簡(jian)單介紹鹽霧試(shi)驗箱的試(shi)驗標準

鹽(yan)(yan)霧(wu)(wu)(wu)(wu)試(shi)(shi)(shi)驗(yan)(yan)(yan)是(shi)一(yi)種(zhong)主要利(li)用(yong)(yong)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)試(shi)(shi)(shi)驗(yan)(yan)(yan)設備所創造的(de)人(ren)工模擬(ni)(ni)(ni)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)條件來考(kao)核產品(pin)或(huo)金屬材料耐腐(fu)(fu)(fu)蝕(shi)性(xing)能(neng)的(de)環(huan)(huan)境(jing)(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)。它分為二大(da)類(lei)(lei)(lei)，一(yi)類(lei)(lei)(lei)為天(tian)然(ran)(ran)環(huan)(huan)境(jing)(jing)暴露試(shi)(shi)(shi)驗(yan)(yan)(yan)，另一(yi)類(lei)(lei)(lei)為人(ren)工加(jia)速模擬(ni)(ni)(ni)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)。人(ren)工模擬(ni)(ni)(ni)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)是(shi)利(li)用(yong)(yong)一(yi)種(zhong)具(ju)有一(yi)定容積(ji)空(kong)間的(de)試(shi)(shi)(shi)驗(yan)(yan)(yan)設備——鹽(yan)(yan)霧(wu)(wu)(wu)(wu)試(shi)(shi)(shi)驗(yan)(yan)(yan)箱，在其(qi)容積(ji)空(kong)間內用(yong)(yong)人(ren)工的(de)方(fang)法(fa)，造成鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)來對產品(pin)的(de)耐鹽(yan)(yan)霧(wu)(wu)(wu)(wu)腐(fu)(fu)(fu)蝕(shi)性(xing)能(neng)質量進(jin)行(xing)(xing)考(kao)核。它與天(tian)然(ran)(ran)環(huan)(huan)境(jing)(jing)相(xiang)比，其(qi)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)的(de)氯化物的(de)鹽(yan)(yan)濃度，可(ke)以是(shi)一(yi)般天(tian)然(ran)(ran)環(huan)(huan)境(jing)(jing)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)含(han)量的(de)幾(ji)倍或(huo)幾(ji)十(shi)倍，使(shi)腐(fu)(fu)(fu)蝕(shi)速度大(da)大(da)提高，對產品(pin)進(jin)行(xing)(xing)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)試(shi)(shi)(shi)驗(yan)(yan)(yan)，得(de)出結果的(de)時(shi)間也大(da)大(da)縮短。如在天(tian)然(ran)(ran)暴露環(huan)(huan)境(jing)(jing)下對某產品(pin)樣品(pin)進(jin)行(xing)(xing)試(shi)(shi)(shi)驗(yan)(yan)(yan)，待(dai)其(qi)腐(fu)(fu)(fu)蝕(shi)可(ke)能(neng)要1年，而在人(ren)工模擬(ni)(ni)(ni)鹽(yan)(yan)霧(wu)(wu)(wu)(wu)環(huan)(huan)境(jing)(jing)條件下試(shi)(shi)(shi)驗(yan)(yan)(yan)，只要24小時(shi)，即可(ke)得(de)到(dao)相(xiang)似的(de)結果。
大多(duo)數的(de)(de)(de)腐(fu)(fu)蝕(shi)(shi)發(fa)生(sheng)(sheng)在大氣(qi)環境(jing)中(zhong)(zhong)，大氣(qi)中(zhong)(zhong)含(han)有氧氣(qi)、濕度、溫度變化(hua)(hua)和污染物(wu)等腐(fu)(fu)蝕(shi)(shi)成(cheng)(cheng)分和腐(fu)(fu)蝕(shi)(shi)因素。鹽(yan)(yan)霧(wu)腐(fu)(fu)蝕(shi)(shi)就是一(yi)種常見和有破壞性的(de)(de)(de)大氣(qi)腐(fu)(fu)蝕(shi)(shi)。這里講(jiang)的(de)(de)(de)鹽(yan)(yan)霧(wu)是指氯(lv)化(hua)(hua)物(wu)的(de)(de)(de)大氣(qi)，它的(de)(de)(de)主要腐(fu)(fu)蝕(shi)(shi)成(cheng)(cheng)分是海洋中(zhong)(zhong)的(de)(de)(de)氯(lv)hua物(wu)鹽(yan)(yan)——氯(lv)hua鈉，它主要來源(yuan)于(yu)海洋和內地鹽(yan)(yan)堿地區。鹽(yan)(yan)霧(wu)對金屬(shu)材料(liao)表面(mian)的(de)(de)(de)腐(fu)(fu)蝕(shi)(shi)是由于(yu)含(han)有的(de)(de)(de)氯(lv)離子穿透金屬(shu)表面(mian)的(de)(de)(de)氧化(hua)(hua)層(ceng)和防護層(ceng)與內部金屬(shu)發(fa)生(sheng)(sheng)電化(hua)(hua)學反(fan)應引起的(de)(de)(de)。同(tong)時，氯(lv)離子含(han)有一(yi)定的(de)(de)(de)水合能，易被吸附在金屬(shu)表面(mian)的(de)(de)(de)孔隙、裂(lie)縫排擠并取代氯(lv)化(hua)(hua)層(ceng)中(zhong)(zhong)的(de)(de)(de)氧，把不溶(rong)性的(de)(de)(de)氧化(hua)(hua)物(wu)變成(cheng)(cheng)可溶(rong)性的(de)(de)(de)氯(lv)化(hua)(hua)物(wu)，使鈍(dun)化(hua)(hua)態表面(mian)變成(cheng)(cheng)活潑表面(mian)。造(zao)成(cheng)(cheng)對產品極壞的(de)(de)(de)反(fan)應。