Study on Crack Defects of Large-Sized 7A04 Aluminum Alloy Ingots
The 880 mm diameter 7A04 aluminum alloy ingot was prepared by electromagnetic casting method,and the formation causes and inhibition measures of the crack defects in this aluminum alloy ingot were investigated by industrial CT scanning,SEM & EDS and other inspection and analysis means,and the number and distribution of the tiny defects in the region near the defects were analyzed at the same time.The results showed that the essence of cracks in this ingot was the enrichment of Al2O3(oxide)and a small amount of Fe elements,and the location was close to the center of the ingot.It is observed that the number of micro defects decreased slightly with the increase of radius size and the largest percentage of the defects was more than 40μm.The analysis showed that the formation of micro defects was related to the formation of crack defects.Removal of inclusions and gaseous hydrogen from the alloy melt before casting,perfecting the process of degassing and slag removal are ways to avoid these defects.
国家科技期刊平台
NSTL
万方数据
