关键词: 轴头, 合金钢, 水淬, 可控冷却

Abstract: Cooling characteristics of water and principle of controlled cooling of water quenching were analyzed. The shaft end of 35CrMo alloy steel forklift was quenched and tempered by means of controlled water quenching cooling and traditional water quenching, and the microstructure and microcracks of the quenched and tempered shaft end were tested. The results show that the quenched and tempered shaft end by controlled cooling has a fine and uniform tempered sorbite microstructure with moderate hardness and no microcracks, which meets the technical requirements. While 1/3 of the shaft ends quenched and tempered by traditional cooling has cracks. It can be seen that by controlling the initial temperature of water, the mass ratio of water to workpiece and cooling time, the alloy steel shaft end with complex shape can be cooled controllably, thus satisfactory quenching effect can be obtained and clean heat treatment can be realized.

Key words: shaft end, alloy steel, water quenching, controllable cooling