Solubility Limits of α'‐SiAION Solid Solutions in the System Si,Al,Y/N,O

The solubility limit of {alpha}{prime}-SiAlON solid solutions on the Si{sub 3}N{sub 4}-YN:3AlN composition join in the system Si{sub 3}N{sub 4}-YN-AlN has been determined at 1800{degrees}C. The end members of these solid solutions are Y{sub 0.43}Si{sub 10.7}Al{sub 1.3}N{sub 16} and Y{sub 0.8}Si{sub 9.6}Al{sub 2.4}N{sub 16}. Unit-cell dimensions of the {alpha}{prime}-SiAlON solid solutions in the system Si,Al,Y/N,O can be expressed as follows: a{sub 0} ({Angstrom}) = 7.752 + 0.045m + 0.009n, c{sub 0} ({Angstrom}) = 5.620 + 0.048m + 0.009n, where the {alpha}{prime}-SiAlON solid solution has the formula Y{sub x}Si{sub 12{minus}(m + n)}Al{sub m+n}N{sub 16{minus}n}O{sub n}. The single-phase boundary of the solid solution {alpha}{prime}-SiAlON on the composition triangle Si{sub 3}N{sub 4}-YN:3AlN-Al;N:Al{sub 2}O{sub 3} is delineated. The present paper also reports the phase relationships involving {alpha}{prime}-SiAlON.