電(dian)(dian)(dian)化(hua)學拋光(guang)時表(biao)面上形成(cheng)一(yi)層薄厚不均的(de)粘(zhan)性薄膜(mo)(mo)，此(ci)薄膜(mo)(mo)具有很高的(de)電(dian)(dian)(dian)阻，可以避免試件過渡(du)腐(fu)蝕。由于試樣凸(tu)起部分的(de)薄膜(mo)(mo)厚度要比凹陷(xian)處薄，以至(zhi)于凸(tu)出部分的(de)薄膜(mo)(mo)對電(dian)(dian)(dian)解液的(de)擴散作(zuo)用(yong)比較。由于該處薄膜(mo)(mo)薄，電(dian)(dian)(dian)流(liu)密度大，電(dian)(dian)(dian)阻也較小，加之對電(dian)(dian)(dian)解液的(de)擴散作(zuo)用(yong)強烈，故能(neng)迅速被電(dian)(dian)(dian)解作(zuo)用(yong)溶解掉，使凸(tu)起部分逐漸平坦，形成(cheng)光(guang)滑的(de)表(biao)面。

以不(bu)銹鋼復合管護(hu)欄作(zuo)為陽極(ji)接直(zhi)流電(dian)(dian)源的正(zheng)極(ji)，用不(bu)銹鋼、鉛等耐電(dian)(dian)解(jie)(jie)液腐蝕的導電(dian)(dian)材(cai)料作(zuo)為陰極(ji)，接直(zhi)流電(dian)(dian)源的負極(ji)。兩者相距一(yi)定距離(li)浸入電(dian)(dian)解(jie)(jie)液中，在一(yi)定電(dian)(dian)壓、溫度和電(dian)(dian)流密度下，通電(dian)(dian)一(yi)定的時間(jian)，表(biao)面上的微小(xiao)凸起部分便首先溶解(jie)(jie)，而逐漸變成平滑光亮(liang)(liang)的表(biao)面從(cong)而達到表(biao)面光亮(liang)(liang)度增大的效(xiao)果。江西(xi)宜春橋梁(liang)護(hu)欄

二、化(hua)(hua)學(xue)(xue)(xue)拋(pao)(pao)光(guang)(guang)(guang)在化(hua)(hua)學(xue)(xue)(xue)拋(pao)(pao)光(guang)(guang)(guang)中(zhong)不銹鋼(gang)不銹鋼(gang)復合管護欄表面(mian)的拋(pao)(pao)光(guang)(guang)(guang)是在適當的化(hua)(hua)學(xue)(xue)(xue)拋(pao)(pao)光(guang)(guang)(guang)液中(zhong)經化(hua)(hua)學(xue)(xue)(xue)侵(qin)蝕形(xing)成的。不銹鋼(gang)表面(mian)上微觀凸(tu)起部(bu)分的鹽轉化(hua)(hua)膜(mo)較(jiao)薄(bo)在化(hua)(hua)學(xue)(xue)(xue)拋(pao)(pao)光(guang)(guang)(guang)液中(zhong)的溶解速率比微觀凹下部(bu)分要(yao)大得多，從而逐(zhu)漸被整平而平滑光(guang)(guang)(guang)亮的表面(mian)，達(da)到拋(pao)(pao)光(guang)(guang)(guang)目的。

三、機械拋(pao)(pao)光(guang)(guang)用(yong)拋(pao)(pao)光(guang)(guang)帶、拋(pao)(pao)光(guang)(guang)輪等進(jin)行拋(pao)(pao)光(guang)(guang)，拋(pao)(pao)光(guang)(guang)后(hou)可以表面(mian)粗(cu)糙(cao)度的(de)鏡面(mian)。對于(yu)形狀簡單的(de)零(ling)件(jian)可以用(yong)硬拋(pao)(pao)光(guang)(guang)輪或拋(pao)(pao)光(guang)(guang)帶，形狀復(fu)雜的(de)零(ling)件(jian)用(yong)軟拋(pao)(pao)光(guang)(guang)輪拋(pao)(pao)光(guang)(guang)。機械拋(pao)(pao)光(guang)(guang)對表面(mian)磨(mo)(mo)削量很小，難以拋(pao)(pao)光(guang)(guang)粗(cu)糙(cao)表面(mian)。這時需要預行磨(mo)(mo)光(guang)(guang)，用(yong)磨(mo)(mo)光(guang)(guang)輪、磨(mo)(mo)光(guang)(guang)帶沾磨(mo)(mo)光(guang)(guang)膏(gao)進(jin)行磨(mo)(mo)削，分(fen)粗(cu)磨(mo)(mo)、中磨(mo)(mo)和(he)精磨(mo)(mo)。