Proceedings of the 6th International Conference on Mechanics and Materials in Design, Editors: J.F. Silva Gomes & S.A. Meguid, P.Delgada/Azores, 26-30 July 2015 -267- PAPER REF: 5653 HEAT TREATMENT EFFECT ON MICROSTRUCTURE AND PROPERTIES OF SINGLE CRYSTAL CMSX-4® NICKEL-BASED SUPERALLOY Andrzej Nowotnik (*) , Paweł Rokicki, Grzegorz Jakubowicz, Daniel Kurkowski, Grażyna Mrówka-Nowotnik, Małgorzata Wierzbińska, Jan Sieniawski, Jacek Nawrocki Department of Materials Science, Rzeszow University of Technology, Rzeszow, Poland (*) Email: [email protected]ABSTRACT Single crystal CMSX-4® nickel-based superalloy is one of the most popular representatives commonly used for manufacturing of aircraft engines hot-zone turbine blades. Although there are plenty of described procedures concerning heat treatment and final properties, literature presents loss of data in aim of description of microstructure modelling while the heat treatment process. Presented paper describes microstructure changes through different stages of heat treatment process namely: as-cast, annealed, precipitation hardened and aged. Additionally impression of mechanical properties change has been presented in form of micro-hardness measurements and creep testing. Keywords: heat treatment, single crystal, CMSX-4, superalloys, vacuum furnace. INTRODUCTION Gas turbine engine designers seek improved fuel efficiency power to weight performance, improved hot section durability and lower life cycle costs. To achieve the improved performance and efficiencies, designers tend to utilize increasingly capable single crystal alloys. Most popular in the described field is CMSX-4® . It is an ultra-high strength, single crystal alloy developed by the Cannon Muskegon Corporation. This second generation rhenium-containing, nickel-base single crystal alloy is capable of higher peak temperature/stress operation of at least 1163°C. Additionally it is capable to operate in long multiple cycles f.e. Solar® Turbines report blade lives to overhaul of 25,000 - 30,000 hours in their 15,000 hp Mars 100 industrial gas turbine. The aim of presented work is to investigate heat treatment effect on microstructure and properties of nickel-based single crystal superalloy CMSX-4®. Nickel-based single crystal superalloy CMSX-4® is commonly used for aircraft engines hot-zone turbine blades manufacturing. In the aircraft industry limitations there are no norms describing proper hat treatment procedures to obtain desired final parameters. Very problematic, especially in the aerospace industry, is phase transformation in high temperature and thus lowering of melting point of the alloy. Current paper presents complex microstructure investigation of CMSX-4® alloy after different stages of heat treatment process. RESULTS AND DISCUSSION To obtain most suitable surrounding parameters, different fixture materials and mounting methods have been investigated and their influence on the interface with the specimens and possibility for partial or full melt has been estimated. Most suitable heat treatment conditions
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HEAT TREATMENT EFFECT ON MICROSTRUCTURE AND ......of heat treatment process namely: as-cast, annealed, precipitation hardened and aged. Additionally impression of mechanical properties
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Proceedings of the 6th International Conference on Mechanics and Materials in Design,