Sintering behaviour of spinel�?�alumina composites

Bulletin of materials science

S Mukherjee¹  B N Samaddar²  P G Pal³  A K Bandyopadhyay³  Soumen Pal³ 

[1] School of Material Science & Technology, Jadavpur University, Kolkata 700 032, India$$School of Material Science & Technology, Jadavpur University, Kolkata 700 032, IndiaSchool of Material Science & Technology, Jadavpur University, Kolkata 700 032, India$$;Ex-emeritus Professor (AICTE), Department of Metallurgical & Material Engineering, Jadavpur University, Kolkata 700 032, India$$Ex-emeritus Professor (AICTE), Department of Metallurgical & Material Engineering, Jadavpur University, Kolkata 700 032, IndiaEx-emeritus Professor (AICTE), Department of Metallurgical & Material Engineering, Jadavpur University, Kolkata 700 032, India$$;Department of Ceramic Technology, Govt. College of Engineering & Ceramic Technology, Kolkata 700 010, India$$Department of Ceramic Technology, Govt. College of Engineering & Ceramic Technology, Kolkata 700 010, IndiaDepartment of Ceramic Technology, Govt. College of Engineering & Ceramic Technology, Kolkata 700 010, India$$

关键词: Sintering;    stoichiometric spinel;    spinelâ€�?�alumina composites;    solid-solution.;   

DOI  :  

学科分类：材料工程

来源: Indian Academy of Sciences

【 摘 要 】

Study of aluminaâ€�?�magnesia binary phase diagram reveals that around 40â€�??50 wt% alumina dissolves in spinel (MgAl₂O₄) at 1600°C. Solid solubility of alumina in spinel decreases rapidly with decreasing temperature, which causes exsolution of alumina from spinel phase. Previous work of one of the authors revealed that the exsolution of alumina makes some interlocking structures in between alumina and spinel phases. In the present investigation, refractory grade calcined alumina and spinel powder were used to make different batch compositions. Green pellets, formed at a pressure of 1550 kg cm^-2 were fired at different temperatures of 1500°, 1550° and 1600°C for 2 h soaking time. Bulk density, percent apparent porosity, firing shrinkage etc were measured at each temperature. Sintering results were analysed to understand the mechanism of spinelâ€�?�alumina interactions. SEM study of present samples does not reveal the distinct precipitation of needle shaped ð›�?-alumina from spinel, but has some effect on densification process of spinelâ€�?�alumina composites. Microstructural differences between present and previous work suggest an ample scope of further work in spinelâ€�?�alumina composites.

【 授权许可】

Unknown