表面处理对半封闭空心活塞杆热力学性能的影响

Influence of Surface Treatment on Thermodynamic Performance of Semi-closed Hollow Piston Rods

采用多弧离子镀技术在半封闭空心活塞杆表面沉积硬质涂层,通过有限元分析软件ANSYS的Fluent模块研究镀膜过程中各种工艺参数及传热方式等对活塞杆基体温度的影响.结果表明:极间距为50 mm和100mm时,活塞杆表面的温度相近,极间距为50 mm时活塞杆温度分布梯度较大;极间距为100 mm时活塞杆温度分布均匀;极间距为120 mm时活塞杆温度比前两者高,温度分布较均匀;极间距较小时,因温度分布不均而可能出现工件表面局部热量过大的现象,从而影响镀膜质量;极间距过大时,工件温度过高,可能产生大量的热应力从而影响膜基结合力,甚至使活塞杆受到损害.

The effect of various process parameters and heat transfer method on the temperature of the piston rod is studied by the multi-arc ion plating technique to deposit the hard coating on the surface of the semi-closed hollow piston rod. The heat transfer analysis is carried out by using the Fluent module in finite element analysis software ANSYS. The results show that the temperature of the piston rod is basically the same when the pole spacing is 50 mm and 100 mm,but the temperature distribution of the piston rod shows a great gradient when the pole spacing is 50 mm,and the temperature distribution of the piston rod is even when the pole spacing is 100 mm. When the pole spacing is 120 mm,the piston rod temperature is significantly higher than that of the former;the temperature distribution is more even. When the pole spacing is too small,due to uneven temperature distribution,the local heat of the workpiece surface might be too high,and thus the quality of coating will be affected. When the pole spacing is too large and the workpiece temperature is too high,a lot of thermal stress might be produced and thus the film combined force will be affected,and even the piston rod will be damaged.