TA15钛合金电子束焊焊接接头力学性能

Mechanical properties of TA15 titanium alloy electron beam welded joint

摘要: 钛合金材料以及相关制造技术是实现飞机先进性的重要基础之一,电子束焊接是钛合金板材一种先进的焊接形式。对TA15钛合金板材电子束焊接试样进行了金相分析和静力试验、疲劳试验和扫描电镜(SEM)分析。结果表明,TA15板材电子束焊焊接接头的焊缝、热影响区和母材的微观组织差别明显;焊缝韧性降低,抗拉强度高于母材;热影响区尺寸较小,在1~2 mm左右,是焊接接头的薄弱部位;疲劳裂纹大多萌生于焊接热影响区区域,疲劳破坏试样断口的SEM分析表明,疲劳裂纹大多起源于焊接热影响区的气孔处。

Abstract: Titanium alloy and related manufacturing technique are one of the most important element of advanced plane manufacturing.Electron beam weld(EBW)is advanced welding method. Metallographic analysis, tension test, fatigue test and SEM analysis were conducted on the TA15 titanium alloy welded joint.Testing result indicated that weld metal, heat affected zone(HAZ)and base metal have different microstructures;weld metal has low toughness and high tensile strength.The width of HAZ is 1-2 mm.Fatigue testing result indicated that HAZ was the weak position.Fatigue crack mostly initiate at HAZ.SEM analysis of fatigue wrecked specimens indicate that most fatigue crack initiate from the gas pore of HAZ.