深冷保温时间对三维正交Cf/Al复合材料显微组织与力学性能的影响  

Effects of Cryogenic Holding Time on Microstructure and Mechanical Properties of 3D Orthogonal C_f/Al Composites

作　　者：梁祥 徐志锋 余欢 蔡长春 王振军 单嘉立 Liang Xiang;Xu Zhifeng;Yu Huan;Cai Changchun;Wang Zhenjun;Shan Jiali(National Defense Key Discipline Laboratory of Light Alloy Processing Science and Technology,Nanchang Hangkong University)

机构地区：[1]南昌航空大学轻合金加工科学与技术国防重点学科实验室,南昌330063

出　　处：《特种铸造及有色合金》2021年第1期55-59,共5页Special Casting & Nonferrous Alloys

基　　金：国家自然科学基金资助项目(51765045)。

摘　　要：采用真空气压浸渗法制备了纤维体积分数为50%的三维正交Cf/Al复合材料,主要研究了深冷保温时间对复合材料残余应力、致密度、组织及力学性能的影响,并分析了其影响机理。结果表明,深冷处理改善了三维正交Cf/Al复合材料的显微组织,提高了其致密度,且对三维正交Cf/Al复合材料的残余应力、力学性能有显著的影响。经过深冷处理后,三维正交Cf/Al复合材料的残余应力降低,且随深冷保温时间的增加,残余应力值不断降低。而且深冷处理显著提高了三维正交Cf/Al复合材料的抗拉强度和弹性模量,经36h深冷处理的三维正交Cf/Al复合材料的抗拉强度和弹性模量达到841.33 MPa、132.19GPa,较铸态下的738.85 MPa、105.80GPa分别提高了13.9%、24.9%。经过深冷处理后,显微组织的改善及残余应力的释放是三维正交Cf/Al复合材料力学性能提高的主要原因。The effects of different cryogenic holding times(12、24、36、48 h)were mainly investigated on the residual stress,density,microstructure and mechanical properties of 3D orthorhombic C_f/Al composites with a fiber volume fraction of 50% prepared by vacuum infiltration,and the influence mechanism was analyzed.The results indicate that cryogenic treatment can improve the microstructure and density of 3D orthorhombic C_f/Al composites,which also has a significant effect on the residual stress and mechanical properties.After cryogenic treatment,the residual stress of 3D orthorhombic C_f/Al composites is decreased,and it is decreased continuously with the increase of the cryogenic holding time.The cryogenic treatment can significantly enhance the tensile strength and elastic modulus of the 3D orthorhombic C_f/Al composites,which can reach maximum value of 841.33 MPa and 132.19 GPa after 36 h,and increased by 13.9%、24.9%compared with those in the as-cast state,respectively.Besides,the microstructure improvement and the residual stress release are the main reasons for enhancing mechanical properties of 3D orthogonal C_f/Al composites.

关 键 词：真空气压浸渗 三维正交Cf/Al复合材料 深冷处理 残余应力 

分 类 号：TB333.12[一般工业技术—材料科学与工程]