Realizing load bearing-heat insulation integration of lightweight porosity-controlled SiC(rGO) bulk ceramics via precursor route for hypersonic vehicles. Issue 21 (1st November 2022)

• Record Type: Journal Article
• Authors: Huang, Wenyan; Liang, Jiahao; Zhuang, Kun; Mao, Shengjian; Zheng, Yinong; Zhu, Yeqi; Tao, Qianwen; Yao, Rongqian
• Is Part Of: Ceramics international. Volume 48:Issue 21(2022)
• Page Start: 31984
• Page End: 31994
• Publication Date: 2022-11-01
• Subjects: A. Precursors: organic -- D. SiC -- C. Thermal properties -- B. Porosity; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2022.07.134
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Realizing integration of admirable load bearing and outstanding heat insulation characteristics of porosity-controlled ceramics for hypersonic vehicles is a great challenge. Herein, an ingenious strategy based on re-pyrolysis process of ball-milling-induced fillers/precursors(pore-forming agents) blends is proposed to prepare porous SiC(rGO) bulk polymer-derived ceramics (PDCs) for thermal protection. During re-pyrolysis, dense integrated β-SiC/SiO x C y /Cfree (rGO) framework, belonging to SiC(rGO)p tightly tied by SiC(rGO) from polycarbosilane-vinyltriethoxysilane-graphene oxide (PCS-VTES-GO, PVG), can be formed to maintain brilliant mechanical properties of products. Meanwhile, good interfacial compatibility of nanocomposite structure within the framework also contributes to load capacity. A uniquely uniform distribution of dentinal tubules-like pores, originated from polystyrene (PS) in SiC(rGO) region, could relax stress at crack tips and ensure good thermal insulation. Particularly, lightweight porous SiC(rGO) bulk PDCs with 10 wt% PS content possess low thermal conductivity (0.25 W·m −1 ·K −1 ), excellent fracture toughness (1.96 MPa·m 1/2 ), outstanding hardness (3.58 GPa), optimal compressive strength (51.80 MPa) and good flexural strength (33.86 MPa). Their large-sized molding ability and good high-temperature oxidation resistance were significantly demonstrated by further exploration. Such well-balanced high load bearing and good heat insulation integration nature can be used to make thermal insulators with complex shapes in a facile and economical manner. Graphical abstract: Image 1 Highlights: Lightweight porosity-controlled SiC(rGO) bulk PDCs were ingeniously synthesized. The as-received products own well-balanced integration of load bearing-heat insulation. Dense integrated framework and good interfacial compatibility are vital for brilliant strength. Uniform distribution of dentinal tubules-like pores aims at relaxing stress at crack tips. Good high-temperature oxidation resistance is significantly demonstrated for hypersonic vehicles.