter duo first made waves when they opened The Cook’s Atelier in 2008, a cooking school, culinary, and wine shop nestled in the heart of Beaune, France. Their classes now sell out months in advance, drawing guests from around the world. And yet, what makes their story stand out isn’t just the stunning Burgundy backdrop or their rustic tartines—it’s the relationship at the heart of it all.

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Welcome to the latest edition of Food52 Founder Amanda Hesser’s weekly newsletter, Hey There, It’s Amanda, packed with food, travel, and shopping tips, Food52 doings, and other matters that catch her eye. Get inspired—sign up here for her emails.

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I have a new (old) book out! My first book—The Cook and the Gardener—about cooking seasonally from a garden and about a crusty old French gardener whom I befriended when I worked as a cook at a château in Burgundy, France, was relaunched yesterday, on the 25th (26th!) anniversary of its original publication in 1999.

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This is a guest post by SherAli Tareen, Professor of Religious Studies at Franklin and Marshall College.

At its core Rajbir Singh Judge’s dazzling monograph Prophetic Maharaja presents an argument for “dwelling in loss” rather than seeking the enticing yet entrapping desires for restoration, recovery, and healing. By writing a “historical narrative that refuses to historicize,” Judge pushes his readers to examine notions of sovereignty and history that the practice of dwelling might make available. Conceptually, through the example of Duleep Singh (d. 1893) and the politics his life and memory make possible, the book seeks to interrupt dominant scholarly notions of historicism and colonial logics of religion and sovereignty, that reappear in varied apparitions in contemporary scholarship as well. It is very rare for a monograph, and even rarer for a first monograph, to offer an example of close and patient reading that rattles deeply held and deeply prized normative assumptions of one’s field of intervention. Judge achieves precisely that. And he does so in multiple ways and registers.

In Panjab Studies, there is a pervasive trend of excavating a redemptive narrative of a Panjabi cosmopolitan ethos that might offer the fantasy of traversing and transcending the alleged juggernaut of religious convictions that according to this view stifle such “cosmopolitan” pasts and futures. The Sikh tradition, under the calculus of this desire for “Panjabiyyat” or “Panjabiness” can either work as a quintessentially hybrid religion that naturally inheres pluralism or as a model for a colonial infested discursive machine that can only be repaired through the prophylactic of secular baptism. Judge entertains none such fantasy. In fact, Prophetic Maharaja conducts a devastating indictment of the politico-conceptual coherence as well as the desirability of the secular quest for Panjabiyyat by presenting a reading of Duleep Singh’s quest for sovereignty that does not seek to resolve, recover, overcome, or redeem any restorative project of liberal redemption and goodness.

Through an analysis both painstakingly layered and theoretically vivacious, Judge masterfully walks his reader through a terrain of political theology populated by visions of sovereignty neither liberal nor secular, but rather nestled in the refusal to exercise the sovereign decision to historicize, humanize, and heal any alleged ruptures of history. Judge’s analysis of Duleep Singh’s attunement to the loss and possibility of sovereignty propels the reader to confront and wrestle with a grammar of life that is not driven by or available for secular projects of dividing that life into binaries like religion and culture, state and society, plural harmony and exclusivist bigotry. Life, Judge teaches us, taking a cue from anthropologist Talal Asad, is “essentially itself.”

One of the great lessons of this book that I found particularly striking and productive concerns its theorization of loss and its simultaneous recognition that loss escapes and exceeds any neat theorization. Judge is at his most brilliant and intellectually courageous during moments in this book when he meditates on the aporias of his own encounter with the conceptual constitution of his project. And remarkably, and again in a rare achievement, these are precisely the moments when his argument is most piercing and compelling. His discussion of loss is a great example of this. As Judge writes very early in the book (in its Introduction), signposting an analytical attitude and conviction he sustains throughout the monograph: “rather than provide a new theorization of loss-which cements a relation to loss-this book endeavors to reckon with the powerful resources that work on loss, such as mourning and melancholia, and what they have already provided.” Judge continues, in a flash of utter brilliance, “I contend with loss instead of transcending it through recovery [emphasis mine]…I do not tie a thread throughout the text that provides an adequate answer to loss because there might not be any answer to it. In this sense the book does not provide a theorization of loss but dwells in the various rhythms of loss. My goal is not to recognize loss and provide it taxonomic space but to sit with losses as they appear, disappear, and reappear throughout the text” (p. 13). This mini paragraph I have just cited represents a moment of tremendous significance in the study of South Asian History and Religion. Note, in the interest of careless readers who will rush towards the inconsiderate gesture, all too pervasive among historians of a certain ilk, to dismiss or undermine careful theoretical interventions as Judge’s here as convoluted high theory. Note particularly that dwelling, in Judge’s account, as both an analytical concept and as a mode and practice of life, is anything but passive inactivity. Exactly to the contrary, dwelling represents that aggressive commitment to a politico-conceptual ethic of refusing to repair and overcome loss through secular gestures of managing and healing the violence of history.

Dwelling in loss, instead of activating the secular instinct of historicizing, humanizing, and supposedly transcending loss makes possible a horizon of the political that comes to live with rather than attempt to overcome the aporias of life. Judge’s invitation to his readers to “sit with losses as they appear, disappear, and reappear” in the passage of a text or in the passage of history is I believe a profound call for suspending sovereign confidence in compensating for loss and treating the wound of historical contingency through the fantasy of historicist rigor, of returning life to its immanent materiality. What sort of politics and possibilities of sovereignty might become available by dwelling in loss, by sitting with rather than treating with the prophylactic of secular historicism the vertigo of historical conjunctures such as the one involving the loss, renewal, and diffusion of Duleep Singh’s aspiration for sovereignty? In asking and addressing this question, Judge successfully offers pathways for recognizing and exploring the political power and philosophical sophistication of imaginaries of sovereignty, like Duleep Singh’s, that are otherwise conveniently though perniciously catalogued as sorry tragedies of a colonized subject. Making Duleep Singh’s example speak back to and interrupt the alleged tragedy of his quest for sovereignty, Judge undertakes a critically important endeavor of decolonizing both colonial and contemporary secularist models of South Asian history populating the Western academy. This forum brings together outstanding scholars, conducting theoretically cutting edge critiques of secular power from multiple disciplinary perspectives, to engage, wrestle with, and celebrate a book with major ramifications and consequences in the study of religion, history, philosophy, and South Asia. The Prophetic Maharaja is in many ways a model and master seminar in bringing together invasive attention to the particularity of an archive and theoretical reflection that paves as well as shifts the terrain of multiple fields of knowledge simultaneously.

SherAli Tareen is Professor of Religious Studies at Franklin and Marshall College and currently a Patricia Crone member in the School of Historical Studies at the Institute for Advanced Study in Princeton NJ for the academic year 2024-25. His book Defending Muhammad in Modernity (University of Notre Dame Press, 2020) received the American Institute of Pakistan Studies 2020 Book Prize and was selected as a finalist for the 2021 American Academy of Religion Book Award in the Analytical-Descriptive Studies category. His second book is Perilous Intimacies: Debating Hindu-Muslim Friendship after Empire (Columbia University Press, 2023) which was selected as a finalist for the 2024 American Academy of Religion Book Award in the Textual Studies category.

Rajbir Singh Judge is Assistant Professor in History at California State University, Long Beach. Prophetic Maharaja: Loss, Sovereignty and the Sikh Tradition in Colonial South Asia was published in 2024, and over the next few weeks we have a series of contributors who’ll be offering their reflections, followed by a response from Rajbir. I’ll update this post with links to the other posts as they’re published:

Introduction by SherAli Tareen

LL Hodges, ‘Claustrophobic Archive‘

Amaryah Armstrong, ‘Black Internationalism, the Black Prince, and the Pressures of History‘

APS, ‘”What this means I do not know”: Loss and Rumours of Loss‘

Samaah Jaffer, ‘The Contention of Mourning‘

Marika Rose, ‘A Matter of Fantasy‘

Satbir Singh, ‘Dandy (de)livery‘

Basit Iqbal, ‘Non-redemptive Narration‘

Response by Rajbir 

The following is a collaboration project between myself and Malachi Chou-Green. He obtained the Vanadis 60, did some heat treating experiments, and also did metallography including some fancy electron microscopy. He also heat treated and machined the CATRA knife that I tested. His original experiments were published some time ago on his Patreon, so if you want to see what he is up to I recommend visiting his Patreon page and becoming a supporter.

Video

The following information is also available as a video:

Background of Super High Speed Steels and Vanadis 60

High speed steels with greater than 2% vanadium for wear resistance were developed in the late 1930s  and early 1940s leading to M4 high speed steel and T15 high speed steel. I have written a short article on the history of M4 steel, and my recent book The Story of Knife Steel has a more etensive history if you are interested in reading further. Previously vanadium was found to lead to very hard carbides for very high wear resistance but when the additions exceed ~2% the steel would not harden. The breakthrough in the 1930s was that they learned that more carbon was necessary in conjunction with the vanadium, to compensate for the carbon that was being tied up in the vanadium carbides. However, vanadium was still limited to about 4-5%, otherwise the carbides would become too large and the steel would fracture during forging and/or rolling.

Another development occurred in the early 1960s when it was discovered that greater control over carbon content and cobalt addition could be used to make high speed steels that could be heat treated to 70 Rc. Several steels were patented within only a few years by different companies, with the most common being VASCO Hypercut patented in 1963, given the standard designation M42. You can read more about the history of these steels in this article. The compositions of these steels are shown in bold, and the older lower carbon versions of each are shown below each of the bold compositions in the “M40” series.

Around the same time Crucible developed powder metallurgy technology which was capable of creating finer microstructure in tool steels by avoiding the slow solidification associated with conventionally cast alloys. They began producing these steels for commercial scale in 1970. You can read more about how powder metallurgy works and its history in this article. At the beginning Crucible used this technology to improve performance of existing steels like M2 or T15, but they also began designing steels specifically for the technology. The first of these was CPM Rex 76, patented in 1972, which was a high hardness high speed steel with 3% vanadium.

Shortly after Crucible introduced their powder metallurgy technology, Stora in Sweden introduced their own version of the technology. This led to a legal battle that Crucible would eventually win, requiring Stora and Uddeholm to pay fines. Stora developed a higher vanadium 70 Rc high speed steel called ASP 60 which was introduced by 1975. It had 6.5% vanadium for higher wear resistance than Rex 76. Uddeholm purchased Stora in 1976. In 1978 Crucible published results of their experiments [1] comparing Rex 76 and ASP 60 which they claimed showed that higher than 3% vanadium did not lead to better performance in high speed tools. They also made a 6% vanadium version of Rex 76 and they demonstrated that it had no better tool life than the standard 3% vanadium version.

J.H.G. Stake of Uddeholm was not happy with these claims. He said [1], “I represent the firm that sells the steel mentioned which is available commercially, the ASP steels by the ASEA-STORA process. It is very difficult to comment on the slides shown here regarding the comparison between ASP 60, Rex 76, and Rex 76 with 6% vanadium. The main reason is that the trials have been done without any coolant and that is very unusual in commercial application in general practice. We prefer to go to the toolmaking industry and have the trials made there.”

Uddeholm would eventually begin selling ASP 60 under the name Vanadis 60 instead, and Erasteel which also had historical connections to Stora, would sell it under the name ASP 2060. Both have the same composition. Despite Crucible’s earlier claims about 3% vanadium being as much as is necessary, they would later release higher vanadium versions of Rex 76. The 9.5% vanadium version called Rex 121 was released in 1998 [2]. The 5% vanadium version is known as Rex 86 (Zapp sells it as Z-Max) which was released in 2005 [2]. Other high vanadium 70 Rc powder metallurgy high speed steels would be released by other companies, many of which are shown below:

For more exciting knife steel and tool steel history, plus a history of the modern knife industry including custom knives, high-end production knives, and Damascus, see my book The Story of Knife Steel.

Composition and Microstructure

As mentioned above ASP 2060 (Erasteel) and Vanadis 60 (Uddeholm) are identical in composition. They have molybdenum and tungsten (and to a lesser extent chromium adn vanadium) added for “hot hardness,” the ability for a steel to maintain its hardness at high temperatures. This is important for machining operations where the tools are run at “high speed” and thus heat up due to friction. Hot hardness is created through a phenomenon called “secondary hardening” where the precipitation of very tiny carbides causes the steel to further harden when tempering at high temperatures, which you can read about in this article. The vanadium content of Vanadis 60 is relatively high at 6.5% for wear resistance. Cobalt is added to further improve hot hardness by affecting how the carbides form in secondary hardening (as opposed to forming carbides such as molybdenum and tungsten). You can read more about cobalt in this article.

The toughness and wear resistance of high speed steels is largely controlled by the carbides. Where increasing carbide volumes and sizes tend to decrease toughness, increased volumes of harder carbides increase wear resistance. Each of the above mentioned steels forms some M6C carbides (tungsten/molybdenum carbides) and MC carbides (vanadium carbides). With this in mind, vanadium carbides are generally more desirable because they are harder and smaller than the tungsten/molybdenum carbides. Therefore the vanadium carbides are less detrimental for toughness while also contributing more to wear resistance.

Below I have calculated carbide contents using Thermo-Calc for Vanadis 60, Rex 86, Maxamet, and Rex 121. Importantly these are “equilibrium” calculations, meaning they assume an infinite hold time. Each is calculated for the austenitizing temperature that was used for the CATRA knife coupons I tested.

So based on total carbide volume alone we would expect Maxamet to have the highest toughness (it has the lowest carbide volume), followed by Rex 86, Vanadis 60, and finally Rex 121. Maxamet and Vanadis 60 have similar MC content but Vanadis 60 has higher M6C, so we would expect Vanadis 60 to have higher wear resistance than Rex 76, Rex 86, and Maxamet, but less than Rex 121.

Below are the micrographs for these steels to compare with Malachi’s Vanadis 60 micrograph.

Maxamet austenitized from 1975°F

Z-Max/Rex 86 austenitized from 2150°F

Rex 121 austenitized from 1925°F

Looking at the micrographs above, the carbide volume of Vanadis 60 appears to be similar to that of Maxamet, but the carbides are a bit smaller. Z-Max has a similar carbide size to Maxamet but a lower carbide volume. Rex 121 has the most carbide and the largest carbides as expected based on its composition.

We measured the carbide volumes of each steel using a simple method called “point counting” to compare with the Thermo-Calc estimates. The total carbide volume measured was significantly lower in Vanadis 60 and Rex 86/Z-Max than the equilibrium estimate. This is relatively unusual as equilibrium carbide volume estimates ten to underpredict the true carbide volume because it assumes an infinite hold time at austenitization temperature. Maxamet and Rex 121, both had carbide volume a few points above the Thermo-Calc equilibrium estimate which is more typical.

Malachi also took scanning electron microscope (SEM) micrographs of Vanadis 60 austenitized at 1900 and 2125˚F using the “backscatter” imaging technique where contrast is partially generated from composition differences within the sample. Heavier elements scatter more electrons back into the detector leading to bright areas. Thus vanadium carbides show up as grey while the tungsten/molybdenum carbides are white, due to the relative atomic weights of the carbide forming elements (V < Mo < W).

Vanadis 60 austenitized from 1900°F

Vanadis 60 austenitized from 2125°F

Using different colors he point counted the volume of M6C, and total carbides and compared them against the Thermo-Calc predictions. The measured M6C (tungsten/molybdenum) carbide volume was lower than Thermo-Calc, while the measured MC (vanadium) carbide volume was high. So it appears that Thermo-Calc is overpredicting M6C carbide and underpredicting MC carbide stability in Vanadis 60. Perhaps similar differences are leading to the overprediction of carbide volume in the Z-Max, and imply that the MC carbide volume of Z-Max may also be greater then Thermo-Calc predicts. This could partially explain why Z-Max preformed better in CATRA testing than my equation suggested it would.

Hardness and Heat Treating of Test Coupons

The ASP 2060 datasheet has a better heat treatment hardness chart than the Vanadis 60 datasheet so I have included it below:

Malachi reported that he got 70.5 Rc with 2125-1000°F (1160-540°C) and 68.8 Rc with 1900-1000 (1040-540°C). He also austenitized the CATRA coupon from 2025°F (1100°C) which I tempered at 1000°F (540°C) for a hardness of 68.4 Rc. Malachi reported to me he later measured the temperature of the furnace he was using and found it to be reading too high, (thus the furnace temperature was lower than 2025°F), which may explain why the hardness was lower than his previous 1900-1000 coupon. I also heat treated toughness coupons using 2025-1000°F and the resulting hardness was 69.0 Rc. As expected Vanadis 60 is capable of very high hardness.

Edge Retention

To test the edge retention, Malachi heat treated and machined the CATRA knife for testing. I performed the final sharpening and tested for slicing edge retention:

Somewhat surprisingly the resulting edge retention was only slightly higher than Z-Max after compensating for hardness, and was significantly below Maxamet. This was puzzling because Maxamet and Vanadis 60 have similar vanadium and carbon, while Z-Max is somewhat lower in both elements.

Based on our carbide volumes measurements, both the Maxamet and Vanadis 60 CATRA knives should have carbide volumes around 22%. However, as discussed previously Thermo-Calc seems to underpredict vanadium carbide and overpredict tungsten/molybdenum carbides in Vanadis 60 so perhaps the same thing is happening in Maxamet. This could be compounded by the difference in “tungsten equivalent” contents between the steels. Tungsten equivalent is calculated by multiplying the molybdenum content by two and adding it with the tungsten content, to account for the difference in atomic weight between the two. Since tungsten and molybdenum form M6C carbide, steels with higher tungsten equivalent contents are more prone to M6C carbide formation. The tungsten equivalent of Maxamet is 13% and Vanadis 60 is 20.5%, so perhaps the structure of Maxamet is mostly MC type carbides. We would need to do backscatter imaging with the Maxamet to confirm if there is indeed more MC carbide in the Maxamet than Thermo-Calc predicts.

Toughness

I heat treated and machined the Vanadis 60 charpy toughness coupons using the same 2025-1000°F heat treatment as the CATRA coupon, resulting in 69 Rc:

As expected by the very high hardness (69 Rc) and the relatively high carbide volume (~22%), the toughness was fairly low at 2.7 ft-lbs. Zooming in on the high hardness steels I added a trendline showing the approximate change in toughness with hardness for CPM T15, CPM Rex 45, CPM Rex 76, and Z-Max. Vanadis 60 looks like it has toughness a notch down from those steels while being more in line with Maxamet. This makes sense given that Maxamet has about the same carbide volume while those other steels have have lower carbide volumes ranging from 14-18%. Carbides are very hard particles and so they are detrimental to toughness. You can also see that as hardness goes up the difference between the highest and lowest toughness steels decreases. So at 61.5 Rc we have measured values all the way from ~4 ft-lbs to 45 ft-lbs. But at 67 Rc it only ranges from 2.6 to 5.9 ft-lbs. Thus it seems the higher the hardness the less influence the carbides have on the measured toughness.

One interesting thing to note is that the spread in toughness was particularly high for the Vanadis 60 coupons, coming out at 3.4, 2.1, and 2.6. This spread is especially apparent when we look at the 95% confidence intervals of the toughness measurements of other high hardness steels shown below. I am not sure what led to the variation, perhaps it was merely chance.

While it is hard to predict toughness trends, it seems that at the same hardness we would expect Vanadis 60 to have toughness between that of Z-Max and Maxamet, leaning more towards the Maxamet end of the spectrum. As mentioned above, the Vanadis 60 and Maxamet samples tested have similar carbide volumes but Vanadis 60 has finer carbides. Usually, we would expect finer carbides to lead to better toughness, however in this case the improvement seems somewhere between quite small and non-existent. Toughness in steels is determined by two factors, crack initiation and crack growth. In tool steels, the ductility is low enough that usually, crack initiation is the controlling factor, in these cases smaller carbides are harder for cracks to initiate on, leading to better toughness. However, crack growth is generally easier with a smaller interparticle distance (the distance between carbides). So while crack initiation is usually the controlling factor, maybe as the carbide volume increases, improvements to toughness caused by finer carbides are mitigated by their risk of increasing crack propagation.

Summary and Conclusions

Our testing of Vanadis 60 found toughness about where you would expect given its high carbide volume and very high hardness, and as expected it is capable of very high hardness and has excellent wear resistance. However, the slicing-edge retention was lower than we predicted based on the composition, testing more similarly (but still a bit higher) than Z-Max rather than the more compositionally similar Maxamet. We also explored the interesting history of Vanadis 60; while several other 5%+ vanadium 70 Rc powder metallurgy steels have come since then, Vanadis 60 was the first.

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[1] Kasak, A., and E. J. Dulis. “Powder-metallurgy tool steels.” Powder Metallurgy 21, no. 2 (1978): 114-123.

[2] https://www.crucible.com/Products.aspx?c=7

The post Testing Super High Speed Steel Vanadis 60 appeared first on Knife Steel Nerds.

Thank you Patreon Supporters!

Thank you to my Patreon supporters who help make these studies happen. Patreon funds were used for purchasing two ultimately useless knives, and some steel. Patreon supporter Marcus Ho even sent me some steel all the way from China which also ended up not working out. And I used Patreon funds to pay Shawn Houston (also a Patreon supporter) to do microscopy and grind two CATRA knives for me. So when I say that Patreon makes the study happen I don’t mean in an abstract sense. If you want to help fund more knife steel research please come join us on Patreon where you can get articles and videos early. Or if you sign up for the highest tier you can even get a sweet Knife Steel Nerds mug.

Video

Video version of the following information:

History of 8Cr13MoV/8Cr14MoV

To cover the history of 8Cr13MoV we have to go back to Japan, or even further back to Europe. Hitachi in Japan came out with their own stainless tool steels called “Gingami” meaning “silver paper” with three different designations. All three of these steels were copies, or nearly so, of stainless steels available in Europe. They were released somewhere in the 1933-1951 time period. In 1960 Fukami Steel Company was founded in Japan and they introduced AUS-4 and AUS-6 in 1968. AUS-4 was a 420/420HC type steel and AUS-6 was similar but with higher carbon and a small molybdenum and vanadium addition. AUS-6 was very similar to Gingami 2, and also other European steels such as Sandvik’s 12C27. AUS-8 was introduced in the 1970s which was AUS-6 with increased carbon up to ~0.8%. AUS-6 and AUS-8 became very common in Japanese factory knives, such as Kershaw’s imported knives introduced in the late 1970s. You can read more about all of this history (including citations) in my book The Story of Knife Steel.

8Cr13MoV, also called 8Cr14MoV, is a generic Chinese designation for AUS-8. They have identical composition. The naming scheme is pretty self-explanatory, I think, but maybe it makes sense to describe it explicitly. The first number designates the carbon content, so “8” refers to ~0.8% carbon, Cr13 means 13% chromium, Mo means a small molybdenum addition, and V means a small vanadium addition. So 7Cr17 means 0.7% carbon and 17% chromium, 9Cr18 means 0.9% carbon and 18% chromium, and 9Cr18MoV is the same with molybdenum and vanadium. Another steel that seems to be building in popularity is 10Cr15CoMoV which is 1% carbon, 15% Cr, plus cobalt, molybdenum, and vanadium; a copy of Takefu’s VG-10. I have heard these designations sometimes referred to in a derogatory way as “Chinese alphabet soup” though I think it should be known that these designations are a slight modification of an earlier European designation system. For example, 9Cr18MoV has existed for a long time in Europe as X90CrMoV18, also referred to by another European designation system as 1.4112. This is the European version of 440B which has some small differences with the American AISI 440B, such as higher chromium (18 vs 17%) and molybdenum (1-1.3% vs <0.75%). 7Cr17 is the same as AISI 440A. To the average consumer I’m sure all of the numbers are somewhat mystifying and steel names tend to be more memorable.

I don’t know when 8Cr13MoV was first used, but it was first advertised in knives by Spyderco in 2005 with their new “byrd” line of knives produced in China. Spyderco had requested their new knives be produced in 440C and tests of the knives were positive. However, Sal Glesser requested they check the composition of the steel and found it to be identical to AUS-8, not 440C as the factory told them. They learned the steel was designated as 8Cr13MoV in China and advertised the knives as such [1]. There is no distinction between 8Cr13MoV and 8Cr14MoV, all published compositions I have been able to find are the same, apart from Spyderco’s composition table which lists the chromium content only as 13.0%, rather than other published ranges I have found which show 13-14.5% chromium.

My History with 8Cr13MoV/8Cr14MoV

Because of how common AUS-8 and 8Cr13MoV knives are, I was interested in testing the steel for some time. However, despite how common it is in factory knives, obtaining individual bars of it was actually pretty difficult. Japanese and Chinese steels are pretty difficult to obtain in the USA to begin with, as most of it is sold directly to knife companies in their respective companies. Furthermore, because they are known as “budget” or even “low end” steels custom knifemakers in the USA are not exactly clamoring for it so the knife steel supply companies were not trying to get any.

My first solution was to purchase two “Schrade Leroy” choppers made in 8Cr13MoV which have large flat areas. This would allow me to anneal (soften back to the steel factory state) the steel and then heat treat it how I want. The flat areas mean I could make steel coupons for testing such as toughness coupons and potentially CATRA knives. That gives me control over the heat treating and geometry of the steel so I am not limited to available knives.

The knife had easily removable handles so I annealed one of them and posted to my Patreon that I would soon be testing the steel. One of my Patreon supporters, Marcus Ho, contacted me and offered to purchase some 8Cr13MoV bar stock so I wouldn’t have to use my more complicated method for obtaining the steel. Marcus is a knifemaker in Hong Kong so he had experience with sourcing steel in China. You can follow him on instagram under his company name HK.Knifeworks. He sent me a bar of steel along with a very official composition certification.

So I set the Schrade knife aside and started working with the new bar of steel. I started with developing hardness curves with different temperatures, which looked about where I expected them to be. But then I tested the toughness and it was worse than I expected, being more in line with 1% carbon stainless steels like 154CM or 440C. I then looked at the microstructure and it had too much carbide in it, looking again like 154CM or 440C. So I tested the composition of the bar and it was indeed 440C. This was an ironic reversal of the situation that Spyderco saw with their byrd knives. I was so disgusted with this whole debacle and all of the time I had wasted on a bar of 440C that I stopped working on the steel altogether.

More recently I learned that Aus Maker Supplies in Australia had obtained some 8Cr14MoV to sell to knifemakers and I asked if they could send me some. This time I actually got a bar of real 8Cr13MoV/8Cr14MoV and I am happy to report that I have actually tested the real thing.

Hardness

I tested the heat treatment of 8Cr14MoV with a range of austenitizing temperatures after soaking for 15 minutes, plate quenched, and tempered at 300 or 350°F. For half of them I used a cryo step in liquid nitrogen after the quench but before the temper. I didn’t find any published information on heat treating the steel, but Aichi has a recommendation for AUS-8 of 1050°C austenitize and 180°C temper (1925°F/350°F).

As with any steel, cryo led to higher hardness, and a higher austenitizing temperature from which peak hardness was obtained. Without cryo peak hardness was from 1950°F, so the recommendation for AUS-8 of 1925°F is good I think. It is dangerous to heat treat close to the peak hardness, because austenitizing above the peak means that there is excess “retained austenite” dropping the hardness which leads to worse performance. These are small coupons so in an industrial environment with slower quenching speeds the hardness may be somewhat lower. 61 Rc with the 1925-350 heat treatment is pretty good. Also the steel can achieve relatively high hardness, up to 64.5 Rc with a low 300°F temper. A more conservative 350°F you can still get into the 62.5-63.5 Rc range.

Microstructure

8Cr13MoV has a generally fine carbide structure but has many larger carbides mixed in. Sandvik and Uddeholm razor steels 13C26, 14C28N, and AEB-L seem to have about the limit in terms of carbon and chromium content before large carbides become unavoidable without more expensive manufacturing such as powder metallurgy. I have AEB-L below as a comparison to see what I am talking about, along with the higher carbon 440C and VG10 which have even larger carbides.

8Cr13MoV 1925°F-350°F Area 1

8Cr13MoV 1925°F-350°F Area 2

8Cr13MoV 1950°F-350°F Area 1

8Cr13MoV 1950°F-350°F Area 2

AEB-L

440C

VG10

In terms of grain size we also did an etch to reveal prior austenite grain boundaries. It is notoriously difficult to reveal grain boundaries so they are somewhat difficult to see. However, it is apparent that there was some grain growth with 1950°F when compared with 1925°F.

8Cr13MoV 1925°F-350°F

8Cr13MoV 1950°F-350°F

We also observed broader “segregation” and carbide stringers on a macro scale, especially in the 1925°F CATRA knife, which is shown below with two different angles. We also had a surface defect from the carbide stringers, which is seen as a shadow in the darker of the two. This happens when a carbide stringer is big enough that it breaks out during grinding. Segregation and carbide stringers are not unique to 8Cr13MoV, they are relatively common with ingot cast steels (as opposed to powder metallurgy). This is especially the case with higher carbon conventional steels like 440C and 154CM. The carbide stringers are parallel to the edge, perpendicular to the “grind lines.”

Toughness

For toughness tests I heat treated two conditions: 1925-350°F without cryo (roughly matching factory knife heat treatments), and 1950-350°F with cryo (higher hardness and closer to a custom heat treatment). These resulted in about 60 Rc and 62 Rc, respectively.

As expected based on the presence of some larger carbides, the toughness of 8Cr13MoV is significantly lower than AEB-L, 14C28N, LC200N, and Nitro-V. However, the toughness of 8Cr13MoV is still better than most other conventional high carbon stainless steels like 440C, VG10, and 154CM. It is also better toughness than most powder metallurgy stainless steels, even Vanax, XHP, and S35VN (though not MagnaCut). So overall 8Cr13MoV/8Cr14MoV has pretty good toughness despite its reputation as a low end steel. AUS-8 would also be similar.

CATRA Edge Retention

For CATRA edge retention coupons I used the same heat treatments, though they both came out slightly harder at about 61 and 62.5 Rc. However, one interesting thing is that the 1925-350°F heat treatment, the softer of the two, measured higher for edge retention, with an average after four tests of 395 mm of cardstock cut in the CATRA test. The 1950-350°F instead measured 376 mm. The 1950 coupon tested very consistently with values of 370, 382, and 377 mm. The 1925, however, seemed to do better the more I retested it with 357, 399, 389, and 429 mm. After puzzling over this I think the reason is that we had more carbide stringers near the edge with the 1925-350°F CATRA coupon, as discussed in the microstructure section. So perhaps what happened is that I was sharpening into a more carbide-rich region leading to the higher values. This is part of the inconsistency of conventionally cast steels, leading to more variable microstructure and therefore properties. Powder metallurgy steels are typically more consistent. To be kind to 8Cr13MoV I plotted only the higher 1925 coupon on the chart below:

The steel tested about where it was expected to fall, a bit above the lower carbon AEB-L and Nitro-V, but below higher carbon steels like 440C, VG10, and 154CM. When compensating for hardness it did very similar to LC200N and 14C28N. Both of those steels (LC200N and 14C28N) tested a bit better than I expected based on their composition, as I expected them to be closer to AEB-L and Nitro-V. So I am curious if I were to test three knives if they would still end up where they did (as opposed to resharpening the same knife), or if there are other features of those steels that cause them to test a bit higher. But we are talking relatively small differences, it’s not as if the steels were competing with S30V.

Comparison with My Original Ratings

I had been running Knife Steel Nerds for a few years before I finally did my ratings of knife steels. I wanted to have experimental results before rating them. One of the few steels I gave a rating for without testing it was 8Cr13MoV/AUS-8, in part because it is so common and many people asked me to rate it. So I gave my best guess in the table which I reproduced below:

I guessed that the toughness would be a “6,” in between 5’s like Vanax and S35VN and the 7 of MagnaCut. And indeed the steel ended up in between those. The edge retention I gave a “3,” the same as AEB-L, LC200N, and 14C28N, and it tested similarly to those steels. So I pointed all that out to pat myself on the back for my predictive abilities based on educated guesses and everything I’ve learned about steels over the years. It’s fun to brag sometimes. I didn’t test corrosion resistance of the steel, it gets a 7 because it is largely a carbon-chromium steel (with a little Mo and V), and so should fall in line with other steels of similar carbon-chromium ratio. If everyone is really clamoring for corrosion resistance tests of these types of steels I will think about doing another round of salt spray tests.

Summary and Conclusions

8Cr13MoV started as a copy of the Japanese steel AUS-8. I told the complicated and boring story of why I have had such a hard time getting this steel so I could actually test it. I think the obtainable hardness of the steel is pretty good, it can be heat treated up to 64 Rc or so, and is very easy to heat treat into the 60-61 region without cryo and 62-63 Rc region with cryo. The 1925-350°F (1050-180°C) heat treatment recommended by Aichi for AUS-8 is a good starting point for a cryo-free heat treatment. With cryo you can austenitize up to the 1975-2025°F range for high hardness if desired. 300°F is as low as I typically recommend tempering, though 350°F gives more balanced properties. The microstructure is disappointing if you are comparing to AEB-L and 14C28N though looks pretty good when compared with higher carbon conventional steels like 440C, VG10, and 154CM. The toughness was better than those 1% carbon steels but not as good as the fine AEB-L and 14C28N, but quite respectable either way. The edge retention wasn’t much better than AEB-L for the toughness deficit, but with the good hardness 8Cr13MoV can have it isn’t too bad. Luckily for me I didn’t have to modify the ratings I had already given the steel in each category because my predictions were pretty good. If you are in Australia 8Cr14MoV/8Cr13MoV is a good low cost steel to purchase from Aus Maker Supplies. And if you are buying knives in the steel you don’t need to worry about the steel itself being “junk,” there are a lot worse choices. Of course that assumes the knife company is heat treating it properly.

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[1] https://forum.spyderco.com/viewtopic.php?f=2&t=14579&p=140419

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I drove my family all the way out to Bethlehem, PA to film a video about steel history so I hope you watch it. Read about my knife steel history book here: https://knifesteelnerds.com/2023/05/09/new-book-the-story-of-knife-steel-innovators-behind-modern-damascus-and-super-steels/

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