Study of the Effect of Chrome Coating Layer to the Fatigue Strength of the Axial Machine Parts

Nowadays, electroplating is used widely in industry to enhance corrosion, abrasion resistance,… of machine elements. Chromium plating is the most widely used, especially in technology restores the machine element when it was worn. The chromium plating layer of machine element will make changes the mechanical characteristics of substrate. In this paper, the fatigue of the chromium plating machine element with 9 micrometer thicknesses and substrate (AISI 1045 steel) was studied. The results showed that fatigue life of machine part after chromium plating is less than uncoated machine element. Micro cracks on chromium coating layer lead to machine element quickly destroyed. In addition, X-ray diffraction techniques (CuKα radiation) is used to determine the haft-value breadth diffraction of chromium thin film at {211} diffraction plane. From the chart B - N relations could predict fatigue life of the machine parts.