1. 不(bu)銹鋼化學鍍銅的應用


 不銹鋼(gang)化學鍍(du)銅應用(yong)于電子工業、計算機工業及航空工業中電子元件的高(gao)效電磁干擾(rao)的屏(ping)蔽(bi)。



2. 不銹鋼基體上(shang)化學鍍銅(tong)存在的(de)問題


  香蕉視頻app連接:不銹鋼基體上化學鍍銅易造成鍍層鼓泡，這不僅影響了鍍層與基體的結合力，而且直接影響到外觀質量。為此，將鍍前酸處理過的不銹鋼放在烘箱中加熱，以除去酸洗時滲入到基體的氫，采用此方法解決了鍍層起泡問題，得到所需要的化學鍍銅層。



3. 不銹鋼(gang)化學鍍銅工藝流程


  NiCr不(bu)銹鋼（經過600℃真(zhen)空(kong)熱處理(li)(li)）→化學(xue)除油［氫氧化鈉（NaOH)10%(質(zhi)量分數）］→水(shui)洗→熱水(shui)洗→除銹（鹽酸(suan)(suan)1:1溶液，溫度(du)80~100℃,時(shi)(shi)間(jian)(jian)5min)→水(shui)洗→干(gan)燥→除氫（在烘箱中溫度(du)200℃,時(shi)(shi)間(jian)(jian)2h)→酸(suan)(suan)處理(li)(li)［稀硫酸(suan)(suan)5%(質(zhi)量分數），時(shi)(shi)間(jian)(jian)1~5min]→水(shui)洗→去離子水(shui)洗→化學(xue)鍍銅(tong)→水(shui)洗→抗銅(tong)變(bian)色處理(li)(li)（苯并(bing)三氮唑1g/L,溫度(du)65℃,時(shi)(shi)間(jian)(jian)2min)→純水(shui)洗→熱純水(shui)洗→干(gan)燥。



4. 化學鍍銅溶液成分及工(gong)藝條(tiao)件(jian)見表4-39


表 39.jpg



5. 化學鍍(du)銅溶液的配制


 先將硫酸(suan)銅(tong)(tong)和酒(jiu)石酸(suan)鉀鈉分別用(yong)(yong)純水(shui)溶(rong)(rong)(rong)(rong)解(jie)(jie)，然(ran)后(hou)將硫酸(suan)銅(tong)(tong)溶(rong)(rong)(rong)(rong)液在(zai)攪(jiao)(jiao)拌下(xia)加(jia)(jia)(jia)入(ru)酒(jiu)石酸(suan)鉀鈉溶(rong)(rong)(rong)(rong)液中，銅(tong)(tong)離(li)子(zi)(zi)被酒(jiu)石酸(suan)離(li)子(zi)(zi)絡合成(cheng)藍(lan)色絡合物。再將氯化(hua)鎳用(yong)(yong)少量水(shui)溶(rong)(rong)(rong)(rong)解(jie)(jie)后(hou)攪(jiao)(jiao)拌加(jia)(jia)(jia)入(ru)，再加(jia)(jia)(jia)入(ru)甲醛溶(rong)(rong)(rong)(rong)液，攪(jiao)(jiao)拌均勻(yun)。將氫氧化(hua)鈉用(yong)(yong)純水(shui)溶(rong)(rong)(rong)(rong)解(jie)(jie)成(cheng)200g/L 的(de)濃溶(rong)(rong)(rong)(rong)液待用(yong)(yong)。在(zai)開始(shi)(shi)化(hua)學鍍銅(tong)(tong)前(qian)，逐(zhu)步在(zai)攪(jiao)(jiao)拌下(xia)加(jia)(jia)(jia)入(ru)藍(lan)色絡合液中，使(shi)溶(rong)(rong)(rong)(rong)液pH達到12 左右（用(yong)(yong)9~13精密pH試紙測量），最后(hou)將穩定劑亞鐵氯化(hua)鉀、聚乙二醇用(yong)(yong)少量水(shui)溶(rong)(rong)(rong)(rong)解(jie)(jie)后(hou)攪(jiao)(jiao)拌加(jia)(jia)(jia)入(ru)，乙醇可(ke)直接加(jia)(jia)(jia)入(ru)，最后(hou)用(yong)(yong)純水(shui)加(jia)(jia)(jia)入(ru)至溶(rong)(rong)(rong)(rong)液的(de)規定體積，攪(jiao)(jiao)拌均勻(yun)后(hou)放入(ru)不銹鋼件(jian)即可(ke)開始(shi)(shi)化(hua)學鍍銅(tong)(tong)。



6. 操作要點


 ①. 裝載(zai)量


  按照每升(sheng)鍍液裝載(zai)2d㎡計(ji)算(suan)。


 ②. 除氫和攪拌(ban)


  不(bu)銹鋼(gang)(gang)對氫滲(shen)(shen)很(hen)(hen)敏感(gan)，工件(jian)在酸(suan)(suan)(suan)洗(xi)過(guo)程(cheng)(cheng)中(zhong)氫會(hui)(hui)滲(shen)(shen)人到(dao)基(ji)體(ti)(ti)(ti)中(zhong)，如果(guo)不(bu)除(chu)氫，化(hua)學(xue)鍍(du)銅(tong)鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)致密小孔覆(fu)蓋在不(bu)銹鋼(gang)(gang)表(biao)面(mian)(mian)后，氫氣無(wu)法逸出，造成很(hen)(hen)大(da)的(de)(de)(de)(de)(de)(de)應(ying)力，使鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)起(qi)泡，加上(shang)化(hua)學(xue)鍍(du)銅(tong)本身伴隨著析氫過(guo)程(cheng)(cheng)，氫氣會(hui)(hui)殘(can)留在基(ji)體(ti)(ti)(ti)與鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)金屬的(de)(de)(de)(de)(de)(de)晶格中(zhong)，增大(da)內應(ying)力，嚴(yan)重地(di)減弱(ruo)基(ji)體(ti)(ti)(ti)與鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)的(de)(de)(de)(de)(de)(de)結合強(qiang)度(du)。為(wei)此，從兩方面(mian)(mian)著手解決(jue)(jue)鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)起(qi)泡問題。其(qi)一是把經過(guo)去油、酸(suan)(suan)(suan)洗(xi)后的(de)(de)(de)(de)(de)(de)工件(jian)在化(hua)學(xue)鍍(du)銅(tong)前(qian)進行(xing)熱(re)(re)處(chu)理，除(chu)去滲(shen)(shen)入到(dao)基(ji)體(ti)(ti)(ti)中(zhong)的(de)(de)(de)(de)(de)(de)氫，熱(re)(re)處(chu)理溫(wen)度(du)和時(shi)(shi)(shi)(shi)間(jian)條件(jian)經實(shi)驗確定為(wei)180~200℃,2小時(shi)(shi)(shi)(shi)，鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)無(wu)鼓泡，鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)結合力合格。溫(wen)度(du)過(guo)低或時(shi)(shi)(shi)(shi)間(jian)過(guo)短仍有(you)輕微鼓泡，溫(wen)度(du)過(guo)高或時(shi)(shi)(shi)(shi)間(jian)過(guo)長都(dou)容易使表(biao)面(mian)(mian)再次(ci)生(sheng)成不(bu)易去除(chu)的(de)(de)(de)(de)(de)(de)氧化(hua)皮，又需要較長時(shi)(shi)(shi)(shi)間(jian)的(de)(de)(de)(de)(de)(de)強(qiang)酸(suan)(suan)(suan)處(chu)理，酸(suan)(suan)(suan)洗(xi)時(shi)(shi)(shi)(shi)氫會(hui)(hui)再次(ci)滲(shen)(shen)入基(ji)體(ti)(ti)(ti)。在所選定的(de)(de)(de)(de)(de)(de)溫(wen)度(du)和時(shi)(shi)(shi)(shi)間(jian)下雖表(biao)面(mian)(mian)會(hui)(hui)有(you)新的(de)(de)(de)(de)(de)(de)氧化(hua)膜生(sheng)成，但使用(yong)(yong)稀硫酸(suan)(suan)(suan)短時(shi)(shi)(shi)(shi)間(jian)酸(suan)(suan)(suan)洗(xi)即(ji)可(ke)，以免再次(ci)滲(shen)(shen)氫。其(qi)二(er)是在化(hua)學(xue)鍍(du)銅(tong)過(guo)程(cheng)(cheng)中(zhong)，采(cai)用(yong)(yong)某種攪拌(ban)（空氣攪拌(ban)或機械攪拌(ban)），有(you)利于銅(tong)離子向工件(jian)表(biao)面(mian)(mian)擴散，防止和減少副反(fan)應(ying)產(chan)(chan)物(wu)銅(tong)粉(fen)（即(ji)Cu2O)的(de)(de)(de)(de)(de)(de)生(sheng)成，而且有(you)利于反(fan)應(ying)產(chan)(chan)物(wu)氫氣脫離工件(jian)表(biao)面(mian)(mian)。通(tong)過(guo)上(shang)述(shu)兩種方法有(you)效(xiao)地(di)解決(jue)(jue)了(le)鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)鼓泡問題，提高了(le)鍍(du)層(ceng)(ceng)(ceng)(ceng)(ceng)(ceng)與基(ji)體(ti)(ti)(ti)的(de)(de)(de)(de)(de)(de)結合強(qiang)度(du)。


 ③. 催(cui)化(hua)活性(xing)劑-鎳離子


  在化(hua)學(xue)鍍銅溶(rong)液中加入(ru)少量(liang)鎳離子后，鍍層性(xing)質得(de)到改善，在鍍銅層中含(han)有微(wei)量(liang)的鎳，形(xing)成Cu89Ni11金屬(shu)化(hua)合物，它具有最佳的催化(hua)活性(xing)，提高(gao)鍍層的催化(hua)活性(xing)。


④. 穩定(ding)劑的控制


  在(zai)化學鍍(du)銅(tong)(tong)過(guo)程(cheng)中，甲醛(quan)能將二價銅(tong)(tong)離子還原為金屬銅(tong)(tong)鍍(du)層，還存在(zai)有(you)副反(fan)(fan)應，即(ji)不完全(quan)反(fan)(fan)應生成暗紅色的(de)(de)(de)氧化亞銅(tong)(tong)（Cu2O),它形成微粒(li)懸浮在(zai)鍍(du)液(ye)(ye)中，呈(cheng)膠體狀態，極難用(yong)過(guo)濾除(chu)去，若與銅(tong)(tong)共沉積，使(shi)銅(tong)(tong)鍍(du)層疏松粗糙，與基體結合力極差。氧化亞銅(tong)(tong)被甲醛(quan)還原成金屬微粒(li)，又(you)成為自催化中心(xin)，使(shi)鍍(du)液(ye)(ye)自發分解，消耗了(le)鍍(du)液(ye)(ye)中的(de)(de)(de)有(you)效成分。為了(le)抑制副反(fan)(fan)應的(de)(de)(de)發生，加入穩(wen)定(ding)劑(ji)，以提(ti)高鍍(du)液(ye)(ye)的(de)(de)(de)穩(wen)定(ding)性(xing)。但(dan)是，過(guo)量(liang)的(de)(de)(de)穩(wen)定(ding)劑(ji)的(de)(de)(de)加人，又(you)成了(le)化學鍍(du)銅(tong)(tong)反(fan)(fan)應的(de)(de)(de)催化毒(du)性(xing)劑(ji)，顯著降低化學鍍(du)的(de)(de)(de)速率(lv)，甚至停鍍(du)，故選用(yong)穩(wen)定(ding)劑(ji)，并控制其很低的(de)(de)(de)適宜含(han)量(liang)，對(dui)提(ti)高鍍(du)液(ye)(ye)穩(wen)定(ding)性(xing)有(you)效。


⑤. 防銅層變(bian)色處(chu)理


  對銅(tong)層(ceng)(ceng)(ceng)進(jin)行防(fang)變(bian)(bian)色處理，在鍍(du)銅(tong)層(ceng)(ceng)(ceng)表面形(xing)成(cheng)一層(ceng)(ceng)(ceng)穩定的(de)絡(luo)合膜(mo)，隔絕外界浸(jin)蝕性物質對鍍(du)銅(tong)層(ceng)(ceng)(ceng)的(de)作用，使(shi)鍍(du)銅(tong)層(ceng)(ceng)(ceng)保持本色一定的(de)時(shi)間(jian)。苯并三氮唑要(yao)先用乙醇溶解(jie)好，然后加入熱蒸餾水中。防(fang)變(bian)(bian)色處理的(de)溫度不(bu)低于65℃,時(shi)間(jian)不(bu)少(shao)于2min,否則防(fang)變(bian)(bian)色達不(bu)到效果。



7. 鍍(du)層(ceng)結合(he)強(qiang)度檢(jian)測－劃痕實驗法


 在(zai)鍍(du)(du)層表(biao)面(mian)用(yong)刀(dao)片劃(hua)出1mm間距的直行(xing)線和90°交(jiao)錯(cuo)的橫行(xing)線形成(cheng)小方格(ge)。觀(guan)察劃(hua)痕交(jiao)錯(cuo)處(chu)鍍(du)(du)層有無起層，進一步用(yong)黏(nian)性高的膠帶(dai)(dai)貼于劃(hua)痕表(biao)面(mian)，再(zai)撕下膠帶(dai)(dai)，以銅層不脫落為合格(ge)。



8. 不(bu)銹(xiu)鋼化學(xue)鍍銅常見故障、可能(neng)原因及糾正(zheng)方(fang)法見表4-40.


表 40.jpg