1. 電凈液成分見表4-42.
2. 電凈液的性質和(he)用(yong)途(tu)
電凈液都(dou)是堿性溶(rong)液,pH為11~13.溶(rong)液呈(cheng)無色透明(ming),手摸有滑感,-10℃不結冰(bing)。
電(dian)凈(jing)液(ye)具有(you)較強的去油(you)作用,同時具有(you)輕度(du)的除氧化膜作用。
3. 使用方法
用鍍(du)(du)筆(bi)蘸上(shang)(shang)電凈液,大型圓柱形(xing)工(gong)件(jian)夾(jia)在(zai)(zai)機床車(che)頭上(shang)(shang)旋轉,鍍(du)(du)筆(bi)固定在(zai)(zai)刀架上(shang)(shang)不動(dong),將鍍(du)(du)筆(bi)和工(gong)件(jian)接觸,并保持一定的(de)相(xiang)對運動(dong)速(su)率,如(ru)果是平面(mian)工(gong)件(jian),則工(gong)件(jian)固定,鍍(du)(du)筆(bi)在(zai)(zai)工(gong)件(jian)平面(mian)上(shang)(shang)接觸,用手工(gong)移動(dong)保持相(xiang)對運動(dong)速(su)率。在(zai)(zai)通電的(de)情況下在(zai)(zai)工(gong)件(jian)表面(mian)涂抹,達到去油的(de)目的(de)。
工(gong)件與鍍(du)筆(bi)(bi)之間的(de)通電(dian)(dian)(dian)有(you)兩種(zhong)(zhong)方式:一種(zhong)(zhong)稱(cheng)為正極(ji)(ji)性(xing)電(dian)(dian)(dian)凈,工(gong)件接(jie)負極(ji)(ji),鍍(du)筆(bi)(bi)接(jie)正極(ji)(ji),去油效果(guo)快捷。通電(dian)(dian)(dian)時工(gong)件表面產生大量的(de)氫(qing)(qing)氣,故工(gong)件有(you)滲(shen)(shen)氫(qing)(qing)現象;另(ling)一種(zhong)(zhong)稱(cheng)為反極(ji)(ji)性(xing)電(dian)(dian)(dian)凈,工(gong)件接(jie)正極(ji)(ji),鍍(du)筆(bi)(bi)接(jie)負極(ji)(ji),通電(dian)(dian)(dian)時工(gong)件表面產生氧氣,其去油效果(guo)中等,作(zuo)用溫和,沒(mei)有(you)滲(shen)(shen)氫(qing)(qing)現象。在(zai)實際工(gong)作(zuo)中,往往是采用高檔電(dian)(dian)(dian)壓(10~18V),先正極(ji)(ji)性(xing)電(dian)(dian)(dian)凈后反極(ji)(ji)性(xing)電(dian)(dian)(dian)凈聯(lian)合(he)應用,效果(guo)最佳。
4. 電凈工藝條件
電壓10~18V,一(yi)般(ban)取12V;時間(jian)30~90s;電凈液(ye)溫度 15~50℃。
電凈(jing)后立(li)即(ji)用(yong)水沖洗干凈(jing),表(biao)面水膜分布均勻,金屬表(biao)面呈現均勻的潔凈(jing)狀態,立(li)即(ji)進行下道工序,不可(ke)使表(biao)面形(xing)成干斑。