Impact strength properties of nickel-based refractory superalloys at normal and elevated temperatures

✍ Scribed by E.B. Zaretsky; G.I. Kanel; S.V. Razorenov; K. Baumung

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 283 KB
• Volume: 31
• Category: Article
• ISSN: 0734-743X
• DOI: 10.1016/j.ijimpeng.2003.11.004

✦ Synopsis

The dynamic yield and fracture stress of two refractory alloys were measured under shock-wave loading at normal and elevated (up to 680 C) temperatures. The tested materials were polycrystalline nickel-based superalloy Inconel IN738LC and PWA 1483 Ni-Co-Fe alloy in quasi-monocrystalline state. Both alloys are used as turbine blade materials for the hot first stages of gas turbines. The alloys exhibit nonmonotonous dependence of the dynamic yield strength upon temperature with an abrupt increase in the temperature interval of 550-600 C. The dynamic tensile strength, in general, is less sensitive to temperature and shows less pronounced increase in the vicinity of 570 C. The observed anomalies of the dynamic strength properties correlate with anomalies in the heat capacity which are associated with the equilibrating of the short-range order in the g-matrix of the alloys.