酸性环境中高强度低合金钢抗SSC性能及氢渗透机理研究

SSC Resistance Performance and Hydrogen Permeation Mechanism of High Strength Low Alloy Steel in Sour Environment

依据NACE TM 0177-2005标准A法SSC实验结果,结合高强度低合金钢的成分、组织、力学性能分析,研究其抗SSC性能,探讨固溶氢含量、氢渗透速率与高强度低合金钢抗SSC性能的关系。研究结果表明:在加载应力为85%YSmin的条件下,抗酸性C110钢通过了NACE TM 0177-2005标准A法检测,具有良好的抗SSC性能。在NACE TM 0177-2005标准A溶液中,抗酸性C110钢的固溶氢含量及氢的有效扩散系数分别为5.2 m L/100g和3.22×10-7cm2/s,相比于普通P110钢,其非金属夹杂程度较低,固溶氢含量及氢的有效扩散系数较小;抗酸性C110钢的稳态氢扩散电流密度及原子氢晶格扩散系数分别为54.1μA/cm2和9.7×10-7cm2/s,相比于普通P110钢,其稳态氢扩散电流密度及原子氢晶格扩散系数较小。随着溶液p H值降低,酸性增强,抗酸性C110钢的氢晶格扩散系数仅稍微增大,在较低p H值的酸性环境中,相比于普通P110钢,C110钢仍具有良好的抗SSC性能。

The SSC resistance performance of high-strength low alloy steels and the relationship between the SSC resistance performance and the hydrogen content and hydrogen permeation rate of high-strength low alloy steels were studied according to the experimental results of NACE TM 0177-2005 standard method A and the analysis of their chemical composition,microstructure and mechanical properties. The results show that under the loading stress of 85% YSmin,C110 steel passes the NACE TM 0177-2005 standard test,and it possesses a good SSC resistance performance. In NACE TM 0177-2005 standard solution A,the hydrogen content and the atomic hydrogen＇s effective diffusion coefficient of antacid C110 alloy steel are 5. 2 m L /100 g and 3. 22 × 10^-7cm^2/ s separately,which are smaller than those of general P110 alloy steel because of the lower non-metallic inclusions in acid-resistant C110 alloy steel; the steady-state hydrogen diffusion current density and the hydrogen lattice diffusion coefficient of the acid-resistant C110 alloy steel are 54. 1 μA / cm^2 and 9.7 × 10^-7cm^2/ s separately,which are smaller than those of the general P110 alloy steel. With the p H value of solution decreasing（ the acidity of solution increasing）,the atomic hydrogen lattice diffusion coefficient of acid-resistant C110 alloy steel increases only slightly,and compared with P110 alloy steel,C110 alloy steel still possesses better SSC resistance performance in the acidic environment of low p H value.