【摘要】 在含有二氧化锆的Ni-W-B电解液中,电沉积获得Ni-W-B/ZrO2复合镀层.用差示扫描量热分析(DSC)、X射线衍射(XRD)、扫描电子显微镜(SEM)和电化学技术较系统地研究了Ni-W-B/ZrO2复合镀层的电沉积、热处理过程,以及镀层的结构、表面形貌、显微硬度和耐腐蚀性能.结果表明,复合镀层的质量组成为Ni47.5%、W40.9%、B0.9%和ZrO210.7%.DSC和XRD结果清楚说明,二氧化锆对基质Ni-W-B镀层的结构有明显影响,使得复合镀层的非晶态结构特征更加明显.复合镀层比Ni-W-B合金有更高的显微硬度,呈现团粒状结构,晶块之间不存在裂纹但晶界清晰可辨;二氧化锆粒子分散于Ni-W-B基质镀层中.400℃、1h热处理后,Ni-W-B基质镀层中W向镀层表面偏析,镀层呈现固溶体晶态结构特征,表面形貌特征基本不变,复合镀层的显微硬度进一步提高,抗腐蚀性能增强,但镀层表层中的二氧化锆粒子大量脱落.更多还原

【Abstract】 Ni W B/ZrO2 composite coating was electrodeposited from the Ni W B electrolyte solution containing zirconia particles. The electrodeposition, heat treatment, structure, surface morphology, microhardness, and corrosion resistance of the composite coating were studied by means of differential scanning calorimeter(DSC), X ray diffraction(XRD),scanning electron microscopy(SEM),and electrochemical techniques. The results showed that the mass composition of the obtained Ni W B/ZrO2 composite coating was Ni 47.5%,W 40.9%, B 0.9%and ZrO2 10.7%. DSC combined with XRD results illustrated that zirconia took a remarkable influence on the structure of Ni W B matrix, leading the composite coating to a more obvious amorphous characteristics. The composite coating presented in higher microhardness compared to Ni W B alloy, granular structure with grain boundaries and crack free. Zirconia particles were dispersed in the Ni W B matrix. After heat treatment at 400 ℃for 1 h, surface morphology of the coating was kept almost no changes. The structure of the matrix was transferred to a crystal of Ni W solid solution, and W was segregated to the surface of the deposit. The microhardness and corrosion resistance were enhanced, whereas most of zirconia particles were gotten rid of from the surface layer.更多还原