Morphology, fractographic analysis and their relationships with the mechanical properties of high temperature aged AISI 316 stainless steel.

摘要

The thermal-mechanical behaviours, microstructure morphology, fractograph, and their relationships for high temperature aged AISI 316 stainless steel were studied.;The fractograph of separated grain boundary facets for tensil tests and Charpy fracture facets are directly related to the microstructure of grain boundary. However, as long as chromium carbide forms a continuous network at the grain boundary, it may be the continuity, not the density of chromium rich carbide at the grain boundary that deteriorates the mechanical properties, such as ductility (percentage elongation), and fracture toughness (Charpy energy).;The chromium carbide precipitation for AISI 316 stainless steel was significantly affected by the pre-plastic deformation and subsequent aging treatment.;Extensive secondary intergranular cracks and ductile dimples were found on the fracture surface for aged AISI 316 stainless steel under tensile loading at ;The results show that AISI 316 stainless steel aged at 650