Room temperature creep deformation and its effect on yielding behaviour of a line pipe steel with discontinuous yielding
Room temperature creep deformation and its effect on yielding behaviour of a line pipe steel with discontinuous yielding
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DOI：
10.1016/s0921-5093(00)01800-1
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发表时间：
2001-03
期刊：
影响因子：
6.4
通讯作者：
Sheng-Hui Wang;Weixing Chen
中科院分区：
文献类型：
--
作者：
Sheng-Hui Wang;Weixing Chen
研究了X-52管线钢的屈服后蠕变行为及其对室温拉伸行为的影响。由于碳锁定效应，这种钢表现出明显的屈服点，随后是一系列不连续的屈服。虽然在第一次屈服后的再加载过程中通常不会观察到屈服点，但在蠕变变形耗尽后的再加载过程中，在等于较低屈服强度的应力下存在屈服点。蠕变后屈服点的再现与位错锁定效应有关，而不是碳锁定效应。从初始加载到不连续屈服区的蠕变变形既取决于初始加载应变速率，也取决于初始加载应变。较高的加载应变速率导致较高的位错速度和蠕变开始时较多的移动的位错，从而导致较大的蠕变变形。初始加载应变越小，蠕变变形越大，但包括初始加载应变和后续蠕变应变的总应变对初始加载应变不敏感。
A study was conducted to understand post-yield creep behaviour and its effect on the subsequent tensile behaviour of X-52 line pipe steel at room temperature. As a result of the carbon-locking effect, this steel exhibits a distinct yield point followed by a range of discontinuous yielding. Although normally not observed during re-loading after the first yielding, there was a yield point during re-loading following the exhaustion of creep deformation at a stress equal to the lower yield strength. The re-appearance of the yield point after creep deformation is related to the dislocation locking effect, rather than a carbon locking effect. The creep deformation following the initial loading to the region of discontinuous yielding is dependent on both the initial loading strain rate and the initial loading strain. Higher loading strain rate results in a higher dislocation velocity and a larger number of mobile dislocations at the start of creep, causing larger creep deformation. Smaller initial loading strain causes more creep deformation, but the total strain including the initial loading strain and the subsequent creep strain is insensitive to the initial loading strain.