1. 電刷(shua)鍍錫目(mu)的物
15Cr11MoVA不銹(xiu)鋼套筒是汽(qi)輪(lun)機組上的重要零件(jian)。由(you)于它(ta)在高溫、高壓下長期工作,因而要求它(ta)的內部(bu)表(biao)面(mian)(mian)和小(xiao)(xiao)孔具有高強(qiang)度(du),高的抗蝕性(xing)和耐磨(mo)性(xing),而外部(bu)表(biao)面(mian)(mian)則要求具有良好的可加工性(xing)。為了滿足這些(xie)要求,對套筒內表(biao)面(mian)(mian)和小(xiao)(xiao)孔要進行氮化處理(li),而對其外部(bu)表(biao)面(mian)(mian)應采(cai)取鍍錫防(fang)滲(shen)氮措施。
2. 電刷鍍(du)錫工藝流程(cheng)
電(dian)(dian)凈(電(dian)(dian)凈溶(rong)(rong)液見表(biao)4-42中的 1號電(dian)(dian)凈液,工作(zuo)電(dian)(dian)16V,時間(jian)為(wei)電(dian)(dian)凈至(zhi)表(biao)面(mian)均(jun)勻潤濕不(bu)掛水(shui)(shui)珠為(wei)止)→水(shui)(shui)沖(chong)洗→活化(hua)(活化(hua)溶(rong)(rong)液成分(fen)(fen)硫酸 80g/L,硫酸銨110g/L,電(dian)(dian)壓(ya)為(wei)+12V,反(fan)接(jie),即工件接(jie)正(zheng)極(ji),鍍筆接(jie)負極(ji),表(biao)面(mian)活化(hua)至(zhi)均(jun)勻淺灰色后,變電(dian)(dian)壓(ya)為(wei)-12V,正(zheng)接(jie),即工件接(jie)負極(ji),表(biao)面(mian)活化(hua)至(zhi)均(jun)勻較深(shen)灰色為(wei)止)→水(shui)(shui)沖(chong)洗→刷鍍錫[鍍錫溶(rong)(rong)液成分(fen)(fen)參見4.9.12之(zhi)(3),工作(zuo)電(dian)(dian)壓(ya) 3~7V,溫(wen)度室溫(wen),陽極(ji)與工件之(zhi)間(jian)的相對運(yun)動速率為(wei)15~16m/min,錫層厚(hou)度為(wei) 6~7μm]→水(shui)(shui)→中和(用電(dian)(dian)凈液無(wu)電(dian)(dian)擦技(ji))→熱水(shui)(shui)授泡(溫(wen)度 50℃熱水(shui)(shui),時間(jian)5min)→干(gan)燥→氨化(hua)(鍍錫后3天內(nei))。
3. 刷(shua)鍍錫防(fang)滲氮出現問(wen)題(ti),可能原因及解(jie)決辦法見(jian)表 4- 47 。