1. 電(dian)凈液成(cheng)分見表4-42.
2. 電(dian)凈(jing)液的(de)性質和(he)用途
電凈(jing)液都是(shi)堿性溶(rong)液,pH為(wei)11~13.溶(rong)液呈(cheng)無色透明,手摸有滑感,-10℃不(bu)結冰。
電(dian)凈液具有較(jiao)強的去(qu)油作(zuo)(zuo)用,同(tong)時具有輕度的除氧化膜作(zuo)(zuo)用。
3. 使用方法
用鍍(du)(du)筆(bi)(bi)蘸上電凈(jing)液,大(da)型圓(yuan)柱形工(gong)(gong)件夾在(zai)機床車(che)頭上旋轉,鍍(du)(du)筆(bi)(bi)固定在(zai)刀(dao)架上不(bu)動(dong),將鍍(du)(du)筆(bi)(bi)和(he)工(gong)(gong)件接(jie)觸(chu),并保持一(yi)定的相(xiang)對(dui)運(yun)(yun)動(dong)速率,如果是平面工(gong)(gong)件,則工(gong)(gong)件固定,鍍(du)(du)筆(bi)(bi)在(zai)工(gong)(gong)件平面上接(jie)觸(chu),用手工(gong)(gong)移動(dong)保持相(xiang)對(dui)運(yun)(yun)動(dong)速率。在(zai)通電的情況下在(zai)工(gong)(gong)件表面涂抹,達到去(qu)油的目的。
工(gong)(gong)件(jian)(jian)與鍍筆之間的通電有(you)兩種方式:一(yi)(yi)種稱為正極性電凈(jing),工(gong)(gong)件(jian)(jian)接(jie)負極,鍍筆接(jie)正極,去油(you)效果快捷。通電時工(gong)(gong)件(jian)(jian)表面產生大量的氫(qing)(qing)氣,故工(gong)(gong)件(jian)(jian)有(you)滲氫(qing)(qing)現象(xiang);另一(yi)(yi)種稱為反極性電凈(jing),工(gong)(gong)件(jian)(jian)接(jie)正極,鍍筆接(jie)負極,通電時工(gong)(gong)件(jian)(jian)表面產生氧氣,其(qi)去油(you)效果中(zhong)等,作用(yong)溫和,沒有(you)滲氫(qing)(qing)現象(xiang)。在實際工(gong)(gong)作中(zhong),往(wang)往(wang)是采用(yong)高檔電壓(10~18V),先(xian)正極性電凈(jing)后反極性電凈(jing)聯合應用(yong),效果最佳(jia)。
4. 電凈工(gong)藝條(tiao)件
電壓10~18V,一般取12V;時間30~90s;電凈液(ye)溫度 15~50℃。
電凈(jing)后立(li)即用水沖洗干(gan)(gan)凈(jing),表(biao)(biao)面水膜分布均(jun)勻(yun),金屬(shu)表(biao)(biao)面呈(cheng)現(xian)均(jun)勻(yun)的潔(jie)凈(jing)狀態,立(li)即進行下道工序(xu),不可使(shi)表(biao)(biao)面形(xing)成干(gan)(gan)斑(ban)。