Industrial Need
Industry members continue to highlight the issues around conducting welding repairs on materials that are conventionally considered un-weldable. The associated cost of scraping parts is considerable from both a material and fabrication cost stand-point. The economic benefit gained by improved fabrication and repair procedures for both aero engines and industrial gas turbines is substantial, with savings to be made from repair of both high and intermediate pressure gas turbine blades made from nickel superalloys that could amount to several million pounds per set.
Objectives
- Develop a procedure combining a state of the art TIG welding system utilizing HF pulsing, with optimised forced cooling for repairing of nickel based super alloys
- Perform multi-stage trials to eliminate weld or post-weld heat treatment cracking of Mar-M247 weld build-ups
- Demonstrate repair procedure on example component and perform metallurgical analysis to demonstrate capability of repair
Project Outline
The proposed project supports one of AFWE’s key technology strands, related to the advancement of Tungsten Inert Gas (TIG) for repair of nickel superalloys. The initial aim is to establish the state-of-the-art in the repair of cast and/or single crystal materials, to drive the future direction of research. This knowledge will be used to develop potential solutions to the on-going problem of conducting weld repairs on difficult to weld materials such as Inconel 713 and Mar-M 247.
From a process and industry sector perspective, this relates to advancement of techniques and knowledge in the application of high quality (TIG/Plasma) arc welding processes, predominantly used in Aerospace applications.
The project will examine several variants of the TIG process – (high frequency) pulsed/AC TIG, and forced cooling – for weld repair of several alloys where cracking has been identified as an on-going problem.
Relevant Industry Sectors