Kardall Posted July 27, 2017 Share Posted July 27, 2017 Hello everyone, been a while! I said a while ago that my friend had some metal to give me from work, and boy did he deliver! I got around 20lbs of High-Manganese proprietary metal from a refinery. They are cutoffs from the big pipes that they use. Because it is proprietary metal, the only thing he could tell me about it is that it is High-Manganese because he has to use a respirator full face mask to cut it with the cutting tools hehe. So one of the ribbon like pieces he gave me is pretty small, like 1/8" thickness and I was going to try to smooth it out, thin out the edge and see what kind of an edge it can hold. If it is good enough I might consider welding it into the edge of a blade, and use normal steel as the backer in the future if it is good enough. So my question is, I read here and many sources that warm peanut oil is a good 'go-to' method of hardening it before tempering it again, and I am going to try that, but is there any special secret that anyone has ever used when dealing with something like this. I can put pictures of it if you wish. As a side-note about the metal, i have probably 6-8 pieces that are around 2cm x 2cm x 15cm long (they are tapered from the angle cut on the pipe already so that's a lot less work I will have to do on the edges). But he also gave me two chunks of it from where they cut the pipe to put valves in. They are around 33cm x 20cm x 2cm in size, and I have to figure out a way to cut it without a plasma cutter HAHAHA. So that should be good once I figure out exactly what I am working with. Any comments / suggestions on an order of operation with this stuff? Quote Link to comment Share on other sites More sharing options...
Smoggy Posted July 27, 2017 Share Posted July 27, 2017 Think I'd try a few different quenchants to find out what I prefer. If it's high Mn then would it stand out well in a pattern weld? Quote Link to comment Share on other sites More sharing options...
JHCC Posted July 27, 2017 Share Posted July 27, 2017 If you have some pieces that you can sacrifice, try hardening in different quenchants (oil, water, brine) to see if it will harden enough to skate a file, and then do a break test: heat one end (in the forge or with a torch) until you have the full spectrum of temper colors running down the length, quench again, and then put each successive color over the edge of the anvil and tap sharply with a hammer (WEAR EYE PROTECTION!!!) to see where you get the right balance between hardness and toughness. Make a note of that temper color, and aim for that with your subsequent heat treatment. Quote Link to comment Share on other sites More sharing options...
Steve Sells Posted July 27, 2017 Share Posted July 27, 2017 I am sorry if what I already covered in the pinned post about hardening unknown steels isnt helping Quote Link to comment Share on other sites More sharing options...
Latticino Posted July 27, 2017 Share Posted July 27, 2017 Personally I would be just as concerned about how much grinding you will have to do to the mystery metal after forge welding it into a billet as a blade edge. Do you have a full face respirator to use that will work with a beard? Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 27, 2017 Share Posted July 27, 2017 As a bearded guy I prefer a positive pressure respirator as it doesn't have to be glued to the face to work! Quote Link to comment Share on other sites More sharing options...
Kardall Posted July 27, 2017 Author Share Posted July 27, 2017 Well I got out and spent a 40 minutes on a small section, just to see what happens. It is fairly strong stuff, and I think it has an odd heat tolerance or I hit it too hard. It got no thinner than 1/4" and started to split down the middle. could just be a weak part from when it was cut off. I will have to try some of the bigger pieces to see if i have any luck. Pictures incoming. Notes: It doesn't cut hair, but cuts boxes fine. Could be a box cutter maybe as it is lol. I will definitely try a bunch of heat treat options if I can scrounge up the different types of oil and such. I got all my life to do this so I took the more solid side of the split side, ground it down a little more after forging it to the point where I thought if I hit it anymore I would just make it worse. it's about 1/8" at the thickest part now. I just did water from an orange / bright red color at that tip part. It's all I have for tools/sandpaper right now, so I am not expecting a master blade edge HAHAHA Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 27, 2017 Share Posted July 27, 2017 looks overheated; how deep is your fire? So you have at least 4" of charcoal under the workpiece, (real charcoal not briquettes!) Quote Link to comment Share on other sites More sharing options...
Kardall Posted July 27, 2017 Author Share Posted July 27, 2017 Ya my forge is too shallow to be working with anything too big. I am running low on charcoal as it is, gotta get some more. But no, I have maybe 2" below it at the most. I had almost no air going into it just because I didn't want it to get too hot too fast. Probably still not enough, need more insulation between the fire and the metal I guess. I really have to consider making a new forge with those pyramidy shaped pits. :/ My forge is basically a 40 yr. old lawnmower turned upside down. Quote Link to comment Share on other sites More sharing options...
ThomasPowers Posted July 27, 2017 Share Posted July 27, 2017 too much O2 helps make thing steel "crunchy" as well. Some alloys have very narrow forging temperature ranges. Quote Link to comment Share on other sites More sharing options...
Kardall Posted July 27, 2017 Author Share Posted July 27, 2017 Hmm okay. I will take mental note for the next piece I try. Maybe next week, gotta get some Coal from the guy I got some last year. Two 5 gallon pails lasted me about 10-12 forgings of small stuff in a year. So I should be able to get by with another two pails for maybe half a year or more Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 27, 2017 Share Posted July 27, 2017 Yeah, that looks like a high manganese alloy alright. From the days of taking hard facing classes comes the warning that manganese alloy steels have a strict time and temperature limit. It's kind of funny stuff, more than a small % and the steel will fail if kept too hot too long and you can vary either to the same effect. Too hot for a short time and it breaks or not so hot for longer and it breaks. There's a threshold temp according to % but exceed it's limit and it breaks. I was more interested in hard facing drill bits and drill steels so manganese wasn't an issue, it was however a big part of the class. Lots of rock crushing equipment is high manganese and requires hard facing regularly. Some of the methods to control heat sinking into the base steel were pretty impressive. Huge crusher drums in water baths with barely a couple inches exposed to weld. The beads were run over amped and fast Fast FAST. Long skinny beads in multiple passes, run, skip a space run another and go back. Never run next to or touching the previous one. Anyway, Exceed manganese steel's time/temp limit and it breaks, seconds, sometimes hours even days later. Looks like your pics. Bummer but it happens when you're using salvaged stock, sometimes you're the pigeon sometimes you're the statue. Be careful grinding, too much is BAD for you especially if you breath it. Same for the smoke welding. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
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