Fe-Cr-Ni合金碱性SCC的电化学研究  

INVESTIGATION ON CAUSTIC SCC OF Fe-Cr-Ni ALLOY IN TERMS OF ELECTROCHEMISTRY

作　　者：黄春波[1] 吕战鹏[1] 杨武[1] 

机构地区：[1]上海材料研究所,上海200437

出　　处：《腐蚀科学与防护技术》2004年第2期67-69,100,共4页Corrosion Science and Protection Technology

基　　金：国家重点基础研究专项经费 (G19990 65 0 );国家科技部科研院所社会公益研究专项资金;上海市青年科技启明星项目 (0 0QE14 0 2 1)

摘　　要：采用控制电位下恒变形C形环试样试验研究了Fe -Cr-Ni合金 (80 0M )在含硫代硫酸钠杂质的热浓碱溶液中的应力腐蚀破裂 (SCC)行为 ,测量了C形环试样恒电位极化时的稳定溶解电流密度ist(稳定溶解速率 ) .用电化学方法研究了腐蚀形貌与电位和 ist的相互关系 ,发现ist随电位的变化呈单调增加趋势 ,ist为 0 6 8mA/cm2 ～ 1 6 2mA/cm2 ,对应电位ESCE=- 30mV～ 4 0mV ,C形环试样发生碱性SCC ;当电位和ist为其它值时 ,发生全面腐蚀 (含晶间腐蚀 ) .Stress corrosion cracking (SCC) behaviors of Fe-Cr-Ni alloy (alloy 800M) in hot concentrated caustic solution were investigated by means of tests of C-ring specimens under controlled potentials.The steady dissolution current densities (i st) of alloy 800M at different potentials were measured.Then the relation between corrosion modes and the potentials and i st were analyzed in terms of electrochemistry.The value of i st increased simply with increasing potential.When the value of i st was 0.68 mA/cm 2～1.62 mA/cm 2,corresponding to potential -30 mV/SCE～40 mV/SCE,caustic SCC occurred.General corrosion (GC) including intergranular attack (IGA) occurred when the potential and i st were other than the values of the above ranges.

关 键 词：稳定溶解电流密度 碱性SCC 电化学 FE-CR-NI合金 应力腐蚀破裂 

分 类 号：TG172.9[金属学及工艺—金属表面处理]