Why duplex or super duplex stainless steels are welded with low heat input type

I currently use 17-7 PH stainless which is hardened to condition CH after forming. raw matl is .1.75"X .12" X .008". Its main usage after hardening is silicon wafer retainer where it's contantly cycled up and down to putin and remove wafer after 40-60 sec process at 400C temp. At this high temperature this part seemed to deform after a a couple of hundred wafer which is what it was designed for in the first place. THere is a proposal to go to a different material to increase lifeline of this part. My question is..... can 321 SST be a plugin replacement. I know this has a higher temp rating but how about its forming characteristics, will it have spring properties, and wont become brittle after prolonged exposure to 400C.

0 Answers Novellus,

Differentiate between ferrite percentage and ferrite number?

0 Answers

Define rivets.

0 Answers Essar,

The requirement for ASTM A217 Gr. WC9 castings for valves components like Body and Bonnet were Normalising at 920+/- 20 Deg. C and Tempring 780+/- 20 Deg. C The specification calls furnace shall be calibtated within +/-14 deg. C The Heat Chart shows minimum temperature for normalising 900 to 920 Deg. C, but maximum temperature 960-990 Deg. C Tempering 780+/-20 Deg. C is within limits and accepted. Casting having integral test bars, heat trated along with castings passed in chemical znalysis and mechanical properties. Since normalising maximum temperature is not meeting specification, where castings can be salvaged or renormalised and retempered to meet specification. Whether it will have affect on remechanical properties testing

0 Answers Leader Valves,

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