Effect of Applied Pressure on Densification and Mechanical Properties of Sialon-ZrN Composites Fabricated Through a Reaction Bonding / Gas Pressure Sintering Process

2018 2nd International Conference on Advanced Technologies in Manufacturing and Materials Engineering

Yin, L.^1 ; Jones, M.I.^1

Department of Chemical and Materials Engineering, Faculty of Engineering, University of Auckland, Auckland

1023, New Zealand^1

关键词: Applied pressure;    Gas-pressure sintering;    Intermediate phasis;    Mass loss;    Pressure increase;    Reaction bonding;    Sintering process;    Weak bonding;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/389/1/012021/pdf
DOI  :  10.1088/1757-899X/389/1/012021

来源: IOP

【 摘 要 】

Sialon-ZrN composites have been produced by reaction bonding and gas pressure sintering, and the effects of applied pressure on the sintering and properties has been investigated. The results showed that composites were mainly composed of β-Sialon and ZrN, with intermediate phases (including Y2SiAlO5N, Al2SiO5 and Y2Si2O7) for 0.4 MPa and Y5Si4Al2O17N for 1.0 MPa. The mass loss decreased with pressure increase due to suppression of thermal decomposition of the Sialon. Composites sintered under 1.0 MPa had better densification than those sintered under 0.4 MPa, and presented greater mechanical properties. Under 1.0 MPa, compared to the monolithic Sialon, the addition of ZrN resulted in an increased hardness up to 30% ZrN, with the highest hardness of 16.16 GPa being observed with 20% ZrN. The hardness decreased with higher ZrN content due to the weak bonding between the ZrN particles and the Sialon matrix. However this resulted in a continuous increase in fracture toughness, reaching a maximum of 5.41MPa•m1/2 with 50% ZrN.