Preparation of highly toughened Ti(C,N)-based cermets via mechanical activation and subsequent in situ carbothermal reduction

• Published in: International journal of refractory metals & hard materials 2020-11, Vol.92, p.105310, Article 105310
• Main Authors: Xu, Xiangyu, Zheng, Yong, Zhang, Guotao, Yang, Zhengkai, Ke, Zheng, Wu, Hao, Lu, Xuepeng
• Format: Article
• Language: English
• Subjects: Alloying elements; Atomic emission spectroscopy; Ball milling; Carbothermal reduction; Cermets; Chemical composition; Chemical reduction; Complete solid solution; Emission analysis; Highly toughened; Inductively coupled plasma; Mechanical activation; Microstructure; Phase transitions; Sintering (powder metallurgy); Solid solutions; Ti(C,N)-based cermet
• ISSN: 0263-4368; 2213-3917
• DOI: 10.1016/j.ijrmhm.2020.105310

Highly toughened Ti(C,N)-based cermets were successfully fabricated using a novel method of mechanical activation and subsequent in situ carbothermal reduction. The phase transformation, chemical composition, and microstructure of the mechanical activation powders and as-sintered cermets were investigated using XRD, ICP-AES, C/N/O analysis, and SEM. The results revealed that the complex MoNiTi solid solution phase formed after mechanical activation, and the powders after high energy ball milling promoted the solid solution of alloying elements into the hard particles. After the subsequent sintering process containing the in-situ carbothermal reduction reaction and liquid sintering, the microstructure of as-sintered cermet showed a single solid solution phase with a homogenous distribution. Without added WC, the extremely high toughness of the present cermet was 21.3 MPa·m1/2, and this was 66.4% higher than that of the conventional cermet and 62.5% higher than that of the cermet that was fabricated via in-situ carbothermal reduction. •Highly toughened cermets were preparedby a novel method of mechanical activation and subsequent in situ carbothermal reduction.•The fabrication of cermets exhibit a single solid solution phase without core–rim microstructure.•This approach producing a high toughness cermet with uniform complete solid solution phase in one thermal cycle process.•The cermet using the novel method showed a better comprehensive mechanical properties than that of traditional cermets.