(1. 中南大學(xué) 材料科學(xué)與工程學(xué)院, 長(zhǎng)沙 410083;
2. 航天材料及工藝研究所, 北京100076;
3. 東北輕合金有限責(zé)任公司, 哈爾濱 150060)
摘 要: 分別采用Al-Mg-Zr和Al-Mg-Zr-Sc合金焊絲為填充材料， 對(duì)2 mm厚的Al-Mg-Sc合金薄板進(jìn)行惰性氣體保護(hù)焊接， 然后對(duì)兩種焊接接頭的顯微組織和力學(xué)性能進(jìn)行對(duì)比研究。 結(jié)果表明： 采用兩種焊絲焊接的Al-Mg-Sc合金薄板的焊接接頭強(qiáng)度系數(shù)均大于0.9。 但采用Al-Mg-Zr-Sc合金焊絲為填充材料時(shí)， 焊縫晶粒組織明顯細(xì)化， 熔合區(qū)形成的細(xì)小等軸晶層提高了基材與焊縫填充材料的結(jié)合力， 焊接接頭的屈服強(qiáng)度比采用Al-Mg-Zr合金焊絲為填充材料時(shí)提高了100 MPa， 顯著提高了Al-Mg-Sc合金焊接構(gòu)件的許用強(qiáng)度, 因此焊接Al-Mg-Sc板材更宜采用Al-Mg-Sc-Zr焊絲。
關(guān)鍵字: 鋁鎂鈧合金焊接; 焊絲; 熔合區(qū); 焊接接頭； 組織與性能
（ 1. School of Materials Science and Engineering, Central South University, Changsha 410083, China;
2. Institute of Spaceflight Material and Technology, Beijing 100076, China;
3. Northeast Light Alloy Co. Ltd., Harbin 150060, China）
Abstract: The Al-Mg-Sc alloy sheets with 2 mm thickness were welded by manual labor inert-gas arc welding method, the mechanical properties and microstructures of Al-Mg-Sc alloy weld joints filled with Al-Mg-Zr or Al-Mg-Zr-Sc welding wires were studied comparatively. When the Al-Mg-Zr-Sc welding wire was used as filling material, the grains of welding seam were refined obviously, and the weld joint was greatly strengthened by forming of fine equiaxial grains layer in fusion zone. The results show that, the coefficients of welded joints are both greater than 0.9, but the yield strength of weld joint filled with Al-Mg-Zr-Sc welding wire is greater 100 MPa than that of filled with Al-Mg-Zr welding wire. It indicates that the Al-Mg-Zr-Sc welding wire is the best alteration of filling materials to weld of Al-Mg-Sc alloy.
Key words: weld of Al-Mg-Sc alloy; weld wire; fusion zone; weld joint; microstructure and properties
