提高压力容器用钢板耐酸性的组织控制和适用钢的特性

Microstructure Control for Improving Sou. Resistance of Pressure Vessel Steel Plates and Their Performance

叙述了对于压力容器用钢材在湿润硫化氢环境下所发生的氢诱发裂纹 (HIC)和硫化物应力腐蚀裂纹 (SSC)的提高抵抗性能技术。根据这个技术生产出到 12 7m m厚 ASTM A5 16 - 70级和 5 0 .8mm厚的 A841级压力容器用钢板 ,已确认具有良好的耐 HIC性能和耐 SSC性能。耐HIC性能由于把 S含量降到非常低和添加 Ca使 ACR值适当 (1～ 3)时则有明显提高。采用潜在起点模型可以说明 SSC的一种特征所示发生形态的 SOHIC机理 ,基体屈服强度的提高和珠光体团等潜在起点的细化和相互间隔的扩大使耐 SOHIC性能提高。控制这种组织 TMCP是最适宜方法 ,采用 TMCP生产 A841级压力容器用钢的组织 ,具有良好的耐 SOHIC性能。

The technologies discussed herein are to advance the resistnace to hydrogen-induced cracking (HIC)and sulfide stress corrosion cracking(SSC)of pressure vessel steels to make them applicable in wet H 2S environmemts. The heavy gauge plates of ASTM A516-70 grade up to 127mm and the A841cl.1 grade of 50.8mm in thickness with high welding perfcrmance have been manufactured in accordance with those technologies. HIC-resistance is remarkably improved by reducing sulfur content and conducting clustering-free shape-control of MnS. the latter of which is carried out with appropriate ACR values(1 to 3)obtained by Ca addition. The unique behavior of the stress oriented(SO)HIC has become comprehensive with the concept of“latent initiation site model”. The model also indicated the efficiency of thermo-mechanical control process(TMCP)for preventing SOHIC and excellent SOHIC prevetive properties have been proved in the developed A841 steel plate of the TMCP type.