Dissimilar material joining of 6008 aluminum alloy to H220 YD galvanized high strength steel was performed by resistance spot welding with especial electrodes that were a flat tip electrode against the steel surface a...Dissimilar material joining of 6008 aluminum alloy to H220 YD galvanized high strength steel was performed by resistance spot welding with especial electrodes that were a flat tip electrode against the steel surface and a domed tip electrode upon the aluminum alloy surface. An intermetallic compound layer composed of Fe2Al5 and FeAl3 was formed at the steel/ aluminum interface in the welded joint. The thickness of the intermetallic compound layer increased with increasing welding current and welding time, and the maximum thickness being 7. 0 μm was obtained at 25 kA and 300 ms. The weld nugget diameter and tensile shear load of the welded joint had increased tendencies first with increasing welding current （ 18 -22 kA） and welding time （ 50 - 300 ms）, then changed little with further increasing welding current （ 22 - 25 kA） and welding time （300 -400 ms）. The maximum tensile shear load reached 5.4 kN at 22 kA and 300 ms. The welded joint fractured through brittle intermetallic compound layer and aluminum alloy nugget.展开更多
以新型双相高强钢为研究对象,采用不同的工艺参数进行正交试验,并对点焊接头进行拉伸测试,分析各因素对电阻点焊质量的影响;然后对点焊接头金相组织进行观察,分析新型双相高强钢点焊接头的失效模式和接头金相组织特征。结果表明,点焊接...以新型双相高强钢为研究对象,采用不同的工艺参数进行正交试验,并对点焊接头进行拉伸测试,分析各因素对电阻点焊质量的影响;然后对点焊接头金相组织进行观察,分析新型双相高强钢点焊接头的失效模式和接头金相组织特征。结果表明,点焊接头抗剪载荷的最优工艺参数为:焊接电流8 k A,焊接时间15 cyc,电极力2k N,此时点焊接头的最大剪切力达到最大值。优质焊点在拉剪试验中最先从熔核边界附近开裂,随后延伸至母材部分,直至点焊接头全部断开。展开更多
文摘Dissimilar material joining of 6008 aluminum alloy to H220 YD galvanized high strength steel was performed by resistance spot welding with especial electrodes that were a flat tip electrode against the steel surface and a domed tip electrode upon the aluminum alloy surface. An intermetallic compound layer composed of Fe2Al5 and FeAl3 was formed at the steel/ aluminum interface in the welded joint. The thickness of the intermetallic compound layer increased with increasing welding current and welding time, and the maximum thickness being 7. 0 μm was obtained at 25 kA and 300 ms. The weld nugget diameter and tensile shear load of the welded joint had increased tendencies first with increasing welding current （ 18 -22 kA） and welding time （ 50 - 300 ms）, then changed little with further increasing welding current （ 22 - 25 kA） and welding time （300 -400 ms）. The maximum tensile shear load reached 5.4 kN at 22 kA and 300 ms. The welded joint fractured through brittle intermetallic compound layer and aluminum alloy nugget.
文摘以新型双相高强钢为研究对象,采用不同的工艺参数进行正交试验,并对点焊接头进行拉伸测试,分析各因素对电阻点焊质量的影响;然后对点焊接头金相组织进行观察,分析新型双相高强钢点焊接头的失效模式和接头金相组织特征。结果表明,点焊接头抗剪载荷的最优工艺参数为:焊接电流8 k A,焊接时间15 cyc,电极力2k N,此时点焊接头的最大剪切力达到最大值。优质焊点在拉剪试验中最先从熔核边界附近开裂,随后延伸至母材部分,直至点焊接头全部断开。
