Ok, let me start by saying I'm not a metallurgist--this is just the result of some research (poking around on the web, if you prefer) and my thoughts.
In my other thread about stainless steel knives, the discussion prompted me to start thinking about the topic and I've spent some time looking at various charts that show the composition of common knife steels. Naturally, some of that time was spent comparing the carbon content of "carbon" steels, "tool" steels and "stainless" steels.
I don't understand the details, but I believe that at one time, the carbon content of stainless steel was limited due to issues related to the high chromium content that defines stainless steel. If someone has a good explanation of that limitation, I would really like to hear it.
At any rate, I believe that some of the new techniques for making stainless steel alloys have bypassed this limitation resulting in stainless steels that have very high carbon content.
For example, CTS-XHP has a carbon content that exceeds that of 1095 carbon steel, and that actually matches the carbon content of D2 tool steel. Some stainless alloys, like ZDP-189 actually have carbon content that far exceeds the common "carbon steels" and is only matched by a few tool steels.
Looking at hardness numbers, it appears that a lot of the premium stainless steels actually outperform all the conventional carbon steels and even many tool steels.
So...
Does it really make sense to keep talking about carbon steel vs stainless steel like there's a practical difference between the carbon content that gives the carbon steels hardness advantage? Because it appears that both in terms of carbon content and hardness, there are many premium stainless steels that directly contradict that pretense.
It appears (to my admittedly amateur eye) that when the real differences between carbon steel and stainless steel are evaluated, the only real benefits of common carbon/tool steels, are ease of sharpening, cost, and perhaps ease of forging. In all of the other performance areas, as far as I can tell, the premium stainless steels have a decided advantage.
Thoughts?
In my other thread about stainless steel knives, the discussion prompted me to start thinking about the topic and I've spent some time looking at various charts that show the composition of common knife steels. Naturally, some of that time was spent comparing the carbon content of "carbon" steels, "tool" steels and "stainless" steels.
I don't understand the details, but I believe that at one time, the carbon content of stainless steel was limited due to issues related to the high chromium content that defines stainless steel. If someone has a good explanation of that limitation, I would really like to hear it.
At any rate, I believe that some of the new techniques for making stainless steel alloys have bypassed this limitation resulting in stainless steels that have very high carbon content.
For example, CTS-XHP has a carbon content that exceeds that of 1095 carbon steel, and that actually matches the carbon content of D2 tool steel. Some stainless alloys, like ZDP-189 actually have carbon content that far exceeds the common "carbon steels" and is only matched by a few tool steels.
Looking at hardness numbers, it appears that a lot of the premium stainless steels actually outperform all the conventional carbon steels and even many tool steels.
So...
Does it really make sense to keep talking about carbon steel vs stainless steel like there's a practical difference between the carbon content that gives the carbon steels hardness advantage? Because it appears that both in terms of carbon content and hardness, there are many premium stainless steels that directly contradict that pretense.
It appears (to my admittedly amateur eye) that when the real differences between carbon steel and stainless steel are evaluated, the only real benefits of common carbon/tool steels, are ease of sharpening, cost, and perhaps ease of forging. In all of the other performance areas, as far as I can tell, the premium stainless steels have a decided advantage.
Thoughts?
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