Welding heat treated 4130
Welding heat treated 4130
(OP)
If I have two 1/4" thick 4130 plates that I've quenched from 1600F and tempered at 900F. I then take these two plates and stick weld them together using a 4130 rod. Is the resulting weld likely to be stronger or weaker then had the two pieces been annealed in the first place. If it's likely to be weaker is it due to a more or less random heat treat resulting from the weld or weld related stresses?
I am building a replacement drum for our battle robot, Redrum (www.teamentropy.com). We hope to use 1/4" thick plate rolled to a cylinder with 1/4" "teeth" sticking out radially. Our nemesis has similar construction but is unheat treated so I am tempted to add this extra step to give us an edge but I'm worried about replacing the teeth because they will come off in combat. One option I've considered is to locally heat treat the teeth with a torch after assembly or repair.
Thanks for the help you offer now or in the past,
-Seth





RE: Welding heat treated 4130
It is generally easier to weld annealed 4130 than a quenched and tempered 4130 -- you are less likely to crack the material along the HAZs. For your application, you would appear to be better off welding annealed material with the 4130 electrode and THEN heat treating the entire weldment -- you'll be giving up nothing in the area of the weld and you can tailor the temper cycle to suit your application.
Matt Nousak, P.E.
Senior Staff Engineer
Middough Associates Inc.
nousakmj@middough.com
RE: Welding heat treated 4130
Thank you,
Seth
RE: Welding heat treated 4130
RE: Welding heat treated 4130
There are any number of hardfacing filler metals out there, from tungsten carbides to chromium-molybdenum alloys, that would give you plenty of "bite". You could shape the profile of the hardfaced tooth by grindingj -- both originally and when performing repairs. That would seem to be less costly and easier to do up front, and also easier and cheaper during repairs. Just re-hardface the tooth stub. Some nickel-base filler metals might also do the job.
What welding processes are available to accomplish this work?
Matt Nousak, P.E.
Senior Staff Engineer
Middough Associates Inc.
nousakmj@middough.com