【摘要】：采用慢應變速率拉伸(SSRT)和高溫電化學相結(jié)合的方法,研究了外加電位對321-52M-690異種金屬焊接接頭在含Cl-高溫高壓水中應力腐蝕開裂(SCC)傾向的影響規(guī)律。結(jié)果表明,在300℃、50ppm Cl-環(huán)境下,焊接接頭的SCC敏感性隨電極電位(-700~+100mV)的升高而增大,且存在一個介于0~+50mV(vs.SHE)之間的臨界電位Ecrit。當電極電位低于Ecrit時,焊接接頭的SCC敏感性較小,SCC敏感性指數(shù)ISSRT基本在40%左右,斷裂形式為外力主導的塑性開裂;當電極電位高于Ecrit時,ISSRT急劇增加至70%以上,斷裂形式為腐蝕主導的脆性開裂。試樣斷裂位置均位于硬度最低的321母材處,表明在321/690異種金屬焊接接頭中321母材對SCC最為敏感,故進一步探討了321不銹鋼的應力腐蝕開裂行為和機理。
[Abstract]:The effect of applied potential on the stress corrosion cracking (SCC) tendency of 321-52M-690 dissimilar metal welded joints in high temperature and high pressure water containing Cl- was studied by means of slow strain rate tensile (SSRT) and high temperature electrochemical method. The results show that the SCC sensitivity of welded joints increases with the increase of electrode potential (-700 ~ 100mV) at 300 鈩，

本文編號：2235056