Fabrication of in-situ self-reinforced Si3N4 ceramic foams for high-temperature thermal insulation by protein foaming method. Issue 13 (1st July 2021)

• Record Type: Journal Article
• Authors: Yang, Feiyue; Yao, Yiwen; Yang, Zichun; Zhao, Shuang; Chen, Guobing; Li, Kunfeng
• Is Part Of: Ceramics international. Volume 47:Issue 13(2021)
• Page Start: 18351
• Page End: 18357
• Publication Date: 2021-07-01
• Subjects: Self-reinforced ceramic foams -- Microstructure -- Thermal conductivity -- Compressive strength -- High-temperature oxidation resistance; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2021.03.156
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: To meet demand for lightweight and high-strength ceramic foams, in-situ self-reinforced Si3 N4 ceramic foams, with compressive strength of 13.2–45.9 MPa, were fabricated by protein foaming method combined with sintered reaction-bonded method. For comparison, ordinary protein foamed ceramics with irregular block microstructure were fabricated via reaction-bonded method, which had compressive strength of 3.6–20.5 MPa. Physical properties of these two types of samples were systematically compared. When open porosity was about 80%, both types of Si3 N4 ceramic foams had excellent thermal insulation properties (<0.15 W m −1 K −1 ), while compressive strength of in-situ self-reinforced samples increased by more than 158% compared with ordinary samples. Under high-temperature oxidation conditions, microstructures of both types of samples were deformed with increase in oxidation temperature. Moreover, after oxidation temperature was increased to 1400 °C, oxidation weight gain decreased from 18.07% for ordinary samples to only 2.18% for self-reinforced samples. Thus, high-temperature oxidation resistance of Si3 N4 ceramic foams was greatly improved.