One possibility to improve the fatigue life and strength of metallic materials is shot peening. However, at elevated temperatures, induced residual stresses may relax. To investigate influence peening on high-temperature behavior, isothermal tests were conducted shot-peened untreated samples gamma TiAl 48-2-2 750 °C in air. The material was characterized using EBSD, microhardness, stress analys...

A multi-year effort has been focused on optimizing the long-term oxidation performance of ingot-processed (IP) and oxide-dispersion strengthened (ODS) Fe3Al and iron aluminidebased coatings. Based on results from several composition iterations, a Hf-doped alloy (Fe28Al-2Cr-0.05at.%Hf) has been developed with significantly better high temperature oxidation resistance than other iron aluminides. ...

The fractional concentration of Ni-vacancies in NiAl at high temperature has been determined for compositions between 50 and 53 at.% Ni from measurements using perturbed angular correlation of gamma rays (PAC). The vacancies were detected by quadrupole interactions induced at nearby In/Cd impurity probes present on the Al sublattice in high dilution. One set of measurements was made at high tem...

Gamma titanium aluminide has received significant attention in recent years as a candidate material for use in aerospace and industrial gas turbine engine applications. In particular, these materials offer significant weight reductions (densities are less than half that of nickel-based superalloys), high specific strength retention at elevated temperature and high specific stiffness which is pa...

Nickel superalloys are the main materials used in manufacturing of turbine blades and vanes aero-space industry. They works is extremely high temperature a corrosive environment (oxidation, hot corrosion) undergo several different thermo-mechanical loads. Aluminide coatings method protection surface nickel against exhaust gasses jet en-gine. In presented article microstructural characterization...

Thermal cycling of a platinum modified, nickel aluminide (Ni,Pt)Al coated single crystal superalloy, between 1000 and 1150 C with 10 min holds at each temperature, and subject to a compressive uniaxial stress is reported. There are two major effects of the superimposed compressive stress not observed in the absence of the stress. One is that the rumpling pattern exhibits an asymmetry with an in...

Perturbed angular correlation of gamma rays was applied to determine properties of equilibrium defects in B2 NiAl near the stoichiometric composition. Point defects were detected through quadrupole interactions they induce at In probe atoms on the Al sublattice. Well-resolved signals were observed for probe atoms having zero, one or two Ni-vacancies (VNi) in the first neighbor shell. The fracti...