Insights into arc-assisted self-propagating high temperature synthesis of TiB2-TiC ceramic coating via wire-arc deposition. Issue 13 (October 2020)

• Record Type: Journal Article
• Authors: Bao, Yang; Huang, Lujun; An, Qi; Jiang, Shan; Zhang, Rui; Geng, Lin; Ma, Xinxin
• Is Part Of: Journal of the European Ceramic Society. Volume 40:Issue 13(2020)
• Page Start: 4381
• Page End: 4395
• Publication Date: 2020-10
• Subjects: Self-propagating high temperature synthesis (SHS) -- TiB2-TiC ceramic coating -- Boron carbide -- Wire-arc deposition -- Hardness; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2020.05.005
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: TiB2 -TiC ceramic coating was fabricated by wire-arc deposition of Ti-B4 C cored wire in conjunction with self-propagating high temperature synthesis (SHS) technology, to enhance the hardness and wear resistance of Ti. Results showed that a periodic combustion reaction, triggered by the capillary infiltration of molten Ti sheath into the inside B4 C particles, occurred as the wire entered the arc zone. During combustion reaction, B4 C experienced the course of dissolution as well as the transformation of decarbonization expressed as B4 C→B13 C2 →B13 Cx(1.27<x<2.00) . In particular, the loss of C was more notable at combustion front region. The as-synthesized coating exhibited ultralow porosity thanks to the elevated adiabatic temperature, and possessed gradient microstructures formed due to the dissolution-precipitation mechanism. Mechanical and tribological tests showed that the coating had ultrahigh microhardness (2140 HV0.5, close to theorical value) and low wear rate (5.5×10 −3 mm −3 min -1 ·N -1 ). The superior performance was attributed to ultralow porosity and high-strength coherent TiB2 /TiC interface.