SiCp/Al超低温材料流动行为和本构模型构建  

Cryogenic Flow Behavior of SiCp/Al Composite and Construction of Constitutive Model

作　　者：郭维诚 吴杰 郭淼现 孙启梦 GUO Weicheng;WU Jie;GUO Miaoxian;SUN Qimeng(School of Mechanical Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Dynamic Machinery Institute of Inner Mongolia,Hohhot 010010,China)

机构地区：[1]上海理工大学机械工程学院,上海200093 [2]内蒙动力机械研究所,呼和浩特010010

出　　处：《材料导报》2025年第4期200-207,共8页Materials Reports

基　　金：国家自然科学基金(52105470,52275452)。

摘　　要：碳化硅颗粒增强铝基复合材料(SiCp/Al)由于优异的综合性能在航空航天领域应用广泛,而超低温处理已被证明在材料成形工艺中能进一步提升材料性能,面对愈加苛刻的工业要求,研究SiCp/Al在超低温下的流变特性显得尤为重要。本工作通过电子拉伸试验机对20%SiCp/Al进行了-196℃下准静态拉伸试验,并利用分离式霍普金森压杆装置进行了温度范围-196~20℃、应变率范围1 000~3 000 s^(-1)的动态压缩试验。结果表明,SiCp/Al的应变率强化效应不显著,而超低温对材料的流动应力具有显著的强化效果。结合位错运动、应变硬化与动态再结晶软化分析了材料流动行为的变形机制。综合考虑应变、温度和应变率对材料流变特性影响的耦合效应对所建立的Johnson Cook本构模型进行修正,对比发现,修正Johnson Cook(MJC)模型能够较好地反映材料不同条件下的流动应力,预测误差降低了50%以上。Silicon carbide particle-reinforced aluminum matrix composites(SiCp/Al)are widely used in aerospace field due to the excellent comprehensive performance,and cryogenic treatmenthas been proved to be able to further enhance the material properties in the material forming process.In the face of highly demanding industrial requirements,the study of the rheological properties of SiCp/Al at cryogenic temperatures is particularly important.In this work,the quasi-static tensile test of 20%SiCp/Al at-196℃was carried out with electronic tensile machine.Dynamic compression tests at the temperature range of-196—20℃and the strain rate range of 1000~3000 s^(-1) were carried out with the split Hopkinson pressure bar.The results show that the strain rate strengthening effect of SiCp/Al is not significant,while cryogenic temperature has a great strengthening effect on the flow stress of the material.The deformation mechanism of the flow behavior is analyzed by combining the dislocation movement,strain hardening and dynamic recrystallization softening.The coupling effect of strain,temperature and strain rate on the rheological properties of the material is considered to modify the established Johnson Cook model.It is found that the modified Johnson Cook(MJC)model could properly reflect the flow stress under different conditions,and the prediction error is reduced by more than 50%.

关 键 词：SICP/AL 分离式霍普金森压杆 静动态力学性能 超低温 本构模型 

分 类 号：TG115[金属学及工艺—物理冶金]