Laser cladding of the titanium alloy Ti6242 to restore damaged blades

Integrally bladed rotor disks are used to an increasing extent in low-pressure compressors (LPC) and highpressure compressors (HPC) of aero engines. These bladed disks are referred to as blisks. One of the objectives pursued under the EU sponsored AWFORS project is to test laser cladding for its suitability to restore damaged blades of titanium blisks. This paper describes details of the laser cladding process to manufacture conventional and blade-like specimens in the titanium alloy Ti6242 and the characterization of build-up welds by evaluation of their microstructure, hardness survey and residual stress measurements. The crucial point with regard to the application of laser cladding to replace damaged titanium blisks blades is the verification that the strength properties are not reduced. For this reason, another focus of this paper is on mechanical testing of laser clad specimens of Ti6242. Tensile and fatigue tests on conventional and blade-like specimens were performed. Both the tensile strength and the fatigue strength of laser clad specimens exceed the corresponding strength values of Ti6242 base material. Altogether the results show that laser cladding is a highly promising technology to restore damaged blades of titanium blisks.