A fu-bar of steel, need metallurgical help. Stacy? Someone??

[Overmountain]

Hey all... Have been back to my lurker self since the HT oven went tits up. Still keeping busy with the bottle openers and repair/cab work. But then I hit this little gem of a snag... I haven't seen this before and I can't tell what's going on.

Here is the problem...

As you can see, there is an issue here. This is a virgin bar of 1095, properly annealed, and freshly ground out to 120 grit. Pre-HT. I am seeing wavy lines that aren't palpable but run along side my grind grain. They appear to be ghosted into the steel. Then there are what appear to be slag inclusions or something here and there. Then there are the very noticeable and palpable worm trails throughout. I've never had a stock removal blank appear like this. This was ground dry and fresh on a fresh belt to show what I'm talking about. I assume this bar is good for throwing in the recycle bin and that's about it.

I had HT'd a blank from the same bar, but it had some hot work done prior to HT. It had a weird patterning after an etch and polish, but it wasn't detectable with a fingernail like this is. I don't have a pic of that.. I had chalked that up to going over temp doing a forge HT.

Maybe it is the new prescription for contacts I'm wearing now or something, but I've never seen my steel do anhthing like this before...

Thanks all. And MERRY CHRISTMAS!!!
I hope everyone has a warm and cozy family Christmas with lots of love and joy. And to my friends who celebrate other concurrent holidays, happy Chanukah, Kwanzaa etc.

Cheers! Designate a driver Y'all!

-Eric

 

[Rick Marchand]

You didn't mention your heat treat method. You said your oven is out of commission... did you eyeball it in a forge? What type of quench medium are you using?

 

[sunshadow]

Is that from Admiral? I got some 1095 from them before Aldo started selling that had horrible banding and segregation

-Page

 

[Overmountain]

You didn't mention your heat treat method. You said your oven is out of commission... did you eyeball it in a forge? What type of quench medium are you using?

This blank isn't HT'd yet. Still in annealed form. Straight from the manufacturer. No normalizing, nothing.

Is that from Admiral? I got some 1095 from them before Aldo started selling that had horrible banding and segregation

-Page

I believe it is from the end of 2012 and was an 1/8 x 2" bar that I think was from Jantz. Which I've had issues with before... But not this.

To my eye it doesn't look like typical alloy banding for some reason. It's like 'inclusions' in the steel. Hair like lines. In one section it literally looks like a hairball smashed flat... I've seen banding come up with a light etch but never anything this pronounced. Even though it was pre-HT and all I hadn't dug into the steel hard enough to get it all that hot. Not even any straw colored oxidation on the tip, etc.

I think just for 'gits and shiggles' I'm gonna finish it out and HT it.

Thanks for the input.

Merry Christmas again!!

 

[me2]

If it's a fix it or loose it type situation, you could try heating it up to about 1650 and soaking a minute or 2 and then air cooling. If it's carbide segregation, that should take care of it. If you're ovens out, do you have a forge to use? If you don't have a heat source, maybe a heat treater could do it for you as part of the process.

 

[Overmountain]

If it's a fix it or loose it type situation, you could try heating it up to about 1650 and soaking a minute or 2 and then air cooling. If it's carbide segregation, that should take care of it. If you're ovens out, do you have a forge to use? If you don't have a heat source, maybe a heat treater could do it for you as part of the process.

I will probably try a soak, general normalizing etc... I've seen carbide segregation in spots, or look like the broken sheets of ice on a glacier field, or even run along unform bands; strata to strata. This, though, is meandering about and goes through the thickness of the steel (as far as I can tell from grinding a bit of a distal taper) without regards to the structure around it. I guess I need to get it a bit smoother and etch it to really bring out a pattern if there is any... I know that technique is used fairly frequently to view structures within the steel. It is clear that it is grinding at a different rate than the surrounding steel as a fingernail can definitely catch in it.

Mh HT oven should be back in service this week. I don't like to use the forge for anything I'm trying to control for obvious reasons. It's not a big deal in the end if the blade is ruined, it is just playing around stuff and not 'for' anyone in particular.

Thanks guys. Go enjoy your Christmas. I am about to go play Santa for a couple of hours and then act all rested when the kids get me up at 6am... lol.

Cheers!
-Eric

 

[Rick Marchand]

Me2 is right... get that baby up in the 1650F-1700F range to dissolve any unwanted structures, If they are still there, you know it is beyond repair.

Merry X-mas everyone!

 

[Matt Rochester]

I had some 440c do the same thing with the worm trails. They almost looked like water trails after washing your car. They are hard to see in a picture but they were there through all stages of grinding. You had to get the light right but were very noticeable when you did. I never could figure them out. I got some 1095 from jantz and haven't had any problem with it. I think it was just a bad batch.

 

[Overmountain]

Me2 is right... get that baby up in the 1650F-1700F range to dissolve any unwanted structures, If they are still there, you know it is beyond repair.

Merry X-mas everyone!

That's the plan anyway... My concern is that it is something insoluble, hence why it appears in the pattern that it does. I'm stymied by exactly what it could be. It doesn't act like typical carbides as it seems softer than the surrounding annealed steel. No grain apparent to it... But it is the last of that bar, and just a 'foolin around' kitchen blade. (If it had turned out it was going to be a 10" chef's blade for the wife...) Nothing lost either way so I will definitely try a soak and see where it goes.

I had some 440c do the same thing with the worm trails. They almost looked like water trails after washing your car. They are hard to see in a picture but they were there through all stages of grinding. You had to get the light right but were very noticeable when you did. I never could figure them out. I got some 1095 from jantz and haven't had any problem with it. I think it was just a bad batch.

I had some inconsistencies with Jantz 1095 and D-2 in the past. Nothing like this, but just some apparent chemsitry differences yielding differing results in the HT. Certainly not to bash them, and I still get stuff from them fairly regularly. Just not steel anymore.

Cheers and Merry Christmas. I'm playing with my son's new Nitro R/C car!! I think I bought it as much for me as I did him... lol.

-Eric

 

[Russ Andrews]

Looks like the tail end of a mill run where the steel was
allowed to cool a little too much....thus started to
come apart inside, instead of deforming properly
under the rolls.
Guys who forge...especially with a press, have seen this
happen when the dies pull the heat out of a thin/too cool
forging.

 

[Overmountain]

Looks like the tail end of a mill run where the steel was
allowed to cool a little too much....thus started to
come apart inside, instead of deforming properly
under the rolls.
Guys who forge...especially with a press, have seen this
happen when the dies pull the heat out of a thin/too cool
forging.

The only thing that gets me about that, is when I've had that happen personally it has had a grainular appearance and more defined corners... Not as hair-like... It could be cold forging I guess... But usually cold shunts and the like appear linear and stratified if that makes sense.

Ah, I'm gonna call it null and try a soak. Might as well... After playing with the RC car of course... lol.

Thanks for the input guys. Extra sets if eyes and craniums help.

-Eric

 

[Stacy E. Apelt - Bladesmith]

I'm with Rick and me2.

Heat that up to at least 1700F and hold it for at least five minutes. Air cool. Heat to 1450 and hold for five minutes...quench. Then do a sub critical anneal at 1250 for 10-15 minutes and air cool to below 900....quench. If after grinding it smooth and removing the scale/decarb it doesn't look better...chuck it or save it for blacksmithing and non-knife projects.