Origins of asymmetric stress-strain response in phase transformations

摘要: It has been determined that the transformation stress-strain behavior of CuZnAl and NiTi shape memory alloys is dependent on applied stress state. The uniaxial compressive necessary to macroscopically trigger approximately 34% (CuZnAl) 26% (NiTi) larger than required tensile stress. For three dimensional states, response either alloy system directions dominant principal stresses along with hydrostatic component state effects are dominated by favored growth nucleation more martensite plates in tension versus compression. effect different pressure levels between states volume change considered small.