摘要
以正反向超塑成形厚度均匀的TC4钛合金深筒形件为背景(厚度精度要求1.6mm±0.2mm),设计了多种预成形模形状,采用MSC.MARC有限元模拟研究了不同形状的预成形模对深筒形件侧壁厚度分布的影响,并分析了预成形模和终成形模的表面摩擦系数分别对成形件壁厚分布的影响,提出了模具型面变摩擦控制厚度分布的方法。结果表明:预成形模对压边部分环形带区域和筒形件底部区域的局部预减薄,对最终侧壁的厚度分布有非常大的改善。同时,合理地增大预成形模的表面摩擦能显著增加预成形的局部减薄作用,对于提高工件最终壁厚分布均匀性有利。减小终成形模的摩擦,可以使板料整体变形均匀化,壁厚分布趋于均匀。根据有限元分析结果,对模具表面进行处理,并通过正反向超塑成形实验制得TC4钛合金深筒形件,其厚度分布满足1.6mm±0.2mm。
Based on the direct-reverse superplastic forming TC4 deep cylinder with uniform thickness （thickness accuracy： 1.6mm±0.2mm ）, different shapes of preforming-die were designed and the in- fluence of the shape on the thickness distribution of cylinder was investigated using MSC. MARC. And also the influence on final thickness distribution of surface friction of preforming die and forming die was analyzed. The results show that the thinning of the blank near the periphery and the bottom of deep cylinder benefits to the uniform thickness of the side wall. And higher friction coefficient of preforming die can efficiently reduce the thickness of the regions which need to be thinned, results in a more uniform final thickness distribution along the component. Lower friction coefficient of forming die can make the sheet tend to integral formation, also results in uniform thickness distribution. According to the results of the FEM, the surface of performing die and forming die was treated and the aerospace TC4 deep cylinder was fabricated successfully by direct-reverse superplastic forming, the thickness of the cylinder meet the need of 1.6mm±0.2mm.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2009年第6期51-55,共5页
Journal of Materials Engineering
关键词
预成形模具设计
TC4钛合金
正反向超塑成形
厚度分布
摩擦
FEM
preforming die design
TC4 titanium
direct reverse superplastic forming
thickness distribution
friction
FEM
