铸造工艺对ZL114A铝合金铸件性能的影响

Effect of Casting Process on Properties of ZL114 AAluminum Alloy Castings

通过试验和数值模拟方式研究了重力铸造和低压铸造两种浇注方式对ZL114A铝合金平板铸件组织和性能的影响。结果表明,在熔炼工艺、热处理工艺相同的情况下,低压铸造铸件的力学性能均高于重力铸造铸件的性能,特别是伸长率明显;重力铸造条件下,铝液充型过程金属液易产生紊流,引起双层氧化膜裹着气泡卷入铸件使铸件产生缩松和气孔,其是试样断裂的裂纹源;重力铸造时由于缺乏有效补缩压力,铸件内部有明显缩松缺陷;低压铸造可以使金属液平稳充型,铸件中不会卷入双层氧化膜,而且铸件无明显缩松缺陷。

Effects of gravity filling method and low-pressure filling method on microstructure and proper- ties of ZL114A aluminum alloy plate castings were analyzed through experiment and numerical simula- tion. The results show that mechanical properties of the ZL114A alloy plates in low pressure casting are superior to those of ones in gravity casting at the same condition in the melting process and heat treat- ment process, especially the elongation rate. During gravity filling process, the liquid metal is easy to form turbulence, which leads to the shrinkage porosity and gas hole in the plates as a result of bifilm wrapped in bubble involved in plates, and it is responsible for crack fracture. During gravity casting process, due to the adequate effective feeding pressure, obvious porosity defect exists in the ZLl14A al- loy plates, while during low pressure filling process, the liquid metal is filled smoothly, and absence of bifilm will be involved in casting, so obvious defects in the casting is absent.