高性能汽车发动机活塞材料与热处理工艺的研究

Study on High Performance Automotive Engine Piston Material and Heat Treatment Technology

为适应汽车发动机活塞越来越高的性能要求,从材料熔制和热处理工艺的改进入手,成功地研究开发了在共晶铝硅合金基础上加磷变质的过共晶型金相组织铝合金。指出发动机活塞的热处理宜采用T6或T7处理,对特种结构活塞可采用低温淬火+人工时效。若单纯采用时效处理,则必须在铸件出模后利用其余热采取相应的强冷措施,但应保证冷却条件,即工艺条件的稳定性。

To meet increasing performance requirements of automotive engine pistons,based on improvement of material melting and heat treatment process,an aluminium alloy with hypereutectic metallographic structure has been successfully researched and developed which is based on the eutect aluminium silicon alloy and modified with phosphor.It is noted the engine pistons are favourable to take T6 or T7 for heat treatment,as for pistons with special structure,the low temperature quenching plus artificial aging is suitable to use.If aging treatment is used solely,a forced cooling measure shall be adopted accordingly using the residual heat of castings after they are come out from dies,but the cooling condition,i.e. the stability of processing condition,must be guaranteed.