Between 35 and 140 C/s the system at room temperature is a mixture of these two materials. The microstructure of martensite in austenite is shown in the micrograph. The black grains are the ...

Because of the low carbon content the martensite is relatively dispersed. In this tempering process, martensite precipitates Fe 3 C in an a-iron matrix and the micrographs show how the cementite phase ...