1420铝锂合金典型构件超塑成形研究

摘要

Box-like structures of 1420 Al-Li alloy are prepared by superplastic forming. Influence of temperature on superplasticity of 1420 Al-Li alloy, wall thicknesses of box-like structures and fracture mechanism are investigated by means of finite element simulating and microstructure observation. The results show that wall thicknesses of box-like structures can be forecasted well by using finite element simulating method and the super-plasticity of 1420 Al-Li alloy is good at 520℃ and increase of deforming of material during superplastic forming induces join and polymerization of cavities in the material that results in fracture of 1420 Al-Li alloy.%采用超塑成形工艺制备了1420铝锂合金盒形结构试验件.通过有限元模拟及微观组织观察,分析了温度对1420铝锂合金超塑性的影响,超塑成形后试验件的壁厚分布及材料的超塑成形断裂机制.结果表明:有限元模拟能够很好地预测超塑成形后试验件的壁厚分布;当成形温度为520℃时,1420铝锂合金表现出良好的超塑性变形能力;在超塑成形过程中,随着变形量的增加,材料内部空洞的交连和聚合是导致1420铝锂合金最终破坏的主要机制.