摘要:
Austempered ductile iron (ADI) is a difficult machining material with excellent comprehensive properties,and its high speed milling force has an important influence on surface roughness of the work-piece.Based on the combined mechanical properties,the multi-factor orthogonal regression experiment theory is applied to establish the relationship between the milling force and the surface roughness.In the experiment,the spindle speed,feed per tooth rate,cutting depth and cutting width are regarded as the multi factors,and the milling force and surface roughness are regarded as the dependent variables.With the least squares method,a model of the milling force and the surface roughness about the three components (Fx,Fy,Fz) is established,and the significance of the regression model and its coefficient analysis are conducted to verify the model and the influence level of three components(Fx,Fy,Fz) of the milling force.Finally,some verification experiments are designed to check the effectiveness of the experimental model.The experimental results show that the influence order of the three force components on the surface roughness is in turn:tangential force,axial force,radial force.The verification experiments prove the credibility and validity of the model,and it will provide an important theoretical support and technical guidance in high-speed milling process of ADI.%奥贝球铁(ADI)作为一种综合生能优异的难加工工程材料,其高速铣削下的铣削力对工件表面粗糙度Ra有重要影响.为研究其内在关系,基于多因素正交回归实验建立铣削力和表面粗糙度模型的理论,结合奥贝球铁的材料力学性能,采用以主轴转速、每齿进给量、切削深度、切削宽度等为多因素,高速铣削力和表面粗糙度为因变量的正交试验方法,并通过最小二乘法建立关于Fx、Fy、Fz这3个铣削分力的Ra模型;然后分别检验了回归模型和回归系数的显著性,分析了所建模型的可信度及Fx、Fy、Fz分别对ADI表面粗糙度的影响程度;最后设计了相关实验对所建模型进行验证.实验结果表明:高速铣削分力对表面粗糙度影响程度次序:切向力>轴向力>径向力;模型验证实验说明了所建模型的可信性和正确性,从而可为ADI材料高速铣削加工提供了重要的理论支持和技术指导.