Thank you all for your thoughtful responses. Now the question is, can I use the same bars that have already been heat treated, or do I have to start with a fresh 410 cond. A. I know some grades cannot be heat treated multiple times, but I am told by the heat treater that 410 is capable of...
This procedure is for a SA479 gr 410 Cond. A bars - air tempered to meet ASME SA193 gr B6. (4" dia)
Ramp at 400F per hour to 1375+/- 25F
hold at 1375 +/- 25f fpr 4.5 hrs
Air cool to below 400F
We also tried Vacuum harden and air temper (4.75" dia)
Harden Cycle
pump down to 100 microns or lower...
Would like you to help me out with a question. We have 4" to 5" 410 bars we had heat treating to meet B6. These bars have failed multiple heat treatment to meet B6. I am told by the heat-treater you can re-heat 410 indefinetely without any issues, is this correct?
