Microobservation of stress induced martensitic transformation in CuAlNi single crystals

Abstract

Stress-induced martensitic phase transformation of CuAlNi single crystals is observed by use of an in situ optical observation apparatus. The results show that long before the transformation of the parent phase becomes macroscopically noticeable, interfaces arise. After the macroscopic phase transformation is completed, interfaces do not totally disappear. The macroscopic yield stress is the stress for the growth of the martensite in the transversal direction, this growth goes on only from one side of the acicular martensite. The number density of martensitic plates does not change with different temperatures.