Alloy banding

[Eli Jensen]

Well, here I am again, feeling like a total noob. I think I've got an alloy banding problem. I've got a bajillion questions but pretty much three main ones.

1) Could it be the supplier? Jantz, not Aldo

2) What causes it?

3) How do I get rid of it?!?!!?!?!?!!?!?!?!?

[WynnKnives]

Once again I preface a post in "I'm not a professional" BUT I have taken a metallurgy class and I will try to see if it says anything about it in the giant text book I have.

As I understand it this is something that happens at the mill, and there is nothing you can do about it. Because what it is, is the different alloys are in higher concentrations in different areas. They obviously do not do this intentionally nor do they want to do this. But this is what happens when man makes things, mistake happen.

I know there are some out there that like to try and bring it out. Also I understand that after a good HT you still get the same amount of martensite, but the alloys are just allocated differently. I had a batch of ATS-34 that had very noticeable banding, actually I have a blade of it in the shop that I'm thinking about lightly etching because it is very prominent. Then testing it and seeing what happens.

For me it falls into the category of being different, some people love it, some hate it and think it should die and are disgusted by it. For me I figure really how is it much different the intentionally pattern welded steel? I dunno, you decide.

[Ray Rogers]

Now I see what you were talking about last night. If Wynn is right about the cause, and if those spots are banding, then there isn't anything you can do to remove them short of remelting the steel. If you put a sandblasted finish on that blade it should help conceal the spots and make the blade a uniform light grey color (no hamon). Or, some type of coated finish like nitride would conceal them....

[Fulmaduro]

How old is your etchant? Actually maybe your etchant is worn out or has something foreign in it.

One of my blades looked way worse than that and my fellow ABS buddy said his etchant obviously needed replacement. Haven't etched at his house since. But worth a try.

Tony Z

[Eli Jensen]

Etchant is brand new. I did get the steel from Janzt and I was worried about how good their steel is. Going to try a few things to see if its me or the steel. Otherwise, I think I'll throw this into the HT KITH, in addition to my 'real' entry

[WynnKnives]

The more I look at it the less it looks like alloy banding, if it is, it's very uniform. I know the banding on my ATS-34 looks like a bunch of V's. and most of the banding I've seen is similar to this... (not my picture), it's normally very random and not uniform. And like I said before, if it is banding it's the mills fault, personally I wouldn't hold this against Jantz they don't have any control over it. And as far as the mill goes I suppose when you have thousands of tons of steel this is going to happen every once in awhile.

[GHEzell]

Try a normalizing cycle at 1600F or a bit hotter with a five minute soak.
Then a few lower temp cycles at 1450F or so.
Then heat treat.

This advice was given by Ric Furrer as a way to remove alloy banding in simple steels. Out of curiosity what was your normalizing procedure?

[fuzzy]

Don't know about 1084 but I do have a 1075 blade that shows this same patern. I wondered if it was in the clay cote and sanding patern before heat treat? Didn't show up until it was etched. I'm with Ray on lose the hamon and a 600 grit finish and it disapears.