【摘要】：近年來,工業(yè)生產(chǎn)中得到的Ni-Cr合金鍍層中Cr含量較低,厚度薄,難以很好的滿足材料在惡劣環(huán)境中的要求。研究發(fā)現(xiàn),錳元素能夠提高不同合金體系的耐蝕性能。為提高Q235鋼的耐蝕性,采用脈沖電鍍法在Q235鋼表面制備Ni-Cr-Mn合金鍍層。利用輝光放電光譜儀、掃描電鏡、Tafel曲線和電化學(xué)阻抗譜,研究鍍液組分、配位劑、添加劑、鍍液溫度、pH值、電流密度、電鍍時(shí)間、占空比和電沉積方式對(duì)鍍層元素組成、沉積速率、表面形貌和耐蝕性的影響,確定了最優(yōu)鍍液組成和最優(yōu)工藝參數(shù)。最優(yōu)鍍液組成:NiSO_4·6H_2O、CrCl_3·6H_2和MnSO_4·H_2O摩爾比為3:5:10,最優(yōu)復(fù)合配位劑A含量為0.35 mol/L。最優(yōu)工藝參數(shù):溫度40℃,pH值2.6,電流密度13 A/dm~2,時(shí)間30 min,占空比20%。采用直流、單脈沖和換向脈沖三種電沉積方式制備的合金鍍層中,換向脈沖方式制備的合金鍍層表面粗糙度最低,耐蝕性最好。利用極化曲線、循環(huán)伏安曲線和計(jì)時(shí)電流曲線研究了硫酸鹽-氯化物體系NiCr-Mn合金的電沉積行為。表明Ni-Cr-Mn合金沉積為不可逆過程,合金鍍層具有較好的耐蝕性。
[Abstract]:In recent years, the content of Cr in the coating of Ni-Cr alloy obtained in industrial production is relatively low and the thickness is thin, so it is difficult to meet the requirements of the materials in the harsh environment. It is found that mn can improve the corrosion resistance of different alloy systems. In order to improve the corrosion resistance of Q235 steel, Ni-Cr-Mn alloy coating was prepared on Q235 steel surface by pulse electroplating. By means of glow discharge spectrometer, scanning electron microscope, Tafel curve and electrochemical impedance spectroscopy, the composition of plating solution, coordination agent, additive, bath temperature, pH value, current density, electroplating time, duty cycle and electrodeposition mode were studied. The effects of deposition rate, surface morphology and corrosion resistance on the optimum bath composition and process parameters were determined. The optimum composition of plating bath is: NiSO_4 6H _ 2O _ 2O _ CrCl _ 3 6H_2 and MnSO_4 H _ 2O molar ratio is 3: 5: 10, and the optimum compound coordination agent A content is 0.35 mol/L. The optimum process parameters are as follows: temperature 40 鈩，

本文編號(hào)：2306226