An Advanced TiAl Alloy for High-Performance Racing Applications
Autor: | Janny Lindemann, Thomas Klein, Helmut Clemens, Holger Fellmann, Svea Mayer, Volker Güther, Michael Burtscher, Oliver Lehmann |
---|---|
Rok vydání: | 2020 |
Předmět: |
titanium aluminides
casting methods Materials science grains and interfaces 02 engineering and technology lcsh:Technology 01 natural sciences Article microstructural characterization 0103 physical sciences Ultimate tensile strength Formability General Materials Science intermetallics Composite material lcsh:Microscopy Ductility lcsh:QC120-168.85 fracture behavior 010302 applied physics Structural material lcsh:QH201-278.5 electron microscopy lcsh:T 021001 nanoscience & nanotechnology Microstructure Fatigue limit Superalloy lcsh:TA1-2040 lcsh:Descriptive and experimental mechanics fatigue lcsh:Electrical engineering. Electronics. Nuclear engineering Deformation (engineering) lcsh:Engineering (General). Civil engineering (General) 0210 nano-technology lcsh:TK1-9971 |
Zdroj: | Materials Volume 13 Issue 21 Materials, Vol 13, Iss 4720, p 4720 (2020) |
ISSN: | 1996-1944 |
Popis: | Requirements and strict regulations for high‑performance racing applications involve the use of new and innovative lightweight structural materials. Therefore, intermetallic &gamma ‑TiAl-based alloys enable new opportunities in the field due to their lower density compared to commonly used Ni‑base superalloys. In this study, a &beta ‑solidifying TiAl alloy was examined toward its use as structural material for inlet and outlet valves. The nominal composition of the investigated TNM alloy is Ti&ndash 43.5Al&ndash 4Nb&ndash 1Mo&ndash 0.1B (in at%), which enables an excellent formability at elevated temperatures due to the presence of bcc &beta ‑phase. Different hot‑extrusion tests on an industrial scale were conducted on the cast and hot isostatic pressed material to determine the ideal microstructure for the respective racing application. To simulate these operation conditions, hot tensile tests, as well as rotational bending tests, at room temperature were conducted. With a higher degree of deformation, an increasing strength and fatigue limit was obtained, as well as a significant increment of ductility. The fracture surfaces of the rotational bending test specimens were analyzed using scanning electron microscopy, revealing the relationship between crack initiation and microstructural constituents. The results of this study show that the mechanical performance of extruded TiAl material can be tailored via optimizing the degree of hot-extrusion. |
Databáze: | OpenAIRE |
Externí odkaz: | |
Nepřihlášeným uživatelům se plný text nezobrazuje | K zobrazení výsledku je třeba se přihlásit. |