摘要：To gain a deep insight into the hot drawing process of aluminum alloy sheet, simulations of cylindrical cup drawing at elevated temperatures were carried out with experimental validation. The influence of four important process parameters, namely,punch velocity, blank holder force(BHF), friction coefficient and initial forming temperature of blank on drawing characteristics(*** thickness and thickness deviation) was investigated with the help of design of experiments(DOE), analysis of variance(ANOVA) and analysis of mean(ANOM). Based on the results of ANOVA, it is shown that the blank holder force has the greatest influence on minimum thickness. The importance of punch velocity for thickness deviation is 44.35% followed by BHF of 24.88%,friction coefficient of 15.77% and initial forming temperature of blank of 14.995%. After determining the significance of each factor on forming characteristics, how the individual parameter affects characteristics was further analyzed by ANOM.

摘要：为研究超声振动辅助成形的内在机理,设计一套25kHz高频超声振动装置,配合试验机进行1050铝合金静态及振动辅助条件下的压缩试验。实验发现,振动有利于降低材料的流动抗力,同时有助于改善试样表面形貌;成形力的降幅与所施加超声振动的振幅成比例关系。结合有限元数值模拟,研究材料在超声振动辅助压缩条件下的变形特点,发现在振动阶段,试样与模具接触面之间的摩擦条件得以改善。此外,应力叠加和摩擦条件改善是振动阶段成形力降低的两个原因,但两者的降幅总和小于实验中测得的降幅,因此软化效应是成形力降低的另一原因。

摘要：薄壁铝合金管小弯曲半径数控弯曲是个多因素耦合、多模具约束下的复杂过程。提出以有限元模拟为基础,基于显著性的工艺参数优化方法,即采用析因因子设计分析工艺参数对成形质量,即最大壁厚减薄率和最大截面畸变变化率影响的显著性,获得影响显著的参数,即管与防皱模间间隙的最优值,并确定其他影响不显著的参数值,包括管与模具间的间隙和摩擦、芯棒伸出量和助推速度。结果应用于规格为d50mm×1mm×75mm和d70mm×1.5mm×105mm(管外径D0×管壁厚t0×弯曲半径R)的铝合金管弯曲,获得了合格的管件。