焊缝合金化对稀土铝锂合金焊缝组织及韧性的影响

Effect of Weld Alloying on the Microstructre and Toughess of Weld of Al-Li Alloy Containing Rare-earth Element

通过焊缝合金化手段，探讨了合金元素锆和铈对不同含铈量的２０９０铝锂合金焊缝组织及断裂韧性的影响机制，并对焊后人工时效处理的影响进行了分析讨论。结果表明，采用所研制的新型焊丝焊接２０９０Ｃｅ铝锂合金，其焊缝组织明显细化．焊缝金属的裂纹扩展阻力显著增加．而焊后热处理将导致焊缝断裂韧性下降．

An invcstigation was carried out to detewnine the effect of zirconium and cerium on the microstructure and fracture toughness of welds of 2090 Al-Li alloys containing different contents of cerium by means of weld alloying.The influcnce of postweld artificial ageing was also discussed.The results indicate that the weld microstructure can be evi- dentiy refined and the resistanee to crack propagation of weld metal is markedly irnproved if the filler alloy presented in the paper is used to weld 2090Cc Al-Li alloys.The postweld heat treatment will, however,lead to a reduction of the fracturc toughness of the welds.