4 ms·
I don't know about his general claim, but a detail within his comment is right. Smaller grain size leading to stronger material -- this is a result of more gra
by CriticalCathed 7y ago
I don't know about his general claim, but a detail within his comment is right.
Smaller grain size leading to stronger material -- this is a result of more grain boundaries as the scale of the grain goes down. Hall-Petch strengthening.[0] A secondary effect is that with smaller grains oriented in random directions the metal is more resistant in general from stresses in all directions; whereas with larger grains you tend to get weakness in a particular direction (along the slip planes.)
This is common knowledge, at least it's basic material physics that I learned in college.
[0] https://en.wikipedia.org/wiki/Grain_boundary_strengthening https://en.wikipedia.org/wiki/Grain_boundary_strengthening
- kwk1 7y agoThe GP comment is claiming the opposite--that larger grain size results in a stronger material.
- elif 7y agoActually I said strong is too ambiguous of a term to use. For instance, do you want it "strong" enough to not bend under x force at y temperature, or do you want it "strong" enough to bend rather than shear at z force? It is more practical to discuss the hardness and ductility at specific temperatures, as well as its ability to keep its carbon content under those temperature conditions.