Effect of microstructure on mechanical properties and fracture of dispersion strengthened platinum

摘要

Two types of dispersion strengthened Pt with thesame weight fraction (0.5percent) of Y_2O_3 particles areanalyzed in the paper. But the technological parameters of theirpreparation by application of laboratory manufacture procedureare different. The first material (A) has worse strength and plasticproperties in the temperature interval from 20 to 600beg C. At thetemperature 600beg C their properties are similar to the propertiesof pure Pt metal. Second material (B) has very favourable strengthproperties up to the temperature of 700beg C. They are two-threetimes better than those of the material (A) and they also exceed thestrength parameters of dispersion strengthened Pt materials used atpresent. In this explained on the basis of microstructural andmicrofractografical analyses. Better properties of the material (B)consist in grain refining of Pt matrix, low porosity and its stability,higher effectiveness of dispersion strengthening, inthermomechanical effect and with it connected increase ofdislocation strengthening.