C_(f)/Mg复合材料异形薄板件真空吸渗挤压成形及其刚度研究  

Preparation and Stiffness Property of C_(f)/Mg Composite Special-shaped Thin Parts Fabricated by Liquid-solid Extrusion Following Vacuum Pressure Infiltration

作　　者：陈宝林 卢竹青 周计明[1,3] 鞠录岩 齐乐华[1,3] CHEN Baolin;LU Zhuqing;ZHOU Jiming;JU Luyan;QI Lehua(School of Mechanical Engineering,Northwestern Polytechnical University,Xi'an 710072;Western Superconducting Technologies Co.,Ltd.,Xi'an 710018;Shaanxi Key Laboratory of Fiber Reinforced Light Composite Materials,Xi'an 710072)

机构地区：[1]西北工业大学机电学院,西安710072 [2]西部超导材料科技股份有限公司,西安710018 [3]陕西省纤维增强轻质复合材料重点实验室,西安710072

出　　处：《机械工程学报》2025年第4期107-115,共9页Journal of Mechanical Engineering

基　　金：国家自然科学基金(52231004,52471164,52475405);陕西省技术创新引导专项(基金)(2020CGHJ-011)资助项目。

摘　　要：碳纤维增强镁基(C_(f)/Mg)复合材料因轻质、高比强度、高比模量及良好的尺寸稳定性等特性,在航空航天、武器装备和轨道交通等领域有着重要应用前景。但因碳纤维与镁合金润湿性差、界面处易高温反应,特别是薄板件成形时受薄壁、复杂形状特征影响,易出现充型不完整、变截面处镁液浸渗不均匀,制备难度大,严重制约C_(f)/Mg材料的实际应用。真空吸渗挤压工艺是利用抽真空使熔融金属液浸渗至预制体中,随即在机械压力下充分浸渗,并在其处于液固态时施加高压使其进一步凝固补缩以实现致密化,从而提高制件整体性能。以某型导弹电子器件安装板研制为例,对其工艺过程、试验参数、样件抗拉性能与整体刚度进行深入研究,结果表明:该工艺可以成形出符合要求的C_(f)/Mg异形薄板件;挤压温度600℃且有循环冷却时,镁液充型完整、浸渗均匀;设计的加载循环冷却系统可有效减缓碳纤维和镁合金之间的界面反应,使复合材料异形薄板件拉伸性能和整体刚度进一步提升,抗拉强度、弹性模量为328 MPa和68 GPa,较未循环冷却件分别提高24%和6%,比相同镁合金样件分别提高139%和79%;经整体承载能力测试,加载700 N时其变形量为0.313 mm,比相同镁合金样件的变形量减小2/3。本研究为C_(f)/Mg复合材料结构件制备和应用奠定了基础。The carbon fiber reinforced magnesium matrix(C_(f)/Mg)composites exhibit light weight,high specific strength and modulus as well as excellent dimensional stability,which means more potential for engineering applications such as in aeronautic/astronautic equipment,light armaments,and railway traffic equipment.Due to the poor wettability and the high-temperature reaction between the carbon fiber and magnesium alloy,especially the forming thin parts with the thin wall and complex shapes,the incomplete filling or the nonuniform infiltration of liquid magnesium at variable cross-section is prone to occur.These challenges increase the difficulty of the preparation,which limits the practical applications of C_(f)/Mg composites.The liquid-solid extrusion following vacuum pressure infiltration mainly includes the following steps.Firstly,the molten metal infiltrates partially into the fiber preform under a vacuum environment.Then,the preform is fully infiltrated by a hydraulic pressure.When the metal solidifies into a liquid-solid state,a high pressure is applied to further restrict the shrinkage and increase the densification.The process can improve the overall performance of composite parts.Taking the preparation of an electronic mounting plate of the missile as a typical example,the process steps,process parameters,tensile properties and integral stiffness of the composite plate are studied in detail.The result shows that the fabricated C_(f)/Mg thin parts can meet the requirements of practical applications.When the extrusion temperature is 600℃and the circulating cooling system is installed,the preform is completely and uniformly infiltrated by the molten magnesium alloy.The detrimental interfacial reaction between the fiber and magnesium alloy is decreased by the designed circulating cooling system,which further improves the mechanical properties of C_(f)/Mg thin parts.The ultimate tensile strength and elastic modulus reach up to 328 MPa and 68 GPa,respectively,which are 24%and 6%higher than those of uncirculated co

关 键 词：镁基复合材料 真空吸渗挤压 碳纤维 异形薄板件 整体刚度 

分 类 号：TB331[一般工业技术—材料科学与工程]