Effect of aluminum on mechanical solid-state alloying of iron with nitrogen in ball mill

Abstract

Mossbauer spectroscopy and X-ray diffraction analysis have been used to study mechanical solidstate alloying with nitrogen and chromium of iron and an Fe-3Al alloy in the process of the mechanical activation with chromium nitrides in a ball mill. It is shown that the deformation-induced dissolution of chromium nitrides in iron and Fe-3Al matrices results in the formation of substitutional chromium and interstitial nitrogen solid solutions. The alloying of iron with aluminum accelerates the process of the deformation-induced dissolution of chromium nitrides, but reduces the nitrogen content in the interstitial solid solution. Post-deformation annealing generally leads to the escape of aluminum from the matrix, the substitution of chromium for aluminum, and the formation of fine nitrides AlN.