Abstract High-density WC–Ni composite ceramics were prepared by cold isostatic pressing–vacuum pressureless sintering–hot isostatic pressing with tungsten carbide (WC) powder and NiCl2·6H2O as a binder. Results show that with an increase in the contents of Ni in the metal binder phase, the relative density of WC–Ni composite ceramics is improved, and the formation of the carbon-deficient W2C phase is reduced. There is no W2C generated in the WC–1 wt% Ni material. At high temperatures, the Ni phase changes into the liquid phase and enters between the WC particles, thereby promoting the close alignment of the WC particles. Moreover, the WC particles will be more closely aligned under their own surface tension and capillary action, thereby promoting the densification of WC–Ni composite ceramics. The WC–0.5 wt% Ni composite ceramics are fully dense and show the best comprehensive performance with a microhardness of 23.0 GPa, a fracture toughness of 5.28 MPa m1/2, and a flexural strength of 1,396.58 MPa. WC–Ni composite ceramics are mainly composed of elongated triangular prism WC particles and Ni phase. Transgranular fracture was the main fracture mode of WC–Ni multiphase ceramic materials with a small amount of intergranular fracture due to the existence of the Ni phase. Such a fracture mode can increase the flexural strength of the composite material. Graphical abstract

中文翻译：

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NiCl2·6H2O为粘结剂的WC-Ni多相陶瓷材料的显微组织和力学性能

摘要 以碳化钨（WC）粉末和NiCl2·6H2O为结合剂，通过冷等静压-真空无压烧结-热等静压制备高密度WC-Ni复合陶瓷。结果表明，随着金属粘结相中Ni含量的增加，WC-Ni复合陶瓷的相对密度提高，缺碳W2C相的形成减少。在 WC–1 wt% Ni 材料中没有生成 W2C。在高温下，Ni相转变为液相并进入WC颗粒之间，从而促进WC颗粒的紧密排列。此外，WC颗粒在其自身的表面张力和毛细管作用下会更加紧密地排列，从而促进WC-Ni复合陶瓷的致密化。WC-0。5 wt% Ni复合陶瓷致密,综合性能最佳,显微硬度为23.0 GPa,断裂韧性为5.28 MPa·m1/2,抗弯强度为1,396.58 MPa。WC-Ni复合陶瓷主要由细长的三棱柱WC颗粒和Ni相组成。穿晶断裂是WC-Ni多相陶瓷材料的主要断裂方式，由于Ni相的存在，有少量沿晶断裂。这种断裂模式可以增加复合材料的弯曲强度。图形概要 穿晶断裂是WC-Ni多相陶瓷材料的主要断裂方式，由于Ni相的存在，有少量沿晶断裂。这种断裂模式可以增加复合材料的弯曲强度。图形概要 穿晶断裂是WC-Ni多相陶瓷材料的主要断裂方式，由于Ni相的存在，有少量沿晶断裂。这种断裂模式可以增加复合材料的弯曲强度。图形概要