Influence of prior cyclic plasticity on creep deformation using crystal plasticity modelling
Influence of prior cyclic plasticity on creep deformation using crystal plasticity modelling
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DOI：
10.1016/j.ijsolstr.2018.01.028
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发表时间：
2018-05
影响因子：
3.6
通讯作者：
T. Erinosho;K. A. Venkata;M. Mostafavi;D. Knowles;C. Truman
中科院分区：
文献类型：
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作者：
T. Erinosho;K. A. Venkata;M. Mostafavi;D. Knowles;C. Truman
本文提出了一种简单而有效的修正晶体塑性框架，它能够模拟塑性和蠕变变形。特别是，所提出的模型是足够通用的捕获复杂的负载历史对多晶体的影响，代表那些经历了工业厂房中的真实的材料。具体而言，该方法的动机是需要在发电行业，以确定是否循环预应变影响随后的蠕变行为的316 H型奥氏体不锈钢相比，非循环预应变的材料。循环预应变广泛存在于工厂中，准确地解释其对相关部件后续变形和完整性的影响至关重要。本文提出的框架以相对简单的方式考虑了位错滑移和攀移的影响。它是校准使用实验测试316 H不锈钢只进行单调塑性和向前蠕变。预测，然后获得相同材料的蠕变响应后，它已受到周期的预应变。的预测与实验结果进行了比较，观察到良好的一致性。结果表明，较慢的蠕变应变积累之前的循环加载归因于在循环预应变过程中开发的材料中的硬化结构。该模型还强调了在反向加载下的硬化的方向性占的重要性。这是假设影响内部应力状态的发展，在晶内水平，这可能会影响随后的蠕变积累。
This paper proposes a simple, yet effective, modified crystal plasticity framework which is capable of modelling plasticity and creep deformation. In particular, the proposed model is sufficiently versatile to capture the effects of complex load histories on polycrystals, representative of those experienced by real materials in industrial plant. Specifically, the methodology was motivated by the need in the power generation industry to determine whether cyclic pre-straining influences the subsequent creep behaviour of type 316H austenitic stainless steel as compared to non-cyclically pre-strained material. Cyclic pre-straining occurs widely in plant and it is of paramount importance to accurately account for its impact on the subsequent deformation and integrity of relevant components.The framework proposed in this paper considers the effects of dislocation glide and climb in a relatively simple manner. It is calibrated using experimental tests on 316H stainless steel subjected solely to monotonic plasticity and forward creep. Predictions are then obtained for the creep response of the same material after it had been subjected to cycles of pre-strain. The predictions are compared to experimental results and good agreement was observed. The results show slower creep strain accumulation following prior cyclic loading attributed to hardening structures developed in the material during the cyclic pre-strain. The model also highlights the importance of accounting for directionality of hardening under reverse loading. This is hypothesized to affect the development of an internal stress state at an intragranular level which is likely to affect subsequent creep accumulation.