An Extension of the liquid-forming region in the M-Si-Al-O-N system

A review of some behaviour diagrams in the Y-Si-Al-O-N system indicated that the liquid region, and hence the glass forming region, could be more extensive than previously documented. Apart from the glass-forming region of Drew et al [1] at 1700°C, a further liquid region at 1550°C was proposed by Hohnke and Tien [2]. However the region between these had not been systematically explored. Other researchers [3] have looked at the nitrogen-rich liquid phase regions in the Ln-Si-Al-O-N systems (40 e/o N). In the current study, selected compositions were sintered at 1550°C and 1700°C. The areas of glass formation are indentified for the different M-Si-Al-ON systems investigated.