Effects of Heat Treatment on Strength Wear Sintered Alloy Steels

摘要

This paper presents the results of experimental research on thermal treatment of alloyed sintered steels and much the development of Fe-3Mn-1Mo-1.5Cr-0.5B-0.45Graphite powder using mechanical alloying (MA). It was analyzed the influence of MA time on the morphology of the compound by electron microscopy SEM. The research has followed the study of the particle size powder mixtures influence obtained by mechanical alloying, compaction parameters and sintering process on the chemical and structural characteristics of the alloyed sintered steels. Thus there were compacted samples at 600, 700 and 800 MPa. The samples were heated using argon at a temperature of 1150°C using 60 minutes as a maintaining time. Cooling to the room temperature was achieved using a speed of about 30°C/minutes. With the resulting steels, we have made metallographic determinations using optic microscopy and determinations of the main mechanical properties. Heat treatment took place (heating at 960°C and cooling in the H_2O solution and 10% NaCl) in order to improve the properties of alloyed sintered steel hardness and strength. Specimens quenched and tempered have high wear coefficient compared with specimens as-sintered.