采用慢应变速率拉伸试验(SSRT)及断口观测研究了不同显微组织X70钢的应力腐蚀破裂(SCC)敏感性。结果表明:X70钢及其不同热处理后的劣化组织在鹰潭土壤模拟溶液中均具有明显的SCC敏感性;三种组织X70钢的SCC敏感性整体上表现为随外加电位的降低而增大,组织硬化和晶粒过大都能增加材料的SCC敏感性。
The stress corrosion cracking(SCC) susceptibility of X70 steel with three types of microstructure was analyzed by means of slow strain rate testing(SSRT) and fracture surface(SEM) observation.The experimental results illustrated that the steel after different heat treatments had higher SCC susceptibility than the as received steel.With decreasing polarization potential,the SCC susceptibility of the X70 with different kinds of microstructure increased.Both hardening and grain coarsening can increase the SCC susceptibility.