Electron beam welding of titanium aluminides

✍ Scribed by U. Reisgen; J. Holk; S. Olschok

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 414 KB
• Volume: 40
• Category: Article
• ISSN: 0933-5137
• DOI: 10.1002/mawe.200900513

✦ Synopsis

Abstract

This paper gives an account of research which has been carried out on electron‐beam welded specimens made of high‐Nb γ/α~2~‐titanium aluminides (in short: TiAl).

The high niobium content of this alloy (5–8 %) has a positive effect on the strength and the creep resistance and also on the oxidation resistance.

The standard welding parameters weld speed and beam current and also additional beam oscillation have been used for the determination of factors which will effect the solidification morphology and structural constitution since those, in return, exert influence on the high cracking susceptibility of the alloy. In order to reduce the critical cooling rate, preheating which has a positive effect on crack formation has, in addition, been applied.

In a direct comparison of both alloys, micrographs and electron beam micro‐analyses of the developing weld structure and of the HAZ the effects of the beam parameters on both alloys have been established.