Affiliation:
1. Siemens Energy, Gasturbinenwerk Berlin, Werkstoffprüflabor , Huttenstraße 12, D-10548 Berlin Germany
Abstract
Abstract
Failure analysts are sometimes surprised to find well-known metallurgical failure mechanisms at work in completely unexpected places. This contribution is an eloquent example for just such an incidental convergence of well-known failure mechanism and fabrication process where it was not reported to have previously occurred. Liquid Metal Embrittlement (LME) was observed in Narrow Gap Welds (NGW) produced for Welding Procedure Qualification (WPQ). The embrittling liquid metal was copper in this case. It is believed to have originated from copper backing used for weld pool protection. It was recommended to replace copper backing with ceramic weld pool protection.
Subject
Metals and Alloys,Mechanics of Materials,Condensed Matter Physics,Electronic, Optical and Magnetic Materials
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