the minimum requirement of chromium content in TP-304L is 17% will the corrosion resistant properties change when we are getting a result which is 0.2% less in chromium in the sample
Not necessarily. You can't base corrosion resistance on a single constituent. SS 316, for example, has a lower chromium content than 304, yet is broadly more corrosion resistant. You have to look at all the percentages to judge; even then, you may have to test.
The big question for me would be this: If the supplier can't control the Cr component, what else is wrong? Is this a quality source?
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