This research study was undertaken to evaluate whether gas tungsten arc welding (GTAW) could be utilised to extend the limits of an existing repair scheme. The compressor impeller of the GTC 85-71 suffers from such severe sand erosion to the leading edges, that the damage exceeds the manufacturers specification. The impeller is manufactured from Ti-6Al-4V. The study entailed performing a series of welding trials and post-weld heat treatments. After metallographic examination of the weld microstructure, mechanical property assessments (i.e. tensile and fatigue tests) were undertaken. The results demonstrated that the welds after the 550 °C/8 hr post-weld heat treatment had equivalent properties to those of the parent metal. The stress distribution determined by finite element analysis showed the weld to be in an area of low stress. The results achieved herein and the stress analysis showed that the GTAW process is feasible for extending the repair limits for restoration of the leading edges of the compressor impeller.

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