Thanks all! I'd like to investigate methods of post weld heat treating and stress releiving for 4140. Is wrapping the area with an insulated blanket for slow cooling sufficient? What types of blankets are available to use? I know unclesyd mentioned vermiculite insulation, any others?
I am trying to find out how much preheat to do when welding 2.50" thick 4140 bar to 1026 tube. I used Lincoln's calculator and got a preheat of 525 degrees F. I'm not very experienced with welding but this seems a bit high to me.
Here are the 4140 chemical properties I took into account...
