Effect of Melting Processing on Tensile Properties and Microstructure of New RAFM Steel Available to Purchase

All of the RAFM steels only safely used under 550°C, that is not enough for the next reactor. An new RAFM steel was melted by non-vacuum induction melting (VIM) and electro-slag remelting (ESR), followed by hot-forging and rolling into rods and plates. In this paper, we investigated the effect of thermal ageing treatment on tensile properties of the rods and plates. The microstructure was studied by OM (optics micrograph) and scanning electron microscopy (SEM). The results showed that by using the same heat treatment process, the tensile strength of the samples was 680MPa, the total elongation was 31%, which were better than the CLAM steel whose tensile strength and total elongation were 668MPa and 25% respectively. The difference between the transverse and the longitudinal properties was reduced markedly. So the ESR played an important part in improving the mechanical properties.