Anybody want to guess what this is?

Yes, I did etch this blade in ferric chloride, though the pattern was visible before etching. In fact, I first noticed it when I was rough grinding, before hardening.
The pattern didn't change at all throughout the heat treating.
Here's what I did to this blade:
It's Badger O1 from Timken. It was 3/8" thick, and I forged it down with my power hammer to about 7/32". I would guess the forging temp as 1700-1900
I decided not to normalize, since the data sheet says not to; I just wanted to try it once. The blades warped a little, so I think I'll normalize in the future...
I sphereoidized the blades, ground them, austenitized at 1475 for ten minutes, tempered several times, hunting for the hardness I was after, ended up at 475, with a hardness of 59-60ish.

I saw the same thing in some H13 I forged into a blade once. (lousy blade steel BTW :D)

I'll try to get a photo of the pattern on un-etched steel, but doubt it'll work.
 
I think Phillip said there was no "forge welding" he didn't mention forging alone. Alloy banding is very impressionable, you can stamp shapes into it and then forge flat with no grinding and still get quite a bit of patterning from it. I am sure the much used image of the banded 52100 that I patterned my intials into can resurface again.

There are downsides, it is a very segregated condition and in general steel sees the most benifits from homogenous conditions. With all the carbides locked up in those bands there is very little left to support the ferrite matrix, thus such blades are very ductile- the upside is that they will bend all day, the downside is that they will bend all day, and with MUCH less coaxing than a blade with a well tempered, homogenous condition.

They will saw rope like crazy because the carbide depleted ferrite will wear away at a differential rate than the bands, making an edge that microscopically looks like the smile of the tobacco chewing white trash gal down the road. Yet you may not like how that same edge holds up against hitting a target with more resistance. I have found that hard cardboard and wood sort of smooth over and smear such edges. But if Phillip did not intentionally sgregate thigns as much as possible, it may still perform quite well.

O1 is very susceptable to banding, it is the alloy that I get the most "what are these funy lines in my steel" questions about. Many folks trying to speroidize or that drift a bit in their normalizing cycles end up with striking banding.
 
Kevin R. Cashen said:
I think Phillip said there was no "forge welding" he didn't mention forging alone. Alloy banding is very impressionable, you can stamp shapes into it and then forge flat with no grinding and still get quite a bit of patterning from it. I am sure the much used image of the banded 52100 that I patterned my intials into can resurface again.

There are downsides, it is a very segregated condition and in general steel sees the most benifits from homogenous conditions. With all the carbides locked up in those bands there is very little left to support the ferrite matrix, thus such blades are very ductile- the upside is that they will bend all day, the downside is that they will bend all day, and with MUCH less coaxing than a blade with a well tempered, homogenous condition.

They will saw rope like crazy because the carbide depleted ferrite will wear away at a differential rate than the bands, making an edge that microscopically looks like the smile of the tobacco chewing white trash gal down the road. Yet you may not like how that same edge holds up against hitting a target with more resistance. I have found that hard cardboard and wood sort of smooth over and smear such edges. But if Phillip did not intentionally sgregate thigns as much as possible, it may still perform quite well.

O1 is very susceptable to banding, it is the alloy that I get the most "what are these funy lines in my steel" questions about. Many folks trying to speroidize or that drift a bit in their normalizing cycles end up with striking banding.
Click to expand...


Will alloy banding affect the hardness readings? Seems like if the steel is ductile (soft?) enough to bend easily, then it would read softer. Am I wrong? The as quenched hardness was 65 RC.
Anyway, these blades don't seem inclined to bend easily. In fact, I had a horrible time fixing the aforementioned warpage. I ended up softening the spine and tang with a torch and hammering them straight. The tang still is in the lower 50s.
I'll give these blades some serious testing before I sell them. What material do you recommend for test the strength of the edge? Maybe whittling osage orange? :)
 
If you are getting even results and did not go out of your way to segregate carbide into the banding, you should do all right. It may be a batch of O1 that had heavy alloying segregation, which would result in even martensite hardness, but areas of greater and lesser wear resistance due to alloying. Considering the fondness of rope and other abrasive fibrous materials as the "ultimate testing medium":rolleyes: most folks should be very happy with the blades. But for what it is worth industry does go out of its way to eliminate this effect as much as possible.

As I have said before, considering the wide array of things that folks think are great in the performance category of custom knives, just making something that will cut is a winner. ;) It is patently obvious that most knife users never push their blades far enough to notice the differences most of us fret over. My point here addresses the same concern I always have, that is not that this blade or that blade is inherently inferior, but too many folks try to hype anything different up as revolutionary and superior (I know you are not doing that) when it is only "different" and may even have some drawbacks, regardless of whether the drawbacks will ever be noticed in regular use.

J.D. Smith did a lot of this effect in his blades for a while, and I believe it was O1, but in conversations with him he always made it clear that it was another visual feature to utilize and he never made any claims of super steel or that it was anything that it wasn't. I feel the same way; it is very visually stunning and should perform quite in line with many other in-demand blades. So you should do fine, I just wanted to give you all the aspects of it.
 
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