Electroless Ni-P plating and Heat Treatments on S45C Carbon Steel

This research focused on the effects of S45C carbon steel using different pH values of electroless Ni-P plating. The experimental results show that the specimens using acid and alkaline baths of pH5 and pH8 of Ni-P deposition can acquire a higher hardness; the hardness values were the HV0.05 701 and HV0.05 803, respectively. Moreover, for pH5 and pH8 of Ni-P deposition with heat treatment of 350°C and 300°C and soaking for 1 hr, the highest level of hardness appeared in HV0.05 1027 and HV0.05 1066, respectively. The specimens underwent the main precipitate phase of Ni3P after heat treatment. Due to precipitation, strengthening of the Ni3P phase increased the surface hardness of specimens after heat treatment; thus, the wear depth was decreased and wear resistance was enhanced. The optimal process appeared in Ni-P deposition by pH5 and pH8 after 350°C and 300°C heat treatment and for 1 hr of soaking, respectively.