三价铬钝化剂制备工艺的研究

摘要：本文利用电镀与钝化工艺进行三价铬钝化剂制备工艺的研究，研究了钝化剂中CoSO4•7H2O、CrCl3•6H2O、NH4F、NaNO3 、柠檬酸钠、Y(NO3)3、Pr2(SO4)3各浓度的选择。用电子能谱仪（EDX）、电子扫描显微镜（SEM）对添加Y3+、Pr3+、Co2+钝化剂的钝化层以及未钝化、厂家提供的钝化剂的钝化层分别进行表征。研究表明较佳工艺为：CoSO4•7H2O 2.6g/L、CrCl3•6H2O 12g/L、NH4F 0.4g/L、NaNO3 16g/L、柠檬酸钠12g/L、Y(NO3)3 0.5g/L、Pr2(SO4)3 0.1945g/L、电镀时间18s、钝化时间15s。钝化剂中添加Pr3+、Y3+、Co2+的钝化层较佳耐腐蚀时间分别为60s、59.13s、32.78s，添加Pr3+、Y3+钝化剂的钝化层耐腐蚀时间分别是添加Co2+钝化剂的钝化层耐腐蚀时间的1.83和1.8倍。钝化剂中添加Y3+后相对于添加Co2+的钝化层来说表面更加平整。可用Pr3+或Y3+代替Co2+作为钝化剂中的主盐。24208
毕业论文关键词：镀锌；三价铬；钝化；稀土
Study of trivalent chromium passivation solution
Abstract：Preparation of trivalent chromium passivation agent, this paper studies the passivator in NH4F, NaNO3, CoSO4•7H2O, CrCl3•6H2O, Sodium citrate, Y(NO3)3, Pr2(SO4)3 concentration on the corrosion resistance of the passivation layer, with electron spectrometer (EDX), scanning electron microscope (SEM) to add the Co2+,Pr3+,Y,3+ no passivation and the passivation solution of manufacturer, the passivation layer surface have been characterized, respectively. Determine the better technology conditions as follows: electroplating time 18s, passivation time 15s, CrCl3•6H2O 12g/L, NH4F 0.4g/L, NaNO3 16g/L, Sodium citrate 12g/L, Y(NO3)3 0.5g/L, Pr2(SO4)3 0.1945g/L, CoSO4•7H2O 2.6g/L. Passivator what added Pr3+, Y3+and Co2+ has better corrosion, and resistance of passivation time is 60 s, 59.13s, 32.78 s. The resistance of passivation time that add Pr3+, Y3+ passivation are 1.83 times and 1.8 times to Co2+. After the passivator added Y3+ for the passivation layer that adds Co2+ relatively more flat and level. Therefore Pr3+ or Y3+instead of Co2+can be used as main salt in the passivation agent.
Keywords: zinc plating ; Cr(Ⅲ); passivation ; REES
目录
1 前言    1
1.1 研究背景    1
1.2 镀锌层表面钝化处理技术    2
1.2.1低铬酸钝化    3
1.2.2高铬酸钝化    3
1.2.3 无铬钝化    3
1.2.4 三价铬钝化    3
1.3 三价铬钝化技术的发展及现状    4
1.4 稀土元素在电镀中的应用    5
1.5 钝化液配方的选择    6
1.5.1 主盐    6
1.5.2 络合剂    7
1.5.3 氧化剂    7
1.5.4 金属离子    7
1.5.5 表面活性剂    8
1.6 本文研究内容    8
2 实验部分    9
2.1 实验试剂与设备    9
2.1.1 实验试剂    9
2.1.2 实验设备    9
2.2 溶液的配置    9
2.2.1 出光液的配制    9
2.2.2 浸蚀液的配制    9
2.2.3 Y(NO3)3溶液的配置    10
2.2.4 Pr2(SO4)3溶液的配置    10
   2.3 工艺流程    10
   2.4 电镀与钝化工艺    10
   2.5 钝化剂中各组分浓度的选择    10
   2.5.1 CoSO4•7H2O浓度的选择    10
   2.5.2 CrCl3•6H2O浓度的选择    10
   2.5.3 NH4F浓度的选择    11
   2.5.4 柠檬酸钠浓度的选择    11 三价铬钝化剂制备工艺的研究:http://www.youerw.com/huaxue/lunwen_17606.html