高温合金薄壁盘复杂零件加工变形控制方法

薄壁盘由于材料刚性较差等原因难以确保零件加工精度,容易引起变形,对此,提出了高温合金薄壁盘复杂零件加工变形控制方法。分析零件加工过程中产生的变形因素,包括夹装方式、刀具性能参数、工件自身因素、机床定位精度不够以及温度控制不佳等;确立所有工序历史误差源集合,生成误差传递矩阵,构建变形误差源诊断模型;针对不同误差源,提出针对性控制方法,通过最小二乘多项式拟合算法计算让刀误差,并对其补偿;通过有限元分析法建立工件几何模型,设立刚度控制函数,弥补工件自身缺陷;针对机床定位精度和温度分别设计控制函数,实现零件加工变形的综合控制。实验结果表明,所提方法明显减少了零件加工变形现象,保证了切削力平稳,提高了零件质量。

Machining Deformation Control Method of Superalloy Thin-walled Disk Complex Parts

The thin-walled disk is difficult to ensure the machining accuracy of parts due to poor material rigidity and is easy to cause deformation.Therefore , the machining deformation control method of complex parts of superalloy thin-walled disk is proposed.The deformation factors generated during the machining process are analyzed , including clamping method , tool performance parameters , workpiece self factors , insufficient machine positioning accuracy and poor temperature control , etc.The set of historical error sources of all processes is established , the error transfer matrix is generated , and the diagnostic model of deformation error sources is constructed.For different error sources , the proposed control method is tailored to calculate the tool letting error by least squares polynomial fitting algorithm and compensate for it. The workpiece geometry model is established by finite element analysis and the stiffness control function is set up to compensate for the defects of the workpiece itself.The control functions are designed separately for machine positioning accuracy and temperature to achieve comprehensive control of the machining deformation of the part.The experimental results show that the proposed method significantly reduces the part machining deformation , ensures the smooth cutting force and improves the part quality.