Oxidation behavior of electroless Ni-B coatings at 600 °C

In this study the oxidation behavior of electroless Ni-B coatings on steel CK45 was evaluated using TGA at 600 °C. Samples after the plating process heat treated at 400 °C for an hour. The rate of temperature increase 5 °C/min and the duration of sample isotherm temperature at about 3 h and Oxygen was selected as the gas inputTGA. According to data sets and also SEM images of cross-sections of the coatings showed that coatings at about 9,000 and 12,000 seconds influenced by temperature and oxidation have been crack and the amount and slope of weight more drastically changed in diagram TGA. The amount of change in weight after testing was 14 mg and the percent oxidation of the coating after the test was about 4%. Due to the high hardness of the coating HV1001085, high internal stresses causing failure part of the interface between coating and substrate.