摘要
通过SO_2气体加速腐蚀实验,利用环境扫描电镜(XL30-FEG-ESEM)、能谱分析(EDAX)和Fourier红外光谱(FTIR)等分析技术,研究了碳钢Q235在湿热SO_2气氛中的腐蚀行为和锈巢形成机制,结果表明:Q235在不同浓度SO_2中腐蚀速率的变化趋势是不同的,浓度较高时,腐蚀速率随腐蚀时间延长而降低;浓度较低时,腐蚀速率随腐蚀时间延长缓慢增加,提高SO_2浓度对锈层中含硫化合物的形成影响不大,但对锈层中氧化物或氢氯化物形成起到促进作用,实验条件下的腐蚀产物均含有FeSO_4·7H_2O,Fe_2(SO_4)3·9H_2O,γ-FeOOH和无定形的6-FeOOH,当SO_2体积分数大于0.5%时,产物中还出现a-FeOOH.在0.05%SO_2气氛中,Q235表面形成锈巢,锈巢内、外的各种元素含量差异很大。
The initial corrosion behaviors of carbon steel Q235 in the atmosphere with different concentrations of SO2 were investigated by SEM/EDAX and FTIR. The corrosion kinetics results showed the variation of thickness loss of Q235 is related to concentrations of SO2. When the concentration of SO2 was relatively low, the thickness loss increased slowly, and when the concentration of SO2 was relatively high, the thickness loss decreased rapidly. The concentration of SO2 has a little effect on sulfate in the products, but facilitated the formations of oxide or hydrate in the rust layer. In all conditions, the corrosion products included MSO4·7H2O,Fe2（SO4）3·9H2O, γ- FeOOH and amorphous δ -FeOOH, but the concentration of SO2 was enhanced to 0.5% （volume fraction）, α-FeOOH was detected in the corrosion products. In the atmosphere with 0.05%SO2, rust nests appeared in the rust layer and the elements inside and outside the nest were great different, and a probable mechanism was proposed.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第6期729-734,共6页
Acta Metallurgica Sinica
基金
国家自然科学基金项目50499331
国家科技基础条件建设项目2005DKA10400资助
