Answer / akshita tyagi

magnetite is low grade iron oxide thai is it contains less amount of iron.
however nowadays taconite containing both magnetite and haematite is used in US. taconite contains more amount of magnetite and very less hametite

Answer / akshita tyagi

because magnetite is low grade that is it has less iron content.
however nowdays taconite is used in places where less amout of haematite is available. taconite consists of large amount of magnetite and very less amount of haematite.

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.

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