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1、摘要化學鍍Ni-W-P鍍層具備硬度高、鍍層厚度均勻、耐蝕性且耐磨性好等優(yōu)勢,于是,制備優(yōu)質的鎳鎢合金鍍層近年來成為世界各國的鉆研的熱門。實驗采用化學鍍法制備了Ni-W-P合金鍍層,用SEM、XRD、電化學、點滴實驗、硬度等測試手段對其性能進行表征。在鋼鐵表面制備了Ni-W-P合金鍍層。研究了鎢酸鈉、硫酸鎳、次磷酸鈉、乳酸、溫度等工藝參數(shù)對化學鍍鎳層沉積速度、點滴時間、電化學性能等的影響,–1通過正交實驗優(yōu)化出了化學鍍Ni-W-P合金鍍層的較佳工藝配方:35g·L硫酸鎳,–1–1–1–1–115g·L鎢酸鈉,35g·L次亞磷酸鈉,30g·L硫酸銨,32g
2、·L檸檬酸鈉,8g·L–1–1–1蘋果酸,15ml·L乳酸,2-5mg·L碘酸鉀,1mg·L硫脲,鍍液pH值為4.8-5.1,溫度為88℃。制備的Ni-W-P合金鍍層結構呈現(xiàn)典型的高磷非晶態(tài),其磷含量達11.1%。Ni-W-P合金鍍層點滴時間為70s,耐蝕性略低于Ni-P鍍層的76s,但其硬度為679.18HV,較鎳磷合金鍍層(562.14HV)和基體(268.1HV)分別提高了約117.04HV和411.08HV。結合力測試結果發(fā)現(xiàn)Ni-W-P合金鍍層的結合力強于Ni-P鍍層。對制備的Ni-W-P合金鍍層進行熱處理。研究了200—800℃下熱處理對鍍
3、層性能的影響,結果表明隨著熱處理溫度的升高,鍍層由非晶態(tài)逐步轉化成為晶態(tài),硬度呈現(xiàn)先增大后減小的趨勢。當溫度達到400℃時,衍射峰增強,鍍層的胞狀物邊緣變得模糊,鍍層的硬度值最大為1070.1HV,磨損量最小為5.3mg?;瘜W鍍Ni-W-P合金鍍液的使用壽命。采用補加方法測出鍍液的循環(huán)壽命為-15MTO,在使用周期內鍍液的沉積速度穩(wěn)定在11μm·h以上,鍍態(tài)硬度在670HV左右。關鍵詞:化學鍍;Ni-W-P鍍層;鍍速;耐蝕性ABSTRACTElectrolessNi-W-Palloyplatingshavemanyadvantagessuchasgoo
4、dwearresistance,corrosionresistance,filmthicknessuniformity,highhardnessandsoon.Andhence,preparinggoodperformanceofNi-W-Palloycoatingbecomesahottopicinrecentyearsathomeandabroad.Inthisexperiment,theperformancesofNi-W-Palloycoatingpreparedonstainlesssteelsubstratehavebeentestedby
5、aseriesofmethodssuchasdriptest,thedepositionrate,micro-hardness,electrochemistry,scanningelectronmicroscopyandsoon.ElectrolessNi-W-Palloycoatingswerepreparedonstainlesssteel.Thesodiumtungstate,nickelsulfate,sodiumhypophosphite,lacticacid,temperatureandotherprocessparametersweres
6、tudiedonthedepositionrateofelectrolessnickelplatinglayer,theinfluenceofthebittime,theelectrochemicalproperties,etc.Theoptimumformulaacquiredbycombingwiththesinglefactorandorthogonalexperimentmethod-1-1areasfollowing:nickelsulfate35g·L,sodiumtungstate15g·L,hypophosphite-1-1-1-135
7、g·L,ammoniumsulfate30g·L,sodiumcitrate32g·L,malicacid8g·L,lactic-1-1-1acid15ml·L,potassiumiodate2-5mg·L,thiourea1mg·L,pH4.8to5.1,temperature88℃,time1.5h.ThestructureofNi-W-PalloyplatingistypicalcrystallinestatewithhighcontentofPelement(11.9%).Theresultsshowedthatthecorrosionrisi
8、stanceofNi-W-Palloyplating(driptime70s)isnearly