The suitability of MVT and PVR tests for determining susceptibility to microcracking

摘要

In order to determine the hot cracking behaviour of high alloy austenitic steels, nickel-based, cupro-nickel and iron-nickel alloys, it is necessary to have test methods which clearly show the microcracking tendency and describe it in measurable units. This is possible using the modified varestraint transvarestraint (MVT) test and with the programmed deformation crack (PVR) test. Scanning electron microscope photographs of the crack surfaces provide clear differentiating features for solidification cracks, liquation cracks and cracks produced by decreased deformation.