摘要：本论文用脉冲复合电沉积的方法制备Ni-Mo-Er(Gd)-MoSi2复合镀层，研究了Er和Gd的浓度、正向占空比、施镀时间、正向电流密度、频率对Ni-Mo-Er(Gd)-MoSi2复合镀层的硬度影响，分别用电子扫描显微镜（SEM）、X射线衍射仪（XRD）、电子能谱仪（EDX），摩擦磨损试验机、热膨胀仪对该镀层进行表征。在MoSi2浓度为0.4g/50ml，表面活性剂浓度为0.09g/L下较佳工艺条件分别为：Er3+最佳浓度为0.3g/L、电流密度为18.75A/dm2，频率为2500Hz，占空比为1/2，施镀时间为20min；Gd3+最佳浓度为0.2g/L，电流密度为19.5A/dm2，频率为2500Hz，占空比为1/2，施镀时间为25min。在该条件下制备Ni-Mo-Er-MoSi2以及Ni-Mo-Gd-MoSi2镀层，测得的硬度分别为781.5HV以及877.88HV，与Ni-Mo-MoSi2复合镀层的硬度相比，其硬度均明显增大，分别增大了19.70%以及34.46%。从表征结果中可以知道Ni-Mo-Er(Gd)-MoSi2复合镀层相对于Ni-Mo-MoSi2复合镀层而言，镀层中的Mo含量分别增加12.38%和14.37%，且Si含量也分别增加了1.623%和2.613%。此外，Er和Gd分别进入复合镀层的晶格中，迫使晶格发生畸变，使衍射峰偏移，同时，它们也可以抑制Ni-Mo-Er(Gd)-MoSi2复合镀层的收缩，提高了镀层的耐高温性和耐磨性。而有关用脉冲复合电沉积的方法制备Ni-Mo-Er(Gd)-MoSi2复合镀层的文献还未见报道。7017
关键词：脉冲电沉积；Er；Gd；二硅化钼；复合镀层
Preparation of Ni-Mo-Er(Gd)-MoSi2 Composite Coating
Abstract: The paper is to use pulse plating method for the preparation of Ni-Mo-Er(Gd)-MoSi2 composite coating. The effects of the concentration of Er or Gd, positive duty cycle, plating time, the forward current density frequency of Ni-Mo-Er(Gd)-MoSi2 composite coating hardness were studied. We use a scanning electron microscope (SEM), X-ray diffraction (XRD), electron spectroscopy (EDX), friction and wear tester, thermal dilatometer to recive the characterization results of the composite coating. It shows that when the concentration of MoSi2 is 0.4g/50ml and the concentration of the surfactants is 0.09g/L, the optimal conditions were: Er3+ concentration is 0.3g/L, the current density is 18.75A/dm2, the frequency is 2500Hz, the duty cycle is 1/2 and the plating time is 20min; Dd3+ concentration is 0.2g/L, the current density is 19.5A/dm2, the frequency is 2500Hz, the duty cycle is 1/2 and the plating time is 25min. Under this condition, the hardness of the Ni-Mo-Er-MoSi2 and the Ni-Mo-Gd-MoSi2 composite coatings is 781.5HV and 877.88HV respectively. To campare with the Ni-Mo-MoSi2 composite coatings, the hardness of the Ni-Mo-Er(Gd)-MoSi2 is increased 12.38% and 14.37%. To characterize the Ni-Mo-Er(Gd)- MoSi2 composite coating ,we can know that to campare with the Ni-Mo-MoSi2 composite coatings, the content of Mo in the Ni-Mo-Er(Gd)-MoSi2 is increased 12.38% and 14.37% and the content of Si in the composite coatings is also increased 1.623% and 2.613%. Besides, Er and Gd enter the crystallattice of the composite coatings respectively, forcing the distortion of the crystallattice to occur, and the diffraction peak shift. They can also restrain the contraction of the Ni-Mo-Er(Gd)-MoSi2 composite coatings and enhance their heat-resisting quantity and its wear resistance. Besides, the current literatures about the preparation of the Ni-Mo-Er(Gd)-MoSi2 composite coating by pulse electrodeposition have not been reported.
Key Word: Pulse Electrodeposited; Er; Gd; MoSi2; composite coating
目 录
摘要 I
Abtract I
1. 引言 1
1.1 二硅化钼的性质及意义 1
1.2 复合镀的工艺现状 3
1.2.1自润滑复合镀层 3
1.2.2 电接触功能复合镀层 3
1.2.3 耐高温复合镀层 4
1.2.4 耐腐蚀复合镀层 4 Ni-Mo-Er(Gd)-MoSi2复合镀层的制备研究:http://www.751com.cn/huaxue/lunwen_4776.html