来源：http://www.jnhjgs.cn 发布时间：2020-07-06 17:57:48 点击：
1、 Tempering after oil quenching is a typical heat treatment process for forging die steel.
2、 Quenching of steel is a heat treatment process in which the steel is heated to the critical temperature AC3 (hypoeutectoid steel) or AC1 (hypereutectoid steel), holding for a period of time to make it whole or partially austenitized, and then rapidly cooled to below MS (or isothermal near MS) at a cooling rate greater than the critical cooling rate for martensite (or bainite) transformation. Generally, the solution treatment of aluminum alloy, copper alloy, titanium alloy, tempered glass and other materials or the heat treatment process with rapid cooling process is called quenching.
3、 Tempering is a metal heat treatment process in which the quenched workpiece is reheated to an appropriate temperature lower than the lower critical temperature AC1 (the starting temperature of pearlite to austenite transformation during heating), and then cooled in air, water, oil and other media after holding for a period of time. Or the quenched alloy workpiece is heated to a proper temperature, held for a certain time, and then cooled slowly or rapidly. It is generally used to reduce or eliminate the internal stress in quenched steel parts, or reduce its hardness and strength to improve its ductility or toughness. After quenching, the workpiece should be tempered in time, and the required mechanical properties can be obtained through the combination of quenching and tempering.