Micro structure-Texture Evolution Studies on IMI 834 Titanium Alloy during High Pressure Torsion

IMI 834 titanium alloy is a near α (HCP) titanium alloy used for high temperature applications with the operating temperature up to 600OC. This alloy is extensively used in gas turbine engines such as high pressure compressor and low compressor discs, having desired with better dwell fatigue life and creep properties. These desired properties demands ultra fine grain micro structure with random crystallographic orientations i.e. random texture

Texture analyses of friction stir welded austenitic stainless steel AISI-316L

Low stacking fault energy AISI-316L stainless steel of 4 mm thick plates are friction stir welded at 1100 RPM and 8 mm/min welding speed using cubic boron nitride-tungsten rhenium composite tool. Large area orientation image mapping of the stir zone using electron backscatter diffraction scanning electron microscopy is performed to comprehensively characterise its microstructure and is searched for torsion shear texture components. Kernel average misorientation analysis revealed that top layer of the stir zone is almost fully recrystallised which experienced highest temperature and strain; middle layer has more deformed grains than recrystallised, showing partial recrystallisation while the bottom layer which encountered low strain but high temperature is almost fully recrystallised. Texture analyses showed variation from A {111} partial fiber type of texture in the top layer and C {001} and A {1 (Formula presented.) 1} type shear texture components in the middle layer followed by (Formula presented.) {1 (Formula presented.) 1} type of shear texture in the bottom layer. It is evident from Kernel average misorientation analysis and texture evolution studies that recrystallised region produced A {111} partial fiber/ (Formula presented.) {1 (Formula presented.) 1} shear component while deformed region produced C {001} shear component