近年来,人们对大口径火炮身管锻件的兴趣日益集中在回火脆方面。低合金钢在325～575℃范围内缓冷或等温时,产生回火脆,因而使回火温度受到限制。采用快冷通常很容易减少脆性,但却会在锻件中,特别是在内膛上产生很高的残余拉应力。虽然可以采用在一定的温度下,以一定的速度冷却的方法去除应力,但这就使锻件再次处于回 In recent years, interest in large-caliber guns forgings has been increasingly focused on tempering. Low alloy steel in the 325 ~ 575 ℃ within the range of slow cooling or isothermal, resulting in temper brittleness, thus tempering temperature is limited. Fast cooling often reduces brittleness easily, but creates high residual tensile stresses in forgings, especially on the bore. Although the method can be used at a certain temperature to cool at a certain speed to remove stress, but this makes the forging again in the back