38MnVS非调质钢活塞锻后控制冷却工艺

Controlled cooling process of 38MnVS non-quenched and tempered steel piston after forging

对38MnVS非调质钢活塞进行锻后冷却处理并探讨了不同冷却工艺对非调质钢活塞的影响规律。首先,分析了不同冷却速率对非调质钢活塞的组织性能和力学性能的影响,可知,在冷却速率为50~90℃·min^(-1)下,非调质钢析出珠光体及铁素体时各方面的性能最优。然后,利用分选装置对非调质钢活塞锻件进行预选,挑选出达到合格锻造温度的活塞,并在4种不同的冷却工艺下进行冷却处理。冷却过程中,锻件首先进入冷却速率为50~90℃·min^(-1)的第1冷却装置,冷却至740~760℃;之后通过输送单元使活塞进入冷却速率为30~50℃·min^(-1)的第2冷却装置,冷却至290~310℃。工艺验证结果表明,这一冷却系统能够很好地满足使用方对活塞合格率的要求,得到的活塞锻件的性能稳定、品质优良。

38 MnVS non-quenched and tempered steel piston was cooled after forged, and the influence laws of different cooling processes on non-quenched and tempered steel piston were discussed. First, the influences of different cooling rates on the microstructure and mechanical properties of the non-quenched and tempered steel piston were analyzed, and it was concluded that the 38 MnVS non-quenched and tempered steel had the best properties in all sides when pearlite and ferrite were precipitated at a cooling rate of 50-90 ℃·min^(-1). Secondly, the non-quenched and tempered steel piston forgings were pre-selected by a sorting device, and the pistons with qualified forging temperature were sorted out. Under four different cooling processes, the pistons were cooled. during the cooling process, the pistons were placed into the first cooling device with a cooling rate of 50-90 ℃·min^(-1) and cooled to 740-760 ℃. Then, through the conveying unit, the pistons were entered into the second cooling device with a cooling rate of 30-50 ℃·min^(-1)and cooled to 290-310 ℃. The process verification results show that the cooling system can meet the requirement of the qualification rate for pistons of users, and the piston forgings obtained have stable performances and good qualities.