A380铝合金齿轮室压铸件开裂机制分析及改善

Analysis and Improvement of Cracking Mechanism of Die Casting A380 Aluminum Alloy Gear Chamber

对A380铝合金齿轮室失效件开裂部位显微组织、化学成分等进行分析,发现在产品两侧悬置区开裂部位存在缩松、缩孔、气孔、夹渣等铸造缺陷;利用有限元数值模拟软件分析产品在恶劣工况下的应力分布情况,显示在两侧悬置区应力集中,受力较大。认为铸造缺陷和应力集中的综合影响,是导致产品开裂失效的原因。通过改进浇注排气溢流系统、调整压铸工艺参数、优化产品结构设计等手段,产品开裂比例大幅度下降。

By analyzing the microstructure and chemical composition of the cracked part of the A380 aluminum alloy gear chamber,it was found that there were casting defects such as shrinkage porosity,shrinkage cavity,porosity and slag inclusion in the cracked part of the suspension area on both sides of the product.The finite element numerical simulation software is used to analyze the stress distribution of the product under bad working conditions,and it shows that the stress concentration in the two sides of the suspension area is large.It is considered that the combined effect of casting defect and stress concentration is the cause of cracking failure.By improving pouring exhaust overflow system,adjusting die-casting process parameters and optimizing product structure design,the cracking ratio of products has been greatly reduced.