12-28-2017, 11:33 AM
It's not a trivial subject. I mentioned before that GE is concerned about grain growth in nickel alloys during grinding. Grain growth in steels isn't really a problem until you get over 1600 F and spend some time there. I would guess high temperature nickel alloys are even higher.
I have seen microhardness tests that show softening during power sharpening of about 5 points. This is of the edge, not the whole blade. That was also on a simple carbon steel, the easiest to soften. Had I been using those knives for less strenuous activity, I might not have noticed.
I look at it with this in mind. Knife makers and manufacturers spend a lot of time and money on their heat treating processes. I've heard of individual makers adjusting tempering temperatures in 25 degree increments to get their desired result. It is irksome to me that there is that much effort put into it, but final sharpening possibly exposes the steel to a huge range of temperatures.
I have seen microhardness tests that show softening during power sharpening of about 5 points. This is of the edge, not the whole blade. That was also on a simple carbon steel, the easiest to soften. Had I been using those knives for less strenuous activity, I might not have noticed.
I look at it with this in mind. Knife makers and manufacturers spend a lot of time and money on their heat treating processes. I've heard of individual makers adjusting tempering temperatures in 25 degree increments to get their desired result. It is irksome to me that there is that much effort put into it, but final sharpening possibly exposes the steel to a huge range of temperatures.