摘要
采用激光熔覆技术在7075铝合金表面制备了Ti/TiBCN复合涂层,研究了工艺参数对复合涂层的微观组织及性能的影响。利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)研究了Ti/TiBCN复合涂层的相组成和微观组织;利用显微维氏硬度计和往复摩擦磨损试验机研究了Ti/TiBCN涂层的性能。结果表明:当激光功率1 000 W,扫描速度3 mm/s,送粉率300 mg/min时,Ti/TiBCN复合涂层质量最好。涂层上部由树枝晶和部分胞状晶组成,涂层中部为等轴晶,涂层下部呈现球形的TiBCN颗粒。与铝合金基体相比,涂层的平均硬度为519.4 HV0.2,是基体(~120 HV0.2)的4.3倍;涂层的平均摩擦因数为0.208,约是基体(0.442)的1/2;涂层磨损损失量为2.7 mg,约是基体(8.2 mg)的1/3。
Ti/TiBCN composite coating was fabricated on the 7075 aluminum alloy surface by laser cladding technology. The influence of process parameters on the microstructure and properties of the composite coating was studied. The phase composition, microstructure, micro-hardness and wear resistance of the composite coatings were studied by a X-ray diffractometer（XRD）, a scanning electron microscope（SEM）, a Vickers micro-hardness tester and straight-line-reciprocating dry sliding wear tester, respectively. Results show that the Optimal process parameters are as laser power 1 000 W, scanning speed 3 mm/s and the powder feeding rate 300 mg/min. The top, middle and bottom of the coating are consists of dendrites and cellularn crystals, equiaxed crystal and spherical TiBCN particles, respectively. The average hardness of the coating is519.4 HV0.2, which is about 4.3 times higher than that of the substrate（-120 HV）. The average friction coefficient of the coating is 0.208, which is about half of the substrate（0.442）. The mass loss of coating is 2.7 mg, which is about one third of the substrate（8.2 mg）.
作者
张鹏飞
李玉新
李亮
苏科强
张宏建
尉利强
赵占勇
ZHANG Peng-fei;LI Yu-xin;LI Liang;SU Ke-qiang;ZHANG Hong-jian;YU Li-qiang;ZHAO Zhan-yong(College of Materials Science and Engineering, North University of China, Taiyuan 030051)
出处
《中国表面工程》
EI
CAS
CSCD
北大核心
2018年第2期159-164,共6页
China Surface Engineering
基金
国家自然科学基金(51604246)
山西省科技攻关项目(2015031011-2
201603D121002-2)
山西省高等学校科技创新项目(2015104)~~
关键词
铝合金
激光熔覆
微观组织
显微硬度
磨损
aluminum alloy
laser cladding
microstructure
microhardness
wear
