Microstructure and Properties of Gradient Ti(C,N)-Based Cermets by Powder Extrusion Additive Manufacturing

Ti(C,N)-based cermets are crucial for high-speed cutting tools and other high-temperature applications, yet there remains a considerable gap in their preparation controllability, fracture strength, and toughness compared to cemented carbide. Despite numerous studies having focused on modifying the hardness and toughness of Ti(C,N)-based cermets by varying process parameters and chemical compositions, this research has used gradient Ti(C,N)-based cermets produced by powder extrusion additive manufacturing (PEM) technology, which is rare. This study developed the gradient structure layer by layer using PEM. The microstructure of the printed and sintered parts was studied, and the hardness, fracture toughness, and bending strength of the gradient material were analyzed. The gradient material demonstrates superior mechanical properties compared to traditional Ti(C,N)-based cermets, with a hardness of 1760−23+39 HV20, a fracture toughness of 8.5−0.4+0.3 MPa·m1/2, and a bending strength of 2047−43+22 MPa. The research will assist researchers in assessing the potential application of PEM and broaden the application fields of gradient Ti(C,N)-based cermets.