【摘要】 研究了恒定载荷和三种频率的动载荷条件下,经淬火及低温回火的两种低碳马氏体钢在25℃,3.5％NaCl水溶液中的裂纹扩展行为。结果表明载荷频率对低碳马氏体钢腐蚀疲劳裂纹扩展的动力学特征影响很大,特别是在K_max<K_lscc区。作者认为载荷频率的上述影响是因裂纹尖端的应变速率随载荷频率而变化,从而改变了裂纹起始与扩展的热力学条件。更多还原

【Abstract】 The crack growth behavior is investigated for low-carbon martensitic steels quenched and tempered at low temperature, under static loading and cyclic loading with three frequencies in 3.5% NaCl solution at 25℃. The fractorgraphs are examined with SEM. It is shown that there is a considerable influence of loading frequency on crack propagation dynamic characteristics of the steels, particularly in region of K_max<K_1SCC. The authors suggest that this effect is due to the change in the strain rate of crack tip metal thus altering the thermodynamics of crack onset and growth.更多还原