mechanical & microhardness properties of AISI 316L.

by kuldeep singh
(punjab, india)

SIR, i m doing my project on welding of ss 316L by tig. the joints obtained giving good mechanical properties on higher heat input i.e on 110 amp. as compare to 70 amp. current.

this is violating fundamentals.why is it so?

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kuldeep,

microhardness and mechanical properties of 316L are only part of the equation. what about carbide precipitation, grain growth, and maintaining corrosion resistance?

are you saying that microhardness has higher values with higher amperage? That does seem opposite of what is expected.

is this with 316L filler metal?

with pulse yag laser, which has much lower heat input and rapid solidification rates, microhardness values will almost always be greater than with tig welding.

so it doesnt make sense to me that your hardness values are higher with higher heat input.

you may be experiencing some hardening due to grain growth or carbide precipitation.

the only way to tell is with metallographic testing...section, polish, etch, and evaluate.


thanks for the question

Jody