滚柱滚压工艺参数对TC4钛合金表面粗糙度的影响

Influence of Roller Burnishing Process Parameters on the Surface Roughness of TC4 Titanium Alloy

钛合金是机械工程和航空航天等领域关键零部件的常用材料。在服役过程中,关键零部件除了受到稳定载荷作用外,还会受到交变载荷的作用,因而这些零部件表面极易造成裂纹的萌生,从而导致疲劳失效。为了满足关键零部件的表面性能和抗疲劳性能的要求,开展滚柱滚压TC4钛合金表面工艺性研究,选取压下量、滚压速度和行距3个工艺参数作为变量,以表面粗糙度为响应值,采用中心组合法进行试验设计,利用响应面法建立滚柱滚压表面粗糙度的回归预测方程。综合考虑加工效率和加工成本,选取表面粗糙度作为关键性能指标,对三项滚压工艺参数进行系统性优化。优化后的工艺参数为:滚压量为0.03 mm,行距为3 mm,进给速度为150 mm/min。在此参数组合下,滚压后表面粗糙度降低了67%。该试验结果可为钛合金滚柱滚压提供一定的实践借鉴。

Titanium alloy is a widely used material for key components in the fields of mechanical engineering and the aerospace industry.In addition to stable loads,they will also be subjected to alternating loads during service.Cracks are easy to initiate on the surface of these parts,which would lead to fatigue failure.In accordance with the surface performance and fatigue resistance requirements of key components,research is carried out on the surface technology of rolling TC4 titanium alloy.Burnishing depth,burnishing speed and feed rate are selected as variables,and surface roughness is taken as the response value.The central composite design approach is adopted for the test,and the response surface methodology is used to establish the regression prediction equation for roll surface roughness.The surface roughness is taken as the target,and the rolling process parameters have been optimized,taking into account the processing efficiency and processing cost comprehensively.The optimized process parameters are as follows:the burnishing depth is 0.03 mm,the feed is 0.03 mm,and the burnishing speed is 150 mm/min.Under this parameter combination,the burnished surface roughness is reduced by 67%.The test results can provide some practical reference for the roller burnishing of titanium alloy.