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电沉积Ni-Mo(-Sm)镀层工艺的研究+文献综述

时间:2017-02-28 21:59来源:毕业论文
论文利用脉冲电镀法制备了Ni-Mo镀层和Ni-Mo-Sm镀层,分别研究了pH值、温度、电流密度、频率、占空比、时间、转速及Sm3+浓度等因素对镀层硬度的影响,并分别用扫描电镜(SEM)、能谱仪

摘要:本论文利用脉冲电镀法制备了Ni-Mo镀层和Ni-Mo-Sm镀层,分别研究了pH值、温度、电流密度、频率、占空比、时间、转速及Sm3+浓度等因素对镀层硬度的影响,并分别用扫描电镜(SEM)、能谱仪(EDX)、X-射线衍射仪(X-RD)和摩擦磨损仪对镀层表面形貌、组成、结构和耐磨性进行表征。研究结果表明,制备Ni-Mo镀层的较佳工艺条件是pH为6.7、温度为25℃、电流密度为0.76A/dm2、脉冲频率为5000Hz、占空比为1/2、转速为300r/min、反应时间为20min,在该条件下获得的Ni-Mo镀层硬度为707.86HV。制备Ni-Mo-Sm镀层的较佳工艺条件是pH为6.7、温度为25℃、电流密度为0.74A/dm2、脉冲频率为5000Hz、占空比为1/2、转速为350r/min、反应时间为20min,在该条件下获得的Ni-Mo-Sm镀层硬度为760.42HV,其硬度比Ni-Mo镀层提高了7.43%,且Ni-Mo-Sm镀层晶粒更细,表面更平整致密,晶型结构更完整,耐磨性能更好。目前脉冲电镀Ni-Mo-Sm镀层的研究还未见报道。6195
关键词:脉冲电镀;稀土元素;钼镍合金;摩擦磨损
The technical research of pulse plating of Ni-Mo(-Sm)
Abstract:In this thesis, using pulse electroplating method of preparing Ni-Mo and Ni-Mo-Sm coating , through the single factor experiment study of different parameters ( pH value, temperature, current density, frequency, duty ratio, time, speed and Sm3+ concentration and other factors) on hardness of coating and deposition rate influence, and were used to scan electron microscope ( SEM ), energy dispersive spectrometer ( EDX ), X- ray diffraction ( X-RD ), thermal expansion instrument ( DIL ) and friction and wear tester on the coating surface morpHology, composition, structure, thermal expansion coefficient and wear resistance of. Research results show that When pH was 6.7, temperature was 25℃, the current density is0.76A/dm2, pulse frequency is 5000Hz, the ratio is 1/2, the speed is 300r/min, the reaction time is 20min,the hardness of the coating, the Ni-Mo707.86HV maximum. When in bath by adding Sm3+ when the hardness of the coating are improved to different degrees. When pH was 6.7, temperature was 25℃, the current density is0.74A/dm2, pulse frequency is 5000Hz, the ratio is 1/2, the speed is 350r/min, the reaction time is 20min, and the maximum hardness of the Ni-Mo-Sm coating is 760.42 HV , Ni-Mo-Sm oating grain finer, more surface formation of dense, coating of molybdenum content higher, crystalline structure is more complete, the high temperature resistant and wear resistant performance.
Keywords: Pulse electroplating; rare earth element; molybdenum nickel alloy; coefficient of friction
目  录
1  引言    1
1.1 镍金属的性质及应用    1
1.1.1 镍金属的概述    1
1.1.2 金属镍的开发利用现状    1
1.1.3 镍合金的概述及开发利用现状    2
1.2 钼金属的性质及应用    3
1.2.1 钼金属的概述    3
1.2.2 金属钼的利用现状    4
1.3 脉冲电镀的和优点    4
1.4 稀土元素在电沉积中的发展状况    5
1.5 本文主要研究内容    6
2 实验部分    7
2.1 实验材料与设备    7
2.1.1 实验材料    7
2.1.2 实验设备    7
2.2 实验装置    8
2.3 工艺流程    8
2.3.1 电镀液组成    8
2.3.2 电镀流程    9
2.4 电镀工艺条件的选择    10
2.4.1 电镀Ni-Mo镀层工艺条件的选择    10
2.4.2 电镀Ni-Mo-Sm镀层工艺条件的选择    11
2.5 镀层性能测试及表征    11
2.5.1 镀层硬度的测定    12 电沉积Ni-Mo(-Sm)镀层工艺的研究+文献综述:http://www.751com.cn/huaxue/lunwen_3561.html
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