The effect of temperature and carbon content on the cavitation behavior of a 1.5 pct Cr-0.5 pct V steel

Constant strain rate tests at 10^-6 s^-1 have been carried out at 823 K and 923 K on a vacuum melted 1 1/2 pct Cr 1/2 pct V ferritic steel containing 3 different carbon contents. After straining to various elongation values specimens were unloaded, cooled and fractured at 77 K. This gave fracture surfaces consisting almost entirely of intergranular facets, enabling a quantitative study to be made of the different stages of cavity nucleation and growth. It was found that cavity growth rates were independent of carbon content but were higher at 923 K than at 823 K. Subsequent grain boundary sliding measurements, using a surface offset technique showed that sliding increased with increasing carbon content and that cavity nucleation occurred selectively at large grain boundary carbides. Formerly of the Department of Metallurgy, University of Manchester.