環(huan)境(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)是(shi)(shi)考驗(yan)(yan)(yan)(yan)受試(shi)(shi)(shi)產(chan)(chan)(chan)(chan)品(pin)質量特(te)性的(de)(de)一項(xiang)重要手段，因此，開(kai)(kai)展(zhan)環(huan)境(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)已經成(cheng)為(wei)涂層等(deng)高(gao)分子材料的(de)(de)硬性要求(qiu)，在(zai)(zai)產(chan)(chan)(chan)(chan)品(pin)的(de)(de)設計定(ding)型、批生(sheng)產(chan)(chan)(chan)(chan)、驗(yan)(yan)(yan)(yan)收等(deng)階(jie)段必(bi)須通過(guo)(guo)實(shi)驗(yan)(yan)(yan)(yan)室或外場試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)來驗(yan)(yan)(yan)(yan)證產(chan)(chan)(chan)(chan)品(pin)是(shi)(shi)否達到(dao)了技(ji)術要求(qiu)。涂料或涂層常見的(de)(de)環(huan)境(jing)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)有耐溫(wen)(wen)(wen)變、低溫(wen)(wen)(wen)成(cheng)膜性、高(gao)溫(wen)(wen)(wen)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)、低溫(wen)(wen)(wen)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)、濕(shi)熱試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)等(deng)項(xiang)目，需(xu)(xu)要進行多項(xiang)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)。由(you)于周期(qi)長(chang)，成(cheng)本(ben)高(gao)，涉及(ji)范圍廣等(deng)因素(su)，如(ru)果試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)過(guo)(guo)程(cheng)中發生(sheng)問(wen)題，會造成(cheng)較為(wei)嚴重的(de)(de)影響，如(ru)由(you)于試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)實(shi)施(shi)錯誤造成(cheng)受試(shi)(shi)(shi)產(chan)(chan)(chan)(chan)品(pin)故(gu)障,特(te)殊情(qing)況下需(xu)(xu)要重新生(sheng)產(chan)(chan)(chan)(chan)產(chan)(chan)(chan)(chan)品(pin)重新開(kai)(kai)展(zhan)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)；如(ru)產(chan)(chan)(chan)(chan)品(pin)在(zai)(zai)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)過(guo)(guo)程(cheng)中，試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)設備發生(sheng)過(guo)(guo)程(cheng)，已經開(kai)(kai)展(zhan)的(de)(de)試(shi)(shi)(shi)驗(yan)(yan)(yan)(yan)是(shi)(shi)否有效(xiao)需(xu)(xu)要論證是(shi)(shi)否有效(xiao)，如(ru)無效(xiao)也需(xu)(xu)要重新開(kai)(kai)展(zhan)。
基于(yu)氣(qi)候環境(jing)試驗過程中問題(ti)的影響較大，小編梳(shu)理了(le)一(yi)些可能會碰見(jian)的問題(ti)，今天帶大家先了(le)解其一(yi)，凝露問題(ti)。
在(zai)開展低溫(wen)、溫(wen)度(du)循環(huan)等環(huan)境試(shi)(shi)驗(yan)時，在(zai)升降溫(wen)過程中(zhong)(zhong)，由于(yu)(yu)受(shou)試(shi)(shi)產(chan)品(pin)與(yu)試(shi)(shi)驗(yan)箱內空(kong)氣(qi)相(xiang)比，存在(zai)一(yi)定的熱慣(guan)性，受(shou)試(shi)(shi)產(chan)品(pin)的溫(wen)度(du)會(hui)滯后于(yu)(yu)周圍空(kong)氣(qi)溫(wen)度(du)。如果(guo)(guo)(guo)受(shou)試(shi)(shi)產(chan)品(pin)表面(mian)(mian)(mian)的溫(wen)度(du)低于(yu)(yu)周圍空(kong)氣(qi)的露(lu)點溫(wen)度(du)，空(kong)氣(qi)中(zhong)(zhong)的水(shui)分就會(hui)在(zai)受(shou)試(shi)(shi)產(chan)品(pin)表面(mian)(mian)(mian)凝(ning)結，形(xing)成凝(ning)露(lu)。凝(ning)露(lu)現象形(xing)成的水(shui)分會(hui)通(tong)過腐(fu)蝕(shi)或電化學反應等對受(shou)試(shi)(shi)產(chan)品(pin)表面(mian)(mian)(mian)造成不良后果(guo)(guo)(guo)，尤其是涂(tu)覆在(zai)金屬(shu)基材的樣品(pin)，從而影響測試(shi)(shi)結果(guo)(guo)(guo)。
那么其(qi)所形成的原因是什么？
試(shi)驗(yan)箱空(kong)氣(qi)處(chu)理(li)單(dan)元中分布有蒸發器(qi)(qi)、空(kong)氣(qi)循環裝(zhuang)置、電加熱器(qi)(qi)、除濕蒸發器(qi)(qi)等，為保(bao)證工(gong)作(zuo)(zuo)室(shi)內(nei)溫(wen)(wen)度滿足試(shi)驗(yan)要求，蒸發器(qi)(qi)溫(wen)(wen)度會(hui)低于工(gong)作(zuo)(zuo)室(shi)內(nei)空(kong)氣(qi)溫(wen)(wen)度。試(shi)驗(yan)過(guo)程中蒸發器(qi)(qi)由(you)于持續低溫(wen)(wen)會(hui)結霜(shuang)，在低溫(wen)(wen)保(bao)持結束(shu)后升至(zhi)高溫(wen)(wen)或升至(zhi)常溫(wen)(wen)的過(guo)程中，霜(shuang)會(hui)變(bian)成(cheng)水，水會(hui)通(tong)過(guo)空(kong)氣(qi)處(chu)理(li)單(dan)元底(di)部的泄水孔流出試(shi)驗(yan)箱，但由(you)于工(gong)作(zuo)(zuo)室(shi)底(di)部結構原因(yin)，會(hui)存在部分水分無法通(tong)過(guo)泄水孔流出，會(hui)氣(qi)化為水蒸氣(qi)進入(ru)到(dao)試(shi)驗(yan)箱內(nei)。
為滿(man)足受試產品測試需求(qiu)，試驗(yan)箱(xiang)均留有測試孔，通(tong)(tong)過測試電(dian)纜后，用(yong)棉紗堵洞來(lai)封堵。在(zai)高低(di)溫(wen)(wen)試驗(yan)時(shi)，整個試驗(yan)箱(xiang)相當于一個密(mi)封而不氣(qi)密(mi)的腔體，會發生呼吸效應。試驗(yan)箱(xiang)進行低(di)溫(wen)(wen)試驗(yan)時(shi)，試驗(yan)箱(xiang)內空氣(qi)溫(wen)(wen)度降低(di)，壓(ya)力隨之降低(di)，外界濕度含量較大的空氣(qi)會通(tong)(tong)過密(mi)封而不氣(qi)密(mi)的縫隙進入(ru)試驗(yan)箱(xiang)內，在(zai)蒸發器上結(jie)霜。
本文出自：南京環科試(shi)驗(yan)設備(bei)有限(xian)公司(si)，轉載請注明(ming)出處，謝(xie)謝(xie)！
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