Metals, which are especially used in the hot forging applications, are stable, when exposed to the atmosphere, at high and low temperatures. Metals such as iron, rusts and get oxidised very rapidly, while the other metals such as nickel, chromium corrode relatively slowly. Therefore it is important to study oxidation process along with film thickness of the oxide layer. The role of various alloying elements and its oxides during oxidation process need to be understood. Copper strongly influences the microstructure of micro alloyed steel since segregation of Cu occurs in steel during oxidation. Samples containing various Ni/Cu ratios are studied in SEM & XRD. Four samples of ratio of 1.8, 2.0, 2.5 and 5.0 with dimension size 25 mm × 25 mm are studied. The sample which has ratio of 1.8 gives better results since it shows minimal severity in cracking and optimum thickness is achieved.