悬臂铝合金型材伪分流挤压模具结构设计及其强度分析

Fake Porthole Extrusion Die Structure Design and Strength Analysis for Cantilever Aluminum Alloy Profiles

铝型材挤压工艺和模具设计不仅需要保障挤出型材质量,还要保障模具强度和寿命,但对于大而长的悬臂铝合金型材,常规平模或导流模结构设计往往导致模具悬臂部位损坏,即使将模具相应部位加厚,也很难达到提高模具强度的要求。以某大悬臂铝型材为例,研究伪分流模具结构设计方法及长悬臂梁分解技术,对比分析常规模具设计与伪分流模具设计对型材挤压速度分布、温度分布、材料粒子运动轨迹等的影响规律,研究不同结构的模具强度。研究表明,采用伪分流模具不仅能够大幅度降低模具应力,而且通过材料流动优化可获得良好的材料流动规律和型材质量。总结给出伪分流结构的设计原则。

The objective of aluminum alloy profile extrusion process and die design is to ensure the profile quality and die strength. But for large and long cantilever aluminum alloy profiles, the conventional flat die and diversion die design usually cause the damage or failure of die in the cantilever area. Even through increasing the thickness of die in these areas, it is still difficult to ensure the die strength or life-time. With a large cantilever aluminum alloy profile as an example, the fake porthole die design method and cantilever decomposition technique are studied. The material flow velocity, temperature, particle track and the die strength of the two different die design methods are studied and compared. Especially, the die strength and stress distribution are researched. The results indicate that the fake porthole die design method is a useful die design method for large and long cantilever aluminum alloy profiles. It can decrease the die stress significantly and ensure the die strength. The sound material flow and profile quality are also obtained by optimizing the fake porthole die structure. The design rules for fake porthole die structure and the material flow based die shape optimization method are given.