罐身用3104合金熔铸过程熔体质量评价与控制

Evaluation and Control of Melt Quality during Melting and Casting of 3104 Alloy for Can Body

以某电解铝企业罐身用3104合金熔铸过程熔体质量为研究对象,采用PoDFA(Porous Disc Filtration Apparatus)法开展离线测渣分析,重点考察了熔铸线上典型位置处(保温炉出口、在线除气后、深床过滤后)渣的种类及含量。结果表明,采用电解铝合金化方式生产3104铸锭,保温炉出口熔体渣含量偏高,为0.202 mm^(2)/kg,渣的种类以TiB_(2)颗粒和Spinel(尖晶石)为主。经在线除气后,渣含量降低,为0.129 mm^(2)/kg,但整体含量仍偏高,渣的种类仍以TiB_(2)颗粒和Spinel为主。经深床过滤后,渣的含量降至0.031 mm^(2)/kg,渣的种类主要为Spinel。通过适当降低保温炉内熔体温度、延长静置时间、深床过滤前增加板式粗过滤等熔体处理工艺的优化,实现了3104合金熔铸过程熔体质量的有效提升,从而显著降低了后续冲罐过程的断罐率。

Taking 3104 aluminum alloy for can body as object,offline inclusion analysis was carried out using PoDFA(Porous Disc Filtration Apparatus),focusing on the identification of type and content of inclusions at different locations of casting line.The results indicate that for 3104 ingots produced by electrolytic aluminum alloying,the inclusions at the exit of the holding furnace are mainly composed of TiB_(2)and spinel particles,and the content is high,which is 0.202 mm^(2)/kg.After online degassing,the content of TiB_(2)and spinel is decreased to 0.129 mm^(2)/kg,however,the overall content remains high with the same inclusion type.After deep-bed filtration,the inclusion is predominately spinel with content further decreased to 0.031 mm^(2)/kg.By properly reducing the temperature of the melt in the holding furnace,prolonging the holding time,and adding CFF before deep-bed filtration,the melt quality of 3104 alloy is effectively enhanced,significantly reducing the rate of broken can during the subsequent punching process.