MICROSTRUCTURAL STUDY OF THE NEW INDUSTRIAL ALLOY (T16211) (TI 6W/O AL -2W/O NB -1 W/OTA 1W/O, MO), USING OPTICAL MICROSCOPY (OM) AND SCANNING ELECTRON MICROSCOPY (SEM)
Keywords:
Titanium, Basket weave microstructure, Alpha colony orthorhombic, MartensiteAbstract
Ti 6211 developed for marine and other engineering applications in harsh environment was characterized microstruturally using optical microscopy and the scanning electron microscopy.
Acicular, plate-like, lath and packet martensitic microstructures and basketweave or widmanstatten microstructures were observed on the optical micrographs. While martensitic microstructures were observed on samples heat treated at 800'c or 900°C or 1070°C, the basket weave or widmanstatten and alpha colony were observed on samples heat treated at 400°C, 500°C and 600C.
On the scanning electron images, films of supersaturated retained beta phase were observed along alpha plates while grain boundary alpha located along the grain boundaries and at the tri-junctions of the grains. These findings agreed with the literature on the microstructures observed in titanium alloys. As microstructures affect the material behaviour in engineering applications, the findings in this study will influence positively material design involving titanium.
