任春华,周治顺,计宏伟,等.X80管线钢中微观组织非均匀性对残余应力影响的实验研究[J].精密成形工程,2023,15(8):106-112.
REN Chun-hua,ZHOU Zhi-shun,JI Hong-wei,et al.Experimental Study on the Effect of Microstructure Inhomogeneity on Residual Stress in X80 Pipeline Steel[J].Journal of Netshape Forming Engineering,2023,15(8):106-112. |
| X80管线钢中微观组织非均匀性对残余应力影响的实验研究 |
| Experimental Study on the Effect of Microstructure Inhomogeneity on Residual Stress in X80 Pipeline Steel |
| 投稿时间：2023-05-11 |
| DOI：10.3969/j.issn.1674-6457.2023.08.013 |
| 中文关键词: X80管线钢 微观残余应力 聚焦离子束技术 数字图像相关方法 应变 |
| 英文关键词: X80 pipeline steel microscopic residual stress Focused Ion Beam (FIB) technique digital image correlation method strain |
| 基金项目:天津市自然科学基金(19JCQNJC03700);国家自然科学基金(11502166);2022年天津市研究生科研创新项目(2022SKYZ163) |
|
| 摘要点击次数: 948 |
| 全文下载次数: 445 |
| 中文摘要: |
| 目的 从微纳尺度研究X80管线钢微观组织的不均匀性对残余应力分布及释放过程的影响。方法 为了突出微观组织的非均匀特征，将X80管线钢升温到固溶温度(1 200 ℃)后随炉冷却，得到由大量多边形铁素体(PF)和退化珠光体(DP)构成的显微组织。以腐蚀后的自然形貌为散斑模型，采用聚焦离子束技术在不同微观组织内部进行环芯槽的铣削加工，并获取芯柱表面的变形图像，最后通过数字图像相关方法计算芯柱表面的应变演化。同时，利用纳米压痕技术测试不同区域的弹性模量，结合弹性理论计算分析不同组织内部的微观残余应力。结果 微观结构的不均匀性直接影响了残余应力的分布及释放路径。DP组织中的von Mises平均应变约是PF区域的2倍，残余应力主要存在于作为软质相的铁素体基底中。纳米压痕实验结果表明，DP中弹性模量的浮动比PF的更加剧烈。不同铣削深度下的残余应力呈现出非线性特征。当铣削深度达到1.1 μm时，PF和DP区域松弛释放的残余应力分别为232.6 MPa和385.2 MPa。结论 在微观尺度上，不同组织内的残余应力状态存在差异。微观组织在碳化物、结构形貌等方面的非均匀性将引起表面残余应力的梯度分布。 |
| 英文摘要: |
| The work aims to study the effect of X80 pipeline steel microstructure inhomogeneity on the residual stress distribution and release process from the micro-nano scale.Firstly, in order to highlight the inhomogeneity characteristics of microstructure, the X80 pipeline steel was heated up to the solidus temperature of 1 200 ℃ and then slowly cooled under furnace cooling to obtain the microstructure composed of a large amount of Polygonal Ferrite (PF) and Degenerated Pearlite (DP). With the natural morphology as the speckle model, the Focused Ion Beam (FIB) technique was employed to mill ring-core grooves inside different microstructures. Deformation images of the core surface were obtained. Finally, the strain evolution on the core surface was calculated by digital image correlation (DIC) method. Simultaneously, nanoindentation technique was employed to measure the elastic modulus of different areas. Combined with the results with elastic theory, the micro-scale residual stresses within different microstructures were calculated and analyzed. The inhomogeneity of microstructure directly affected the distribution and release path of residual stress. The von Mises strain in DP was about twice that of the PF area. Most of the residual stress in the DP structure existed in the ferrite matrix. The results of nanoindentation experiment showed that the fluctuation of elastic modulus in DP was more severe than that in PF. The residual stress at different milling depths exhibited nonlinear characteristics. When the milling depth reached 1.1 μm, the released residual stresses in the PF and DP areas were 232.6 MPa and 385.2 MPa, respectively. At the microscopic scale, the state of residual stress varies in different metallographic structures. The inhomogeneity of the microstructure in terms of carbides, structural morphology, etc. will cause a gradient distribution of surface residual stress. |
|
查看全文
查看/发表评论 下载PDF阅读器 |
| 关闭 |
渝公网安备 50010702501719号