摘要
利用激光表面合金化和宽带激光熔覆工艺在铜基体表面制备出由Cu-Ni合金化层和NiCrBSi熔覆层组成的梯度涂层。用X射线衍射仪、扫描电镜、能谱仪及显微硬度计,系统分析合金化层与熔覆层的物相构成、显微组织及硬度。结果表明:合金化层与铜基体之间的界面呈"锯齿状",在合金化层近基材底部是一种不规则的层状结构;在合金化层中,Ni、Cu元素发生充分互溶,使合金化层的热导率降低至Cu基体的1/9,有效提升铜表面NiCrBSi熔覆层的成形能力;同时,NiCrBSi熔覆层组织致密,其强化相由γ-Ni、Cr B、M_(23)C_6及Ni_3Si构成,显微硬度明显提高,平均值达到400HV,是铜基体硬度的5倍。从铜基体到NiCrBSi熔覆层,显微硬度呈梯度增加,涂层具有里韧外硬的特征。
A gradient coating consisting of Cu-Ni alloying layer and NiCrBSi cladding layer was prepared on copper by lasersurface alloying and wide-band laser cladding. The X-ray diffraction（XRD）, scanning electron microscopy（SEM）equipped withenergy disperse spectroscopy （EDS） and microhardness tester were used to investigate the phase, microstructure and hardness.The results show that the interface between the copper and alloying layer is ＂serration＂, and the bottom of the alloying layer is akind of irregular laminated structure. The Ni and Cu elements are fully miscible in the alloying layer so that the thermalconductivity of the alloying layer is reduced to one ninth of the copper substrate. The microstructure of NiCrBSi cladding layer iscompact and the phases are composed of γ-Ni, CrB, M23C6, and Ni3Si. The average microhardness of the cladding layer reaches400HV, which is 5 times as high as that of copper substrate. The microhardness of the coating increases in gradient fromsubstrate to NiCrBSi cladding layer. The coating has the characteristics of hard surface and tough at core.
作者
赵健
刘光
马冰
郑子云
贾利
崔烺
徐建江
ZHAO Jian, LIU Guang, MA Bing, ZHENG Ziyun, JIA Li, CUI Lang, XU Jianjiang2(1.Ningbo Branch of Chinese Academy of Ordnance Science, Ningbo 315103, China; 2.Saikesi Hydraulic Science and Technology Co., Ltd, Ningbo 315021, Chin)
出处
《兵器材料科学与工程》
CAS
CSCD
北大核心
2018年第2期53-57,共5页
Ordnance Material Science and Engineering
基金
宁波市科技创新团队项目(2014B82001)
宁波市重大技术专项(2016B10027)
关键词
铜
激光合金化
激光熔覆
镍基梯度涂层
显微硬度
copper
laser alloying
laser cladding
Ni-based gradient coating
microhardness
