2011 年 52 巻 8 号 p. 1623-1628
The distribution of micro/nano-indentation hardness and microstructures of deformed Hadfield high manganese steel have been investigated by means of micro/nano-indentation tests, and optical and electron microscopic observations. Indentation tests demonstrated that there exists a very non-uniform distribution of hardness, with a hardness variation of ∼30% in different grains and in different regions of the same grain. Microscopic observations indicated that the large non-uniformity of micro/nano-hardness is caused mainly by the underlying non-homogeneous substructures (twins, dislocations, etc.), which are closely associated with the non-uniform work hardening in the deformed Hadfield steel, while the effects of the austenite grain boundary and the grain orientation of the indentation plane are not significant.