应变强化奥氏体不锈钢压力容器的强化工艺和设计研究

发布时间：2018-04-19 09:12

本文选题：奥氏体不锈钢 + 压力容器　；参考：《中国石油大学》2011年硕士论文

【摘要】：本文在国家科技部“十一五”“863”计划先进制造技术领域重点项目《极端条件下重大承压设备的设计、制造与维护》(2009AA044801)的支持下,在参阅大量国内外文献及标准的基础上,针对国产0Cr18Ni9奥氏体不锈钢,通过试验研究和理论分析,研究了应变强化工艺对宏观力学性能影响规律;深入研究应变硬化行为,并对其本构关系建立数学模型;定性分析应变强化过程材料内部组织演变过程;定量分析应变强化过程材料内部物相演变规律;对应变强化奥氏体不锈钢压力容器设计方面初步设计研究。本文得到了如下结论: ⑴.随着变形量增加,强度指标大幅提高,而塑性、韧性指标相应降低,即使经过12%变形量的预强化,材料仍有相当好的塑性及韧性储备;准静态下,随着变形速率的加快,材料各项指标变化略微,变形速率对其宏观力学性能影响并不大。 ⑵.随着变形量增加,材料的应变硬化能力逐渐减弱;而准静态下,强化过程中形变速率对其应变硬化能力影响甚微。 ⑶.强化过程阶段,随着应变速率的加快,强度越高,应变速率敏感性更强。 ⑷.随着变形量增加,材料的显微硬度逐渐上升;上升趋势与屈服强度随变形量上升趋势相近。 ⑸.随着变形量增加,材料内部滑移线明显聚集,并随之产生一定量的形变孪晶及少量应变诱发马氏体;准静态下,随着形变速率的加快,内部组织形貌相似,滑移线略微密集。 ⑹.随着变形量增加,奥氏体γ相含量呈线性下降趋势,应变诱发马氏体α′相含量逐渐上升,应变诱发马氏体ε相含量呈先上升后下降趋势,小应变阶段,相变主要由γ相向α′、ε相共同转变,大应变阶段,部分ε相向α′相转变;准静态下,随着变形速率的加快,应变诱发马氏体含量逐渐降低。
[Abstract]:In this paper, the State Ministry of science and technology "in 11th Five-Year" and "863" plan advanced manufacturing technology key project "under extreme conditions of major pressure equipment design, manufacturing and maintenance > (2009AA044801) support, on the base of a large number of domestic and foreign literatures and standards, for domestic 0Cr18Ni9 Austenitic stainless steel, through experiment and theoretical analysis. Study on the process law of strain hardening effect on macroscopic mechanical properties; study the strain hardening behavior and the constitutive relation model; qualitative analysis of strain hardening process inside the material microstructure evolution process; quantitative analysis of internal strain hardening material phase evolution rule; strain the preliminary design of the strengthening design of austenitic stainless steel pressure vessel the following conclusions are drawn:
1. With the increasing of strain intensity index is greatly improved, and the plasticity, toughness index decreased, even after 12% deformation of the pre reinforcement material still has the plasticity and toughness of very good reserve; quasi static, with the deformation rate, changes of the material slightly, the deformation rate of the macro the mechanical properties of the impact is not big.
2. With the increase of deformation, strain hardening ability of materials decreased gradually; while under quasi-static strain rate has little effect on the strain hardening ability in the hardening process.
3. During the process of strengthening with increasing strain rate, the higher the strength, strain rate sensitivity is stronger.
4. With the increase of deformation, the hardness of materials increased gradually rising trend; and the yield strength increased with the deformation tendency is similar.
The. With the increase of deformation, the slip line material internal obvious aggregation, and produces a certain amount of deformation twins and a small amount of strain induced martensite; quasi-static strain rate, with the speeding up of the internal morphology is similar to that of the slip line slightly denser.
6. With the increase of deformation of austenite phase content decreases linearly, strain induced martensite alpha 'phase content increased gradually, strain induced martensite phase content was first increased and then decreased, small strain phase transformation mainly by gamma to alpha epsilon', phase transformation, large strain stage, part e to alpha 'phase transition; quasi static, with the deformation rate, strain induced martensite content decreased gradually.

【学位授予单位】：中国石油大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH49

【引证文献】