文献类型：期刊文献

中文题名：Effect of Laser Power on the Microstructure and Mechanical Properties of TiN/Ti_3Al Composite Coatings on Ti6Al4V

英文题名：Effect of laser power on the microstructure and mechanical properties of TiN/Ti3Al composite coatings on Ti6Al4V

作者：Liu, Zhengdao[1]; Zhang, Xiancheng[1]; Xuan, Fuzhen[1]; Wang, Zhengdong[1]; Tu, Shandong[1]

机构：[1] Key Laboratory of Pressure Systems and Safety of Ministry of Education, East China University of Science and Technology, Shanghai 200237, China

年份：2013

卷号：26

期号：4

起止页码：714

中文期刊名：Chinese Journal of Mechanical Engineering

外文期刊名：Chinese Journal of Mechanical Engineering (English Edition)

收录：CSTPCD;;EI(收录号：20133316623587);Scopus;CSCD:【CSCD2013_2014】；

基金：supported by National Natural Science Foundations of China(Grant Nos. 51175177, 10672058);Shanghai Municipal Leading Academic Discipline Project of China (Grant No. B503)

语种：英文

中文关键词：composite coating; laser nitriding; laser power; microstructure; mechanical properties

外文关键词：Aluminum alloys - Aluminum nitride - Fracture toughness - Ternary alloys - X ray diffraction - Fracture - Scanning electron microscopy - Energy dispersive spectroscopy - Tin - Cracks - Titanium nitride - Turbomachine blades - Composite coatings - Titanium alloys - Elastic moduli - Microhardness - Plasma spraying

摘要：Laser nitriding is one of the effective techniques to improve the surface properties of titanium alloys and has potential application in the life extension of last-stage steam turbine blades. However, cracking of surface coating is a common problem due to heat concentration in laser nitriding process. Conventionally, the cracks can be avoided through heat treatment, which may have an important influence on the mechanical properties of coating. Crack-free TiN/Ti3Al IMC coatings on Ti6Al4V are prepared by plasma spraying and laser nitriding. The microstructures, phase constitutes and compositions of the coating are observed and analyzed with scanning electron microscopy(SEM), X-ray diffraction(XRD) and X-ray energy-dispersive spectroscopy(EDS). Microhardness, elastic modulus, fracture toughness of the coating are measured. The results show that the crackand pore-free IMC coatings can be made through the proposed method; with increasing laser power, the amount and density of TiN phase in the coating first increased and then decreased, leading to the similar trend of microhardness and elastic modulus and the reverse trend of fracture toughness of the coating. Both the average microhardness and elastic modulus of the coating increase three times higher than those of the substrate. The volume fraction of the TiN reinforced phase in composite can be controlled by varying the laser power and the cracking problem in laser nitriding process is successfully solved.
Laser nitriding is one of the effective techniques to improve the surface properties of titanium alloys and has potential application in the life extension of last-stage steam turbine blades. However, cracking of surface coating is a common problem due to heat concentration in laser nitriding process. Conventionally, the cracks can be avoided through heat treatment, which may have an important influence on the mechanical properties of coating. Crack-free TiN/Ti3Al IMC coatings on Ti6Al4V are prepared by plasma spraying and laser nitriding. The microstructures, phase constitutes and compositions of the coating are observed and analyzed with scanning electron microscopy (SEM), X-ray diffraction (XRD) and X-ray energy-dispersive spectroscopy (EDS). Microhardness, elastic modulus, fracture toughness of the coating are measured. The results show that the crack- and pore-free IMC coatings can be made through the proposed method; with increasing laser power, the amount and density of TiN phase in the coating first increased and then decreased, leading to the similar trend of microhardness and elastic modulus and the reverse trend of fracture toughness of the coating. Both the average microhardness and elastic modulus of the coating increase three times higher than those of the substrate. The volume fraction of the TiN reinforced phase in composite can be controlled by varying the laser power and the cracking problem in laser nitriding process is successfully solved. ? Chinese Mechanical Engineering Society and Springer-Verlag Berlin Heidelberg 2013.