6060铝合金铸锭羽毛状晶缺陷分析

Analysis on FeatheryCrystal Defects in 6060 Aluminum Alloy Ingot

对6060铝合金铸锭中的羽毛状晶缺陷进行宏观组织和微观组织观察及力学性能检测。结果表明,羽毛状晶缺陷明显降低制品的横向伸长率,其微观组织中枝晶分布方向基本一致,较正常组织中的枝晶形态更为平直,且枝晶分布更为不均匀。低倍组织由许多平行的细条组成,为择优取向的孪晶,呈扇形分布,尺寸较大,生长方向与热流平行。羽毛状晶缺陷试样中相更加粗大,周围有其他化合物存在,在羽毛状晶组织的基体中,也分布着许多细小化合物相。

The feather crystal defects in 6060 aluminum alloy ingot were observed and analyzed by macrostructure,microstructure and mechanical properties.The test results showed that the feather crystals defect significantly reduced the transverse elongation of the product,and the distribution direction of dendrites in the microstructure was basically consistent,which was more straight than that in the normal structure,and the dendrite distribution was more uneven.The macrostructure was composed of many parallel thin strips,which were twin with preferential orientation,fan-shaped and larger size,the growth direction was parallel to the heat flow.In addition,the phase in the feather crystal defect sample was coarser and there were other compounds around it.In the matrix of feather crystal structure,many small fine compound phases were also distributed.