X-ray characterization of inert gas atomized low carbon astroloy powder

X-ray studies were carried out on an inert gas atomized low carbon (LC) astroloy powder. The as-atomized powder was sieved into different fractions of narrow size using suitable combination of sieves to study the effect of particle size on the compositional homogeneity and lattice parameter. Using a slow scanning X-ray diffraction technique, the lattice parameter of the sample and broadening of the X-ray reflections were determined for different fractions. The results showed systematic variations with average particle size. The dendrite arm spacings measured by optical metallography showed a direct correlation with the average particle size. The observed broadening has been found to be due to the inhomogeneity in composition of the alloy developed during atomization.