热障陶瓷涂层材料对柴油机活塞的影响

目的研究不同陶瓷材料对活塞温度和热应力的影响。方法以氧化镁-部分稳定氧化锆陶瓷(Mg-PSZ)和氧化钇-部分稳定氧化锆陶瓷(Y-PSZ)两种材料为研究对象,在硅铝合金活塞顶部分别喷涂Mg-PSZ和Y-PSZ等离子体,分析讨论了两种不同涂层材料对活塞温度场和热应力场的影响,对比分析了有无陶瓷涂层活塞温度场和热应力场的变化。结果和无涂层活塞相比,Mg-PSZ涂层活塞和Y-PSZ涂层活塞的表面温度明显升高,其表面最高温度分别升高了50.49%和34.81%,但是对应的基体最高温度却分别下降了28.49%和17.34%。同时还发现,Mg-PSZ涂层活塞和Y-PSZ涂层活塞具有相同的温度和热应力分布,并且其活塞基体和无涂层活塞也具有相同的温度和热应力分布。结论 Mg-PSZ涂层活塞和Y-PSZ涂层活塞都会导致活塞表面温度升高,应力增大,但是Y-PSZ对基体温度影响更大,Mg-PSZ对热应力影响更大。

Effects of Thermal Barrier Ceramic Coating Materials on Diesel Engine Piston

The work aims to study the effects of different ceramic materials on the piston temperature and thermal stress. With MgO-partially stabilized zirconia ceramic (Mg-PSZ) and yttria-partially stabilized zirconia ceramic (Y-PSZ) as objects of study, plasmas Mg-PSZ and Y-PSZ were sprayed on the top of AlSi alloy piston. The effects of two different coating materials on piston temperature and thermal stress field were studied, contrastive analysis was performed to change of piston temperature field and thermal stress field with ceramic coating or not. Compared with the uncoated piston, surface temperature of Mg-PSZ coating piston and Y-PSZ coating piston increased obviously by 50.49% and 34.81% respectively while corresponding maximum substrate temperature decreased by 28.49% and 17.34% respectively. Meanwhile, distribution of temperature and thermal stress on the Mg-PSZ coating piston was same as that of Y-PSZ coating piston, so was the distribution of piston substrate and uncoated piston. Both the Mg-PSZ coating piston and Y-PSZ coating piston can lead to the increase of the surface temperature and the stress. Y-PSZ has greater impact on substrate temperature while Mg-PSZ has greater impact on stress.