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在高温（１４００℃）和超高压（４．２ＧＰａ）条件下制备部分稳定ＺｒＯ_２增韧的Ｓｉ_３Ｎ_４中介结合的聚晶立方氮化硼（ＰＣＢＮ），研究了中介相中ＺｒＯ_２的相变及增韧机理．在ＰＣＢＮ中加入少量Ａｌ粉，可阻止ｔ－ＺｒＯ２形成，达到利用部分稳定的ＺｒＯ２的ｔ－ｍ相变增韧中介相Ｓｉ３Ｎ４的目的．ＺｒＯ_２的ｔ－ｍ相变量在稳定剂Ｙ_２Ｏ_３含量为２．０％（摩尔分数）时达到最大值，ＰＣＢＮ具有较高的抗压强度和磨耗比．ＺｒＯ２对中介相的增韧机理为相变增韧与微裂纹增耕作用的叠加．
The partially stabilized ZrO_2-toughened Si_3N_4 intercalated polycrystalline cubic boron nitride (PCBN) was prepared under high temperature (1400 ℃) and ultra-high pressure (4.2GPa). The phase transformation and toughening mechanism of ZrO_2 in interphase . Adding a small amount of Al powder to PCBN can prevent the formation of t-ZrO2 and achieve the purpose of toughening the intermediate phase Si3N4 by using the partially stabilized zirconium oxide. The t-m phase change of ZrO 2 reaches the maximum value when the content of stabilizer Y 2 O 3 is 2.0% (mole fraction), and PCBN has higher compressive strength and wear ratio. The toughening mechanism of ZrO2 on the interphase phase is the superposition of the effect of phase transformation toughening and micro-crack growth enhancement.