机床滑动导轨微织构多目标优化设计

Multi-Objective Optimization Design of Micro-Texture of Sliding Guideway in Machine Tool

为探索满足数控机床对其导轨高承载性、高精度、高精度保持性等方面要求的新途径,提出在滑动导轨表面制备椭圆开口偏置类抛物线微织构。选取矩形滑动滑块导轨副为研究原型,通过CFD方法对其在流体润滑状态下的承载压强、摩擦系数、温升及在乏油状态下的表面接触应力进行分析;基于响应面理论,通过CFD方法研究了微织构形状参数对导轨承载压强和摩擦系数的影响规律,并优化得到最优微织构形状参数;在此基础上,研究了微织构分布参数对导轨承载压强、摩擦系数、温升的影响规律,并优化得到最优微织构分布参数;最后,对最优特征参数微织构导轨的承载压强、摩擦系数、温升及乏油状态下的接触应力进行仿真分析,并将其结果与原型导轨相关性能进行对比。结果表明,该新型微织构可使导轨在润滑状态下的承压强提高15.15%,摩擦系数、温度及乏油状态下的接触应力分别降低26.43%、7.94%和8.09%。

To explore new ways to meet the requirements of high load-bearing,high-precision and high-precision retention of its guide rails by CNC machine tools,it is proposed to prepare an elliptical opening offset parabolic microtexture on the surface of the sliding guide rail.The rectangular sliding block guide rail pair is selected as the research prototype,and its bearing compression force,attrition modulus,exotherm and outside contact stress in the state of exhausted oil are analyzed by the CFD method.Based on the response surface theory,CFD is took on the effect of microtexture shape arguments on the bearing pressure and attrition coefficient of the guideway was researched,and the optimal micro-texture shape parameters were optimized.On this ground,the effect of the micro-texture distribution arguments on the bearing pressure and attrition modulus of the guideway was researched.The influence law of temperature rise and the optimal micro-texture distribution arguments was also researched.Finally,the load-bearing pressure,friction coefficient exotherm and contact stress in the state of spent oil of the optimal characteristic parameters of the micro-texture guide rail are simulated and analyzed.Comparing the results with the relative performance of the prototype guide rail,the results show that the new micro-texture can increase the pressure bearing strength of the guide rail in the lubricated state by 15.15%,and reduce the friction coefficient,temperature and contact stress in the depleted state by 26.43%,7.94%and 8.09%.