Effect of aging temperature on the microstructure and properties of alloyed high-manganese steel Einfluss der Alterungstemperatur auf das Gefüge und die Eigenschaften von legiertem hochmanganhaltigem Stahl

Abstract

This paper describes an aging treatment based on alloying the traditional high-carbon high-manganese steel to improve its initial wear resistance (wear resistance after water toughening treatment only). The changes in structure and mechanical properties of alloyed high-manganese steel after aging treatment at different temperatures were investigated using various experimental methods such as metallographic analysis, mechanical property testing, and fracture morphology observation.

The austenite grain boundary began to have the appearance of grain carbide at 550 °C; a large number of pearlites nucleated at the grain boundary and within grain at 600 °C, most phase transitions occur at 650 °C; and the pearlite and carbide began to revert to a soluble state at 700 °C, leaving only a small amount of pearlite in the austenite grain boundary. The hardness and yield strength of alloyed high-manganese steel increase and then decrease with the increasing aging temperature, and the high peaks appear in the range of 600 °C–650 °C; while the tensile strength and plasticity decrease and then slightly increase, with the highest and lowest peaks being approximately 550 °C and 650 °C, respectively.

At the aging temperature of 550 °C, the alloy high manganese steel has good comprehensive mechanical and deformation strengthening properties, with yield strength, tensile strength, elongation, and section shrinkage of 536 MPa, 1058 MPa, 51 % and 35 %, respectively. The changes in the properties of alloyed high-manganese steel are related to the pattern of structural changes that occur during the aging process.