The control of liquid phase migration or liquid redistribution is crucial for the fabrication of graded W-Ni-Fe alloys with Mo addition by liquid phase sintering. The driving force of liquid phase migration is liquid migration pressure Pm which depends on the variation of interfacial tension and grain size. In the present paper, the effects of interfacial tension and grain size on liquid phase migration have been studied experimentally for W (Mo)-Ni-Fe system. A kinetic model was used to describe the diffusion of Mo and the migration of liquid phase. The results show that both the gradient of interfacial tension and grain size are contributed to the migration of liquid phase. The migration velocities of liquid phase induced by gradient of grain size and Mo distribution were calculated respectively.%在液相烧结制备的含Mo梯度W-Ni-Fe合金中，对液相迁移或液相再分布的控制极为关键。液相迁移的驱动力为液相迁移压(Pm)，而液相迁移压主要由界面张力和晶粒尺寸的变化所引起。本研究从实验角度探究W(Mo)-Ni-Fe体系中界面张力和晶粒尺寸对液相迁移的影响，并通过动力学模型来描述Mo的扩散和液相迁移。结果表明界面张力梯度与晶粒尺寸梯度均有助于液相的迁移，并且算得由晶粒尺寸和Mo分布梯度诱导的液相迁移速率分别为4.807×10-4 kg/m2s和8.117×10-4 kg/m2s。
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