1. 電刷鍍錫目的(de)物(wu)

 15Cr11MoVA不銹鋼套筒是汽(qi)輪機組上的(de)(de)重要(yao)(yao)(yao)零件。由(you)于它(ta)在高(gao)(gao)(gao)溫(wen)、高(gao)(gao)(gao)壓下長期(qi)工作，因而要(yao)(yao)(yao)求(qiu)它(ta)的(de)(de)內部表(biao)面(mian)和小(xiao)孔具有高(gao)(gao)(gao)強度(du)，高(gao)(gao)(gao)的(de)(de)抗蝕性和耐磨性，而外(wai)部表(biao)面(mian)則要(yao)(yao)(yao)求(qiu)具有良好的(de)(de)可加工性。為了滿足(zu)這些要(yao)(yao)(yao)求(qiu)，對(dui)套筒內表(biao)面(mian)和小(xiao)孔要(yao)(yao)(yao)進行(xing)氮(dan)化處理，而對(dui)其外(wai)部表(biao)面(mian)應采取(qu)鍍錫(xi)防滲氮(dan)措施。

2. 電刷鍍錫工藝流程

  電(dian)(dian)(dian)凈(jing)(jing)（電(dian)(dian)(dian)凈(jing)(jing)溶液(ye)(ye)見表(biao)(biao)4-42中(zhong)的(de) 1號電(dian)(dian)(dian)凈(jing)(jing)液(ye)(ye)，工(gong)作電(dian)(dian)(dian)16V,時間為(wei)電(dian)(dian)(dian)凈(jing)(jing)至表(biao)(biao)面均(jun)勻潤(run)濕不掛水珠為(wei)止）→水沖洗→活(huo)化(hua)(hua)（活(huo)化(hua)(hua)溶液(ye)(ye)成分(fen)硫酸 80g/L,硫酸銨(an)110g/L,電(dian)(dian)(dian)壓(ya)為(wei)＋12V,反(fan)接(jie)，即(ji)工(gong)件(jian)接(jie)正極(ji)，鍍筆接(jie)負極(ji)，表(biao)(biao)面活(huo)化(hua)(hua)至均(jun)勻淺灰(hui)色后(hou)，變電(dian)(dian)(dian)壓(ya)為(wei)－12V,正接(jie)，即(ji)工(gong)件(jian)接(jie)負極(ji)，表(biao)(biao)面活(huo)化(hua)(hua)至均(jun)勻較深灰(hui)色為(wei)止）→水沖洗→刷(shua)鍍錫(xi)［鍍錫(xi)溶液(ye)(ye)成分(fen)參見4.9.12之（3)，工(gong)作電(dian)(dian)(dian)壓(ya) 3~7V,溫(wen)度(du)室溫(wen)，陽(yang)極(ji)與工(gong)件(jian)之間的(de)相對運動速率為(wei)15~16m/min,錫(xi)層厚(hou)度(du)為(wei) 6~7μm]→水→中(zhong)和（用(yong)電(dian)(dian)(dian)凈(jing)(jing)液(ye)(ye)無電(dian)(dian)(dian)擦技(ji)）→熱水授泡（溫(wen)度(du) 50℃熱水，時間5min)→干燥→氨化(hua)(hua)（鍍錫(xi)后(hou)3天內）。

3. 刷鍍錫防(fang)滲(shen)氮出現問題，可能(neng)原因(yin)及解決辦法(fa)見表 4- 47 。