Which one, 304 or 321, is more heat-resistant?
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It is said that 321 is more heat-resistant than 304, but why does GB150 specify a higher allowable stress for 304 compared to 321 at high temperatures?
Logically, it should be the same; a higher carbon content helps with strength at high temperatures. At 150 degrees, the high-temperature strength of the two types of steel is similar below 400 degrees, but there is a slight difference above that temperature
Stainless steel is resistant to corrosion; if high temperature resistance is a priority, then heat-resistant steel plates are the better choice
Reply to 3# Deng Hongjuan: Economic factors need to be taken into account; heat-resistant steel is expensive
The two materials have similar compositions and mechanical strength, as well as similar temperature resistance.
The weldability of 321 is better than that of 304; I’m not aware of anything else regarding this