表面技术2025，Vol.54Issue(17)：162-173,12.DOI:10.16490/j.cnki.issn.1001-3660.2025.17.014
热处理对超音速激光沉积CNTs/Cu复合材料微观结构及导热/导电性能的影响
Effect of Heat Treatment on Microstructure and Thermal/Electrical Conductivity of CNTs/Cu Composite Prepared by Supersonic Laser Deposition
摘要
Abstract
This study employed supersonic laser deposition(SLD)technology to fabricate carbon nanotube-reinforced copper(CNTs/Cu)composites to address challenges such as CNTs ablation under high-heat conditions and weak interfacial bonding in low-heat processes.Structural integrity,dispersion of CNTs,and enhanced electrical/thermal conductivity were achieved through optimized deposition and annealing.This article investigated the effects of CNTs content and heat treatment temperature on the microstructure,thermal conductivity,and electrical conductivity of the composites.Prior to fabrication,CNTs were coated with copper to enhance their wettability with the Cu matrix and reduce the density mismatch between the CNTs and the copper bonding phase.CNTs contents were varied(0.05wt.％,0.1wt.％,0.2wt.％,0.3wt.％),and the composite powders were homogenized via low-speed ball milling(200 r/min,30 min).A 1060 aluminum substrate(100 mm× 100 mm× 5 mm)was pretreated by sandblasting and ultrasonic cleaning in anhydrous ethanol.The SLD system,integrated with a laser unit(Laserline LDF6000-100 VGP),cold spray unit(PCS-1000,Plasma Giken),high-pressure nitrogen tank,and robotic arm(STAÜBLI TX200L),was employed to deposit the composite onto the substrate.The dried powder was fed into the system under optimized SLD parameters:laser power 600 W,carrier gas temperature 500 ℃,gas pressure 3 MPa,scanning speed 10 mm/s,and spray distance 30 mm,through a single-pass deposition and layer-by-layer overlapping strategy.Post-deposition annealing was conducted in a vacuum furnace(SG-XL1400)at 300,400,500,and 600 ℃ with a heating rate of 20 K/min,followed by 1 h holding and furnace cooling.Samples were sectioned by wire cutting and mounted with a metallographic mounting press.The cross-sectional surfaces were ground and polished with a grinding/polishing machine,followed by etching with FeCl3 solution.The microstructure of the composite powders and the surface/cross-sectional morphology of the CNTs/Cu bulk composites were characterized by optical microscopy(AXIO Scope A1)and scanning electron microscopy(Zeiss EVO 18).Elemental analysis of localized regions within the CNTs/Cu bulk composites was performed via energy-dispersive spectroscopy(EDS,Bruker Nano Xflash Detector 5010).Electrical resistivity was measured with a resistivity testing system(Partulab RMS-1000C),while thermal conductivity was determined via laser flash analysis(LFA),with all tests conducted at room temperature.The results revealed that SLD-CNTs/Cu composites prepared with 600 W laser assistance exhibited superior interfacial bonding and surface morphology.Under identical post-treatment annealing at 600 ℃,the thermal conductivity of the composites initially increased then decreased with higher CNTs content,while electrical conductivity showed a monotonic decline.The 0.1％CNTs/Cu composite achieved optimal thermal conductivity of 289.568 W/(m·K)after 600 ℃ annealing,approximately 2.43 times that at room temperature.This enhancement primarily resulted from the transition of interfacial bonding mechanisms from mechanical to metallurgical bonding during annealing,which eliminated pore defects at particle interfaces and established continuous heat transfer pathways.The 0.05％CNTs/Cu composite reached peak electrical conductivity(47.7 MS/m)after annealing at 500 ℃,representing 2.29 times its room temperature(25 ℃)value.This improvement was attributed to recrystallization annealing that alleviated lattice distortions caused by plastic deformation of Cu particles,effectively healing interfacial gaps between particles and enabling full contact between CNTs and the Cu matrix.关键词
超音速激光沉积/CNTs/Cu复合材料/CNTs含量/微观特性/导热/导电性能Key words
supersonic laser deposition/CNTs/Cu composite/CNTs content/microstructure/thermal/electrical conductivity分类
矿业与冶金引用本文复制引用
李波,姚建华,姜家涛,邓家科,李镐成,罗准,耿在明,张盼盼,刘少武,张群莉..热处理对超音速激光沉积CNTs/Cu复合材料微观结构及导热/导电性能的影响[J].表面技术,2025,54(17):162-173,12.基金项目
国家重点研发计划课题(2024YFB4609602) （2024YFB4609602）
国家自然科学基金面上项目(52375469) （52375469）
浙江省自然科学基金青年项目(LQN25E050015) （LQN25E050015）
浙江省高层次人才特殊支持计划(2023R5210)Project of National Key R&D Program of China(2024YFB4609602) （2023R5210）
National Natural Science Foundation of China(52375469) （52375469）
Natural Science Foundation of Zhejiang Province(LQN25E050015) （LQN25E050015）
Zhejiang High-Level Talent Special Support Plan(2023R5210) （2023R5210）
