结晶压力对真空差压铸造铝合金二次枝晶间距的影响

摘要

The effect of crystallization pressure on the secondary dendrite arm spacing of vacuum counter-pressure casting ZL114A aluminum alloy was studied through testing and analyzing the secondary dendrite arm spacing (SDAS) subjected to different crystallization pressures. Meanwhile, the relationships among the secondary dendrite arm spacing of vacuum counter-pressure casting ZL114A aluminum alloy and crystallization pressure and wall thickness were established. The results indicate that the effect of crystallization pressure on the secondary dendrite arm spacing of vacuum counter-pressure casting aluminum alloy is obvious. For the samples with the same wall thickness, the secondary dendrite arm spacing of aluminum alloy decreases with the increase of crystallization pressure. Under the same crystallization pressure, the secondary dendrite arm spacing of aluminum alloy decreases with the decrease of wall thickness. When the crystallization pressure is less than 350 kPa, the effect of wall thickness on the secondary dendrite arm spacing is obvious, while when the crystallization pressure is more than 350 kPa, the effect of crystallization pressure on secondary dendrite arm spacing is obvious.%通过测试与分析不同结晶压力下真空差压铸造ZL114A铝合金的二次枝晶间距，研究结晶压力对真空差压铸造铝合金二次枝晶间距的影响；并建立真空差压铸造ZL114A铝合金二次枝晶间距与结晶压力和壁厚的关系。结果表明，结晶压力对真空差压铸造铝合金二次枝晶间距影响显著，对于相同壁厚的试样，随着结晶压力的增大，铝合金二次枝晶间距减小；在同一结晶压力下，随着壁厚的减小，铝合金二次枝晶间距减小；结晶压力小于350 kPa时，壁厚对二次枝晶间距影响较大；结晶压力大于350 kPa时，结晶压力对二次枝晶间距影响较大。