Determination of Mechanical Properties for Laser Welded Turbine Rotor Assemblies for Automotive Turbocharger Applications

Abstract

To meet the demands of higher speeds, higher power density and the ability to adapt to harsh operating environments over a long period of time, structural designers use various materials to fabricate rotor parts for turbine assemblies. This introduces high requirements for stable rotation and rotor life. It is therefore important to analyse and determine the mechanical properties for a turbine rotor taking into account the manufacturing process. This paper focuses on laboratory mechanical testing for determination and analysis of turbine components consisting of a rotor, from 42CrMo4 (DIN EN 10083-3) and a turbine, made from Inconel 713C in laser welded assembly. The tests carried out consists of tensile testing for the turbine – rotor assembly, microhardness measurements, macro and microscopic examinations of the welded joint. The obtained results stand as a validation for the welding process technology used for this type of application ensuring the superior mechanical characteristics required for operation in harsh enviornments.