The Breakdown of Carbide Network in a H23 Tool Steel by Hot Axisymmetric Compression

Abstract

The effects of hot axisymmetric compression to break down the primary carbide network of the H23 tool steels were studied. This current study only focused on one strain rate of 0.01 s-1. The samples were deformed at 3 different temperatures (1000, 1050 and 1100 °C) with solutioning temperatures 1100 and 1250 °C, respectively. Afterwards, the samples were cooled by water quenching. The techniques used in this current study for investigation were the optical and electron microscopes and Vickers hardness test. The results show that hot axisymmetric compression had broken down the primary carbide network in the direction perpendicular to the compression axis and the carbides became finer. Although the highest hardness (274 HV) was achieved after solutioning at 1250 °C, followed by deformation at 1000 °C, however the microstructure analysis indicated that the optimum hot axisymmetric compression condition was solutioning at 1250 °C and deformation at 1000 °C.