Investigation on High-Phosphorus Electroless Ni–P Plating Technology of Stainless Steel
The high-phosphorus electroless Ni–P plating was coated on the surface of stainless steel. Five parameters, which have much effect on coating quality, were chosen to optimize the high-phosphorus electroless Ni–P plating technology in L16(45) orthogonal test. By means of x-ray diffraction and scanning electron microscopy, the morphologies and phase structures of coating were analyzed. Furthermore, the mechanical properties of coating were studied by micro-hardness tester and universal friction-wear testing machine. The results reveal that the optimal technical parameters are as follows: 20 g•L-1 for NiSO4, 23 g•L-1 for NaH2PO2, 15 g•L-1 for C6H5O7Na3•2H2O, 8 g•L-1 for H2N-CH2-COOH, 10g•L-1 for CH3COONa, 7 g•L-1 for C4H6O4, with PH value of 4.6, which leads to perfect coating quality. Besides, the P content is 11.64 wt.%, i.e. a high-P coating. The micro-hardness of the coating is 550.67 HV and the wear loss, 4.7×10-3 g. The thermal shock test suggests that between coating and matrix exist a perfect cohesion, which is due to the homogenous and compact coating, with an amorphous structure, under the condition of the optimal technical parameters.
Yungang Li, Pengcheng Wang, Liqun Ai, Xiaoming Sang and Jinglong Bu
X. J. Wu et al., "Investigation on High-Phosphorus Electroless Ni–P Plating Technology of Stainless Steel", Advanced Materials Research, Vols. 291-294, pp. 129-132, 2011