Crack behavior of roll material for hot rolling and stress and strain analysis by steel ball indentation test

摘要

In order to clarify the initiation of surface cracks,which become the starting point of spalling, steel ballindentation tests and stress-strain analysis by using the finiteelement method were carried out. From the results ofindentation tests, in the case of all roll material, crackpropagates through the carbide, which is in the roll material,and the crack initiation point is inside the contact circle. Fromthe analytical results by using the finite element method, theequivalent plastic strain of the crack initiation point in the steelball indentation test was the maximum. For that reason, it isconsidered that the crack generated from this position.