what steels and why

[Vman]

My bad, I was enjoying this steel thing so much it got me thinking. Onward and upward
Vman

[mpukas]

A little late to the party...

Devin - thanks for such an amazing thread! And thanks to Larrin for all of the great info as well. I'm learning so much here. As a blooming knife and sharpening knut, I'm trying to take in and learn as much as I can, and this thread has shed a lot of light on many aspects of steel that I have been pondering.

This thread also touches on many other aspects of knives and sharpening, and I don't want to de-rail this thread (too much), but this quote in particular was great for me;

Lastly, the keener the edge the faster a knife will become dull. The coarser the stone used in sharpening, the longer it will hold that edge. I think that in general most knife nuts over sharpen.

Hoss

I tried to have this discussion on another forum, and I'm not gonna throw anyone under the bus, but I basically got the opposite answer from a couple of diferent sources. It's been my assumpiton that the keener the edge, the more quickly it will dull since the material at the edge is finer. Not that I want to be right or wrong, I just want to understand what's going on. Thanks for this clarification.

I'm gonna copy-paste some of your key posts into a cheat sheet for myself - there's a lot here to digest. I love it! Thanks again for being so open to sharing this info! mpp

[DevinT]

MPP,

This applies to slice cutting and not to push cutting. Serrations always cut longer than a smooth edge, even on a micro scale.

Serrations cut longer because there is simply more edge, the small radiused scallops measured out, are longer than a straight edge.

The other thing that it does is prevent the whole edge from touching the board for example.

Hoss

[eshua]

So the downside of an extreme high grit sharpening style is NOT similar to the downsides you see from sharpening too acutely? eg stability?

Lets put it this way... If you have a few prep items that benefit from a really fine edge: getting the thinnest possible scallions basil ect, And later rough up your edge on a ceramic honing rod when you need to bite into tomatoes or grilled meats. Does this work well for you guys or do you end up with an edge just asking to fail when you polish it out too far?

Trying to work though my bad habits one by one so I'm curious to think of the science of it.

[DevinT]

It is important to match the steel with the heat treatment, sharpening style, cutting habits/preference etc. No one steel or knife can do it all, all the time.

Good edge stability allows for a knife to be sharpened to an acute angle and to a high polish and hold up well. Of course it must have the correct heat treatment also.

Hoss

[Andrey_SPb]

Devin and Larrin,
Thank you very much for very interesting information!

Let me lay out the summary table ordered by Overall Rating (carbon and tool steels are shown in red):



I'm not surprised by low grades of Japanese steel - White (Shirogami) Steel and Blue (Aogami) Super Steel. But, I first saw the real difference between expressed in figures.
I've always read that the difference between them is absolutely not noticeable in actual use. And your table is clear and significant, and for the most important criteria: Edge Holding = 5 - 8, Edge Stability = 8.5 - 5, respectively.
Thank you. This is very interesting!

The list of steels for the study, you wrote in your first post is a very popular and have become very good - ATS-34, S30V, CPM D2, CPM M4. Could you add a table with the results on these steels?

AEB-L steel was the best in your tests. Do not you think that this is due to the fact that you are working with it for a long time and have learned to “squeeze” the most out of this steel?
And that other knifemakers can not get such good results. On the other hand, they can get the best results on steels, which are working for a long time and which well know and feel?
After all, you do testing knives (!), not steels! For knives, except for steel, are important correct hardening, optimal hardness and good geometry.
That is, I want to say that the steel - not a universal concept. Knives made by different knifemakers of the same steel will show very different results!

In conclusion, I would like to draw your attention to two steel, which seem very promising for the manufacture of kitchen knives - AEB-H and the Cru-Wear. The chemical composition of these steels:



Thank you again for a very interesting and useful thread.
And please do not be hard on my English.

[Keith Neal]

Devin, excellent discussion. Very informative.

Since this is one of your knives, can you tell us about the steel in it?

http://www.kitchenknifeforums.com/sh...western-handle

Thanks,

Keith

[El Pescador]

Devin and Larrin,
Thank you very much for very interesting information!

Let me lay out the summary table ordered by Overall Rating (carbon and tool steels are shown in red):



I'm not surprised by low grades of Japanese steel - White (Shirogami) Steel and Blue (Aogami) Super Steel. But, I first saw the real difference between expressed in figures.
I've always read that the difference between them is absolutely not noticeable in actual use. And your table is clear and significant, and for the most important criteria: Edge Holding = 5 - 8, Edge Stability = 8.5 - 5, respectively.
Thank you. This is very interesting!

The list of steels for the study, you wrote in your first post is a very popular and have become very good - ATS-34, S30V, CPM D2, CPM M4. Could you add a table with the results on these steels?

AEB-L steel was the best in your tests. Do not you think that this is due to the fact that you are working with it for a long time and have learned to “squeeze” the most out of this steel?
And that other knifemakers can not get such good results. On the other hand, they can get the best results on steels, which are working for a long time and which well know and feel?
After all, you do testing knives (!), not steels! For knives, except for steel, are important correct hardening, optimal hardness and good geometry.
That is, I want to say that the steel - not a universal concept. Knives made by different knifemakers of the same steel will show very different results!

In conclusion, I would like to draw your attention to two steel, which seem very promising for the manufacture of kitchen knives - AEB-H and the Cru-Wear. The chemical composition of these steels:



Thank you again for a very interesting and useful thread.
And please do not be hard on my English.

I like the idea of your chart but I believe that the data you have used is inconsistent with the results that I have experienced. I have used Devin's 52100 and his mystery carbon side by side and the mystery carbon easily out performs the 52100. They were sharpened the same by the same person. I also think a chart like you have doesn't work because of the inconsistencies in heat treating maker to maker. Taking this further, a maker can vary his heat treat with a certain steel to achieve gains in hardness, toughness or grain size.

[Crothcipt]

hmm I thought he was just making a chart with what was already posted. Nice addition Andrey spb to the thread.

[bieniek]

I like the idea of your chart but I believe that the data you have used is inconsistent with the results that I have experienced. I have used Devin's 52100 and his mystery carbon side by side and the mystery carbon easily out performs the 52100. They were sharpened the same by the same person. I also think a chart like you have doesn't work because of the inconsistencies in heat treating maker to maker. Taking this further, a maker can vary his heat treat with a certain steel to achieve gains in hardness, toughness or grain size.

So what you basically say is that DTs heattreatment was optimal for both of those steels - youve tested, and you managed to get the best out of both of them?