鹽霧實驗和鹽霧的腐蝕作用：
腐(fu)蝕(shi)是材料或(huo)其性(xing)能在環(huan)境(jing)(jing)的(de)(de)(de)(de)作用下引起的(de)(de)(de)(de)破壞或(huo)變(bian)質。大多數的(de)(de)(de)(de)腐(fu)蝕(shi)發(fa)生(sheng)在大氣環(huan)境(jing)(jing)中(zhong)，大氣中(zhong)含(han)有(you)(you)氧(yang)(yang)氣、濕度、溫度變(bian)化(hua)(hua)和污染物(wu)(wu)等腐(fu)蝕(shi)成(cheng)(cheng)(cheng)分(fen)和腐(fu)蝕(shi)因素。鹽(yan)霧腐(fu)蝕(shi)就是一(yi)種常見和*有(you)(you)破壞性(xing)的(de)(de)(de)(de)大氣腐(fu)蝕(shi)。這里講的(de)(de)(de)(de)鹽(yan)霧是指氯(lv)化(hua)(hua)物(wu)(wu)的(de)(de)(de)(de)大氣，它的(de)(de)(de)(de)主要腐(fu)蝕(shi)成(cheng)(cheng)(cheng)分(fen)是海洋(yang)(yang)中(zhong)的(de)(de)(de)(de)氯(lv)化(hua)(hua)物(wu)(wu)鹽(yan)——氯(lv)化(hua)(hua)鈉，它主要來源于(yu)海洋(yang)(yang)和內地鹽(yan)堿地區(qu)。鹽(yan)霧對金屬材料表(biao)(biao)面的(de)(de)(de)(de)腐(fu)蝕(shi)是由于(yu)含(han)有(you)(you)的(de)(de)(de)(de)氯(lv)離子(zi)(zi)穿透金屬表(biao)(biao)面的(de)(de)(de)(de)氧(yang)(yang)化(hua)(hua)層和防護層與內部金屬發(fa)生(sheng)電化(hua)(hua)學反應(ying)引起的(de)(de)(de)(de)。同(tong)時，氯(lv)離子(zi)(zi)含(han)有(you)(you)一(yi)定的(de)(de)(de)(de)水合能，易被吸附在金屬表(biao)(biao)面的(de)(de)(de)(de)孔隙、裂縫排擠并取代氯(lv)化(hua)(hua)層中(zhong)的(de)(de)(de)(de)氧(yang)(yang)，把不溶性(xing)的(de)(de)(de)(de)氧(yang)(yang)化(hua)(hua)物(wu)(wu)變(bian)成(cheng)(cheng)(cheng)可溶性(xing)的(de)(de)(de)(de)氯(lv)化(hua)(hua)物(wu)(wu)，使鈍化(hua)(hua)態表(biao)(biao)面變(bian)成(cheng)(cheng)(cheng)活(huo)潑表(biao)(biao)面。造成(cheng)(cheng)(cheng)對產品極壞的(de)(de)(de)(de)**反應(ying)。鹽霧(wu)腐蝕試驗(yan)測試機原理分(fen)享

鹽霧試驗及與實際的聯系：
鹽(yan)霧(wu)(wu)試驗(yan)(yan)是一種(zhong)主(zhu)要利(li)用(yong)(yong)鹽(yan)霧(wu)(wu)試驗(yan)(yan)設備所創造的人(ren)工(gong)(gong)(gong)模擬鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)條件來考(kao)核產(chan)品(pin)(pin)或金屬(shu)材料耐(nai)(nai)腐蝕(shi)性(xing)能(neng)的環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)試驗(yan)(yan)。它(ta)分為二大(da)類，一類為天然(ran)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)暴露試驗(yan)(yan)，另(ling)一類為人(ren)工(gong)(gong)(gong)加(jia)速模擬鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)試驗(yan)(yan)。人(ren)工(gong)(gong)(gong)模擬鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)試驗(yan)(yan)是利(li)用(yong)(yong)一種(zhong)具有一定容積空間(jian)的試驗(yan)(yan)設備——鹽(yan)霧(wu)(wu)試驗(yan)(yan)箱，在其(qi)容積空間(jian)內用(yong)(yong)人(ren)工(gong)(gong)(gong)的方(fang)法，造成鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)來對(dui)(dui)產(chan)品(pin)(pin)的耐(nai)(nai)鹽(yan)霧(wu)(wu)腐蝕(shi)性(xing)能(neng)質量進(jin)行考(kao)核。它(ta)與天然(ran)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)相比，其(qi)鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)的氯化物的鹽(yan)濃度，可(ke)以是一般天然(ran)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)鹽(yan)霧(wu)(wu)含量的幾倍或幾十倍，使腐蝕(shi)速度大(da)大(da)提高，對(dui)(dui)產(chan)品(pin)(pin)進(jin)行鹽(yan)霧(wu)(wu)試驗(yan)(yan)，得出結(jie)果的時間(jian)也大(da)大(da)縮短(duan)。如在天然(ran)暴露環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)下對(dui)(dui)某產(chan)品(pin)(pin)樣品(pin)(pin)進(jin)行試驗(yan)(yan)，待其(qi)腐蝕(shi)可(ke)能(neng)要1年(nian)，而在人(ren)工(gong)(gong)(gong)模擬鹽(yan)霧(wu)(wu)環(huan)(huan)(huan)境(jing)(jing)(jing)(jing)(jing)條件下試驗(yan)(yan)，只(zhi)要24小時，即可(ke)得到相似的結(jie)果。

鹽霧(wu)試驗(yan)的分類(lei)：
人工模擬鹽(yan)霧(wu)試(shi)(shi)驗(yan)(yan)(yan)又(you)包括(kuo)中性(xing)鹽(yan)霧(wu)試(shi)(shi)驗(yan)(yan)(yan)、醋酸(suan)鹽(yan)霧(wu)試(shi)(shi)驗(yan)(yan)(yan)、銅(tong)鹽(yan)加速(su)醋酸(suan)鹽(yan)霧(wu)試(shi)(shi)驗(yan)(yan)(yan)、交變鹽(yan)霧(wu)試(shi)(shi)驗(yan)(yan)(yan)。
1.中性(xing)鹽霧試(shi)驗(yan)(NSS試(shi)驗(yan))是出現*早目前(qian)應用領域*廣的一種加速腐(fu)蝕試(shi)驗(yan)方(fang)法。它采用5%的氯化鈉鹽水溶液(ye)(ye)，溶液(ye)(ye)PH值調在(zai)中性(xing)范圍(wei)(6～7)作為噴霧用的溶液(ye)(ye)。試(shi)驗(yan)溫度均取35℃，要求鹽霧的沉(chen)降率(lv)在(zai)1～2ml/80cm2.h之間(jian)。

2.醋酸(suan)(suan)鹽(yan)霧試(shi)驗(ASS試(shi)驗)是(shi)(shi)在(zai)中(zhong)性(xing)鹽(yan)霧試(shi)驗的(de)(de)基礎上發展(zhan)起來的(de)(de)。它是(shi)(shi)在(zai)5%氯(lv)化鈉溶液(ye)中(zhong)加(jia)入一些(xie)冰醋酸(suan)(suan)，使溶液(ye)的(de)(de)PH值降為3左右(you)，溶液(ye)變成(cheng)酸(suan)(suan)性(xing)，*后形成(cheng)的(de)(de)鹽(yan)霧也由(you)中(zhong)性(xing)鹽(yan)霧變成(cheng)酸(suan)(suan)性(xing)。它的(de)(de)腐蝕速(su)度要比NSS試(shi)驗快3倍左右(you)。

3.銅(tong)鹽加(jia)速醋酸鹽霧(wu)試(shi)驗(yan)(yan)(CASS試(shi)驗(yan)(yan))是(shi)國外新近(jin)發展(zhan)起來的一種(zhong)快速鹽霧(wu)腐蝕試(shi)驗(yan)(yan)，試(shi)驗(yan)(yan)溫度為50℃，鹽溶液中加(jia)入少(shao)量銅(tong)鹽—氯化銅(tong)，強烈誘(you)發腐蝕。它(ta)的腐蝕速度大約是(shi)NSS試(shi)驗(yan)(yan)的8倍。

4.交(jiao)變鹽霧(wu)試驗(yan)是一(yi)種綜(zong)合鹽霧(wu)試驗(yan)，它(ta)(ta)實際上是中性(xing)鹽霧(wu)試驗(yan)加恒(heng)定(ding)濕熱試驗(yan)。它(ta)(ta)主要用于空腔型的(de)整(zheng)機(ji)產(chan)品，通(tong)過潮態(tai)環境(jing)的(de)滲透，使(shi)鹽霧(wu)腐蝕不(bu)但(dan)在產(chan)品表面產(chan)生，也在產(chan)品內部產(chan)生。它(ta)(ta)是將(jiang)產(chan)品在鹽霧(wu)和(he)濕熱兩種環境(jing)條(tiao)件(jian)下交(jiao)替轉(zhuan)換，*后考(kao)核整(zheng)機(ji)產(chan)品的(de)電(dian)性(xing)能(neng)(neng)和(he)機(ji)械性(xing)能(neng)(neng)有無變化