My question is, if I heat treat 303 Stainless Steel, will it retain the 30-50% elongation, which is good, or its tendency to creep under load, which is bad, or both, which is still bad.  Plus, I don't know anything about the process of heat treating, so I couldn't give any details on temps or quenches or the like.  Any advice in that realm would be greatly appreciated.

Background information:
I have a 303 Stainless Steel block, 8" x 2" x 1.5" tall, being loaded from the top with 10 - 30 kips.  Strain gages are mounting to measure the shear and bending strains.  The 303 Stainless shows signs of creep and plastic deformation, so I'd like to use something harder, but still retain a good % elongation such that the output of the strain gages will still give a reasonable uE/lb resolution.  It seems that the max stress on the block is around 60ksi under max load, so the block was under-designed significantly.  303 Stainless has a UTS/Yield Strength of 75/30 ksi, 30-50% elongation.  

I can:
Use readily available AISI 4140 Heat Treated Steel, which should give me a UTS/Yield Strength around 125/100 ksi, 18% elongation.  This will corrode, which is probably not a problem, but is yet to be agreed upon.
Heat Treat the 303 Stainless to get the Yield around 100 ksi.
Heat Treat 13-4 Stainless, which my co-worker "heard" is stronger, but I haven't had a chance to look into it.

Thanks for the info.

Chad Schneider
raidoh@yahoo.com