中文摘要：

钛合金在航空、航天等工业中有广泛的应用,其中TC1钛合金在变形温度为860℃,应变速率为7.5×10-4 s-1时,延伸率最大可达710%,具有良好的超塑性,通过超塑性气压成形工艺可成形形状较为复杂的零件。根据深型腔负角度钛合金法兰盘零件的特点,提出了超塑性气压成形工艺,并根据零件尺寸特征设计了弧形底面和平底两种的模具,同时,根据TC1拉伸力学特性建立了材料的高温本构关系,应用MARC有限元对其超塑成形过程进行了模拟。结果表明,弧形底面模具成形零件最薄处为1.2 mm,壁厚分布标准差为0.198 mm,变薄率为40%,在成形过程中最大应力约6.6 MPa;而平底模具成形的零件最薄处仅为0.82 mm,壁厚分布标准差为0.303 mm,变薄率高达59%,在成形过程中最大应力约7.8 MPa。因此弧形底面模具厚度分布较均匀,壁厚减薄较小,最大应力较小,降低了应力集中程度,是该类零件超塑成形工艺较为理想的模具。

英文摘要：

Superplastic forming process of TC1 parts with deep cavity and negative angle was studied.Two models,with arcuate bot-tom and flat bottom respectively,were designed according to the dimension features of the parts.The strain-stress law of TC1 alloy was constructed from the tension test.The finite element analysis(FEA) of the process was carried out using MSC Marc.Comparison was made between the two molds,the one with arcuate bottom and the one with flat bottom.For the former,the minimum thickness was 1.2 mm...