Silicon nitride ceramic sintered body and preparation method thereof

US11919824B2 · kind B2 · utility

Assignees

• LANZHOU INSTITUTE OF CHEMICAL PHYSICS, CAS · CN
• Yantai Zhongke Research Institute of Advanced Materials and Green Chemical Engineering · CN
• Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing · CN

Inventors

• Zhuhui Qiao · Yantai, CN
• Lujie Wang · Lanzhou, CN
• Tongyang Li · Lanzhou, CN
• Ziyue Wang · Lanzhou, CN
• Yuan Yu · Yantai, CN
• Huaguo Tang · Yantai, CN

Key dates

• Filing date: May 19, 2023
• Grant date: Mar 5, 2024
• Expiry date: May 19, 2043

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C04B2235/96
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Disclosed are a silicon nitride ceramic sintered body and preparation method thereof. The silicon nitride ceramic sintered body includes a sintered bulk and a hard surface layer having a thickness of 10-1000 μm, formed on a surface of the sintered bulk, wherein the sintered bulk comprises a first silicon nitride crystalline phase and a first grain boundary phase; the hard surface layer comprises a second silicon nitride crystalline phase and a second grain boundary phase; the first grain boundary phase comprises a metal tungsten phase being tungsten elementary substance and/or a tungsten alloy; the second grain boundary phase comprises tungsten carbide particles; tungsten element in the metal tungsten phase accounts for 80-100 wt % of total tungsten element in the first grain boundary phase; and tungsten element in the tungsten carbide particles accounts for 60-100 wt % of total tungsten element in the second grain boundary phase.