摘要
负热膨胀(Negative thermal expansion, NTE)材料因其具有热缩冷胀的性质,故在调控材料热膨胀系数(Coefficient of thermal expansion, CTE)方面表现出独特的优势,在复合材料和钎焊领域展现出巨大的潜力。目前NTE材料已在航天、生物医学以及电子信息等领域得到了广泛的应用。在制备复合材料时,将NTE材料作为增强相与正热膨胀材料结合,可以有效调节复合材料的热膨胀系数,将其控制在极低或接近零的水平。在金属基复合材料的制备过程中通过添加NTE增强相,以降低金属基复合材料的热膨胀系数,有效地减少了因热膨胀引起的内部应力,从而延长材料的使用寿命。在钎焊领域中,由于异种母材进行钎焊时热膨胀系数差异较大,接头中会产生较大的残余应力,从而严重影响钎焊接头的性能。在复合钎料中引入NTE材料降低其热膨胀系数,进而减小母材与钎缝之间的热失配,从而有效地降低了接头处的残余应力,以达到提高接头力学性能的目的。
Negative thermal expansion(NTE)materials show unique advantages in regulating the coefficient of thermal expansion of materials due to their heat-shrinking and cold-expanding nature,which show great potential in the field of composite materials and brazing.The NTE materials are used to regulate the high coefficient of thermal expansion of metal composite filler,which have been widely used in aerospace,biomedicine,sensors,and electronic information.In the field of composite materials,the combination of NTE and positive thermal expansion material can effectively regulate the coefficient of thermal expansion of composite materials,controlling it at a very low or near-zero level.Some researchers have utilized the property of NTE materials to reduce the coefficient of thermal expansion of metal matrix composites,and reduce the failure problem caused by temperature difference.In the field of brazing,due to the large difference in the coefficient of thermal expansion of dissimilar materials,the large residual stresses will be produced in the brazed joints,which seriously affects the performance of the components.The coefficient of thermal expansion of metal composite filler by introducing negative expansion materials,reducing the difference of the coefficient of thermal expansion between the base material and brazing seam.Therefore,the NTE materials effectively reduces the residual stresses of the brazed joints,and achieves the purpose of improving the mechanical properties of the brazed joints.
作者
顾磊
王鹏程
闫耀天
陈海燕
李文亚
GU Lei;WANG Pengcheng;YAN Yaotian;CHEN Haiyan;LI Wenya(State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi'an 710072;State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Harbin 150001)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2024年第22期1-20,共20页
Journal of Mechanical Engineering
基金
国家重点研发计划(2022YFB3402200)
国家自然科学基金(52374402)
中国博士后科学基金(2023TQ0271,2023M742831)
国家科技重大专项(J2022-VII-0003-0045)
宁波市首批重大科技攻关(2022Z109)
广东省基础与应用基础研究基金(2023A1515111150)资助项目。
关键词
负膨胀材料
钎焊
金属基复合材料
残余应力
热膨胀系数
negative expansion materials
brazing
metal matrix composites
residual stress
coefficient of thermal expansion
