Hierarchical microstructure strengthening in a single crystal high entropy superalloy

Development of a Refractory High Entropy Superalloy

Microstructure, phase composition and mechanical properties of a refractory high entropy superalloy, AlMo0.5NbTa0.5TiZr, are reported in this work. The alloy consists of a nano-scale mixture of two phases produced by the decomposition from a high temperature body-centered cubic (BCC) phase. The first phase is present in the form of cuboidal-shaped nano-precipitates aligned in rows along <100>-t...

Evaluating the Effect of Ta/W Ratio on Microstructure and Stress Rupture Properties of Ni-Based Single Crystal Superalloy PWA1483

In this study, the effect of Ta/W ratio on the microstructure and stress rupture properties of Ni-based single crystal (SX) superalloy PWA1483 was investigated. For this purpose, single crystal (SX) superalloys with different Ta/W ratios (0.75, 1.0, 1.32 and 1.5 in wt.%) were fabricated. The alloys were directionally solidified by Bridgman method under the same solidification condition at withd...

Fatigue crack initiation in a notched single-crystal superalloy component

In this paper, the fatigue crack initiation in notched single-crystal test specimens of material MD2 is investigated and analysed. A critical plane approach is adopted, in which the total strain ranges on the discrete slip planes are evaluated. Furthermore, a Coffin-Manson type of expression is used to describe the number of cycles to fatigue crack initiation. This relation is determined from a...

Joint Development of a Fourth Generation Single Crystal Superalloy

A new, fourth generation, single crystal superalloy has been jointly developed by GE Aircraft Engines, Pratt & Whitney and NASA. The focus of the effort was to develop a turbine airfoil alloy with long-term durability for use in the High Speed Civil Transport. In order to achieve adequate long-time strength improvements at moderate temperatures and retain good microstructural stability, it was ...

Creep and Stress Relaxation Anisotropy of a Single-Crystal Superalloy