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本文研究了Y_2O_3-Al_2O_3-Si_2N_2O系统的亚固相关系和1550℃的等温面相关系。研究结果表明,Si_2N_2O可与小于15mol％的Al_2O_3形成O′-Sialon(O′_(s.s.))。2Y_2O_3·Si_2N_2O可与2Y_2O_3·Al_2O_3形成连续固溶体(J_(s.s.)).在Y_2O_3-Al_2O_3-Si_2N_2O系统的Si_2N_2O一端,Si_2N_2O与Y_2O_3会反应生成Si_3N_4和Y_(10)[SiO_4]_6N_2(H相)。因此在该系统中有四个四元相区:H-Si_2N_2O-O′_(s.s.)-Si_3N_4,H-3Y_2O_3·5Al_2O_3-O′_(s.s.)-Si_3N_4,H-3Y_2O_3·5Al_2O_3-Y_2O_3·Si_2N_2O-Si_3N_4,H-3Y_2O_3·5Al_2O_3-Y_2O_3·Si_2N_2O-J_(s.s.).在1550℃等温面相图中,在近Al_2O_3-Si_2N_2O系统一边有一个很大的液相区。其低共熔组成为:Y_2O_3:2Si_2N_2O:2Al_2O3,T=1450℃。
In this paper, the relationship between the subsolidus phase of Y_2O_3-Al_2O_3-Si_2N_2O system and the isothermal surface phase of 1550 ℃ has been studied. The results show that Si 2 N 2 O can form O’-Sialon (O ’_ (s.s.)) With less than 15 mol% Al 2 O 3. 2Y_2O_3.Si_2N_2O can form continuous solid solution with 2Y_2O_3 · Al_2O_3 (J ss.) In the Y_2O_3-Al_2O_3-Si_2N_2O system, Si_2N_2O can react with Y_2O_3 to form Si_3N_4 and Y_ (10) [SiO_4] _6N_2 (H phase) at one end of Si_2N_2O in Y_2O_3-Al_2O_3-Si_2N_2O system. Therefore, there are four quaternary phases in this system: H-Si_2N_2O-O ’_ (ss) -Si_3N_4, H_3Y_2O_3 · 5Al_2O_3-O’ _ (ss) -Si_3N_4, H_3Y_2O_3 · 5Al_2O_3-Y_2O_3 · Si_2N_2O In the 1550 ℃ isothermal phase diagram, there is a large liquid region on the side of Al 2 O 3 -Si 2 N 2 O near the Al 2 O 3 -Si 2 N 2 O system. Its eutectic composition: Y_2O_3: 2Si_2N_2O: 2Al_2O3, T = 1450 ℃.