對(dui)黃銅脫鋅(xin)腐蝕(shi)的機理(li),國內外(wai)都做了一(yi)(yi)些研究(jiu)(jiu),提出了各種研究(jiu)(jiu)結論(lun),但目前(qian)還不十(shi)分完善,主要理(li)論(lun)有優先(xian)溶解(jie)(jie)和溶解(jie)(jie)-再沉積機制(zhi)(zhi)、雙空位(wei)機制(zhi)(zhi)和滲流機制(zhi)(zhi)。接下(xia)就讓我們來簡單的介紹一(yi)(yi)下(xia)這些機制(zhi)(zhi)。         

 1. 優(you)先(xian)溶解(jie)和(he)溶解(jie)一再沉積機制，優(you)先(xian)(xian)溶解機制認(ren)為,黃(huang)銅(tong)(tong)(tong)腐蝕過(guo)程中(zhong),合金表面(mian)的(de)(de)(de)(de)(de)(de)鋅(xin)(xin)(xin)從黃(huang)銅(tong)(tong)(tong)中(zhong)優(you)先(xian)(xian)溶解,然(ran)后(hou)合金內(nei)部的(de)(de)(de)(de)(de)(de)鋅(xin)(xin)(xin)通過(guo)空(kong)位(wei)(wei)擴散繼續(xu)溶解,電位(wei)(wei)較正的(de)(de)(de)(de)(de)(de)銅(tong)(tong)(tong)被遺留下來,呈疏松狀的(de)(de)(de)(de)(de)(de)銅(tong)(tong)(tong)層(ceng)。但這種理論(lun)難(nan)以說明(ming)脫(tuo)鋅(xin)(xin)(xin)造成的(de)(de)(de)(de)(de)(de)脆性(xing)(xing)開(kai)裂(lie)深度與(yu)鋅(xin)(xin)(xin)在(zai)(zai)室溫下擴散系數太低之間的(de)(de)(de)(de)(de)(de)矛盾。而(er)在(zai)(zai)黃(huang)銅(tong)(tong)(tong)表面(mian)與(yu)溶液接(jie)觸處發生(sheng)了鋅(xin)(xin)(xin)選(xuan)擇性(xing)(xing)溶解,被腐蝕的(de)(de)(de)(de)(de)(de)鋅(xin)(xin)(xin)由合金晶格上鋅(xin)(xin)(xin)原子(zi)的(de)(de)(de)(de)(de)(de)擴散所補償(chang),鋅(xin)(xin)(xin)在(zai)(zai)活性(xing)(xing)脫(tuo)鋅(xin)(xin)(xin)前沿被選(xuan)擇性(xing)(xing)侵蝕,這個前沿不斷地向內(nei)部移動。按照(zhao)作者的(de)(de)(de)(de)(de)(de)觀點,脫(tuo)鋅(xin)(xin)(xin)相(xiang)只是在(zai)(zai)初始黃(huang)銅(tong)(tong)(tong)母體的(de)(de)(de)(de)(de)(de)骨架結構中(zhong)出現,它容許鋅(xin)(xin)(xin)離子(zi)自由向外擴散,黃(huang)銅(tong)(tong)(tong)的(de)(de)(de)(de)(de)(de)脫(tuo)鋅(xin)(xin)(xin)阻力依賴于(yu)鋅(xin)(xin)(xin)外層(ceng)電子(zi)離開(kai)鋅(xin)(xin)(xin)原子(zi)的(de)(de)(de)(de)(de)(de)難(nan)易程度。    

 2. 溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)-再沉積機(ji)制(zhi)認為,黃銅(tong)(tong)(tong)(tong)表面上的(de)(de)(de)(de)鋅(xin)(xin)(xin)(xin)和(he)銅(tong)(tong)(tong)(tong)一起(qi)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie),鋅(xin)(xin)(xin)(xin)留在(zai)(zai)溶(rong)(rong)(rong)液中(zhong)，而銅(tong)(tong)(tong)(tong)在(zai)(zai)靠近溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)處的(de)(de)(de)(de)表面上迅速(su)析(xi)出而重(zhong)新沉積在(zai)(zai)基體上,但(dan)這種機(ji)制(zhi)無法圓滿地解(jie)(jie)(jie)(jie)釋銅(tong)(tong)(tong)(tong)不(bu)(bu)可(ke)能溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)時的(de)(de)(de)(de)脫(tuo)(tuo)鋅(xin)(xin)(xin)(xin)現(xian)象。因為鋅(xin)(xin)(xin)(xin)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)的(de)(de)(de)(de)電(dian)位遠低于(yu)(yu)銅(tong)(tong)(tong)(tong)的(de)(de)(de)(de)陽極(ji)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)電(dian)位,因此銅(tong)(tong)(tong)(tong)和(he)鋅(xin)(xin)(xin)(xin)不(bu)(bu)可(ke)能在(zai)(zai)任(ren)何情況(kuang)下發(fa)生(sheng)同時溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)的(de)(de)(de)(de)現(xian)象。在(zai)(zai)硫酸(suan)中(zhong)進(jin)行了(le)研(yan)究,在(zai)(zai)最初(chu)階段由于(yu)(yu)建立了(le)(Cu-Zn)原電(dian)池,鋅(xin)(xin)(xin)(xin)在(zai)(zai)溶(rong)(rong)(rong)液中(zhong)優先(xian)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie),但(dan)當多孔的(de)(de)(de)(de)銅(tong)(tong)(tong)(tong)-氧化銅(tong)(tong)(tong)(tong)膜在(zai)(zai)電(dian)極(ji)表面形成時,脫(tuo)(tuo)鋅(xin)(xin)(xin)(xin)速(su)度(du)(du)(du)下降(jiang),銅(tong)(tong)(tong)(tong)、鋅(xin)(xin)(xin)(xin)同時溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)。這時鋅(xin)(xin)(xin)(xin)的(de)(de)(de)(de)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)速(su)度(du)(du)(du)受(shou)通(tong)過晶(jing)格空位的(de)(de)(de)(de)擴散速(su)度(du)(du)(du)所控制(zhi),在(zai)(zai)這個階段銅(tong)(tong)(tong)(tong)的(de)(de)(de)(de)溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)速(su)度(du)(du)(du)因為CuO膜的(de)(de)(de)(de)形成而減少(shao),這決定性地位取決于(yu)(yu)腐蝕(shi)條件,比如在(zai)(zai)稀鹽(yan)酸(suan)中(zhong)會發(fa)生(sheng)鋅(xin)(xin)(xin)(xin)的(de)(de)(de)(de)選擇性溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie),而在(zai)(zai)濃(nong)度(du)(du)(du)較(jiao)高(gao)的(de)(de)(de)(de)鹽(yan)酸(suan)或海水(shui)中(zhong)則發(fa)生(sheng)銅(tong)(tong)(tong)(tong)重(zhong)新析(xi)出的(de)(de)(de)(de)脫(tuo)(tuo)鋅(xin)(xin)(xin)(xin)腐蝕(shi)。此外,脫(tuo)(tuo)鋅(xin)(xin)(xin)(xin)機(ji)制(zhi)還受(shou)到溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie)溫度(du)(du)(du)、浸泡周期長短的(de)(de)(de)(de)影響(xiang)。銅(tong)(tong)(tong)(tong)和(he)鋅(xin)(xin)(xin)(xin)是否同時溶(rong)(rong)(rong)解(jie)(jie)(jie)(jie),可(ke)以將它們的(de)(de)(de)(de)電(dian)位-pH圖重(zhong)疊后(hou)預測。        

 而(er)防止黃(huang)銅脫(tuo)(tuo)鋅腐(fu)(fu)蝕的方法(fa)，主要可(ke)以從(cong)冶金方面入手,其(qi)次也(ye)可(ke)從(cong)改善(shan)環(huan)(huan)境(jing)方面考慮。改善(shan)腐(fu)(fu)蝕環(huan)(huan)境(jing)，則可(ke)以采用陰極保護、添加緩蝕劑、降低介質浸(jin)蝕性等,不過由于受工況條(tiao)件的限制,并(bing)不能(neng)完全抑(yi)制黃(huang)銅的脫(tuo)(tuo)鋅。根治的方法(fa)，則是通過冶金化方法(fa)提(ti)高黃(huang)銅自身的抗脫(tuo)(tuo)鋅能(neng)力,這才(cai)是杜(du)絕(jue)黃(huang)銅脫(tuo)(tuo)鋅腐(fu)(fu)蝕的發生絕(jue)對好(hao)方法(fa)。