As it is difficult to obtain full densification of W-Ni-Mn alloy during sintering, a novel hydrogen sintering technology has been employed based on the conventional one. The relative density of 90W-4Ni-6Mn alloy reaches 98.32%without full densification, which indicates that there are some irregular pores and manganese oxide remaining. Then, in order to get the alloy densify fully, vacuum-argon sintering process has been developed, by which the relative density of 90W-4Ni-6Mn alloy can be as high as 99.82%, approximately full densification. In addition, the mechanical properties of the sample were tested, as well as the microstructure and fracture morphology were investigated by scanning electron microscope (SEM). The results show that with increasing the holding time of pre-sintering, the tensile strength and elongation increase gradually, reaching the maximum value of 1 030.25 MPa and 24.2%, respectively, when the holding time of pre-sintering is 100 min with the average tungsten grain size only being 6.2μm. It’s concluded that the excellent properties of 90W-4Ni-6Mn alloy stem from the increase of sintered density and refinement of tungsten grain size.%针对 W-Ni-Mn 合金难以烧结致密化的问题，在传统氢气烧结工艺的基础上，发展新型氢气烧结工艺，使90W-4Ni-6Mn合金的相对密度达到98.32%，但仍未达到全致密，并存在部分形状不规则的孔隙和锰的氧化物。为使合金能够烧结全致密，本文再次开发了一种新的真空-氩气烧结工艺，使90W-4Ni-6Mn合金的相对密度高达99.82%，近乎全致密。对合金进行力学性能测试，并利用扫描电镜(SEM)观察其微观结构和断口形貌，结果表明：90W-4Ni-6Mn 合金的抗拉强度和伸长率均随预烧结保温还原时间延长而增大，在100 min 时达最大值，分别为1030.25 MPa和24.2%，此时钨晶粒尺寸为6.2μm。经分析，90W-4Ni-6Mn合金的优异性能主要得益于烧结密度的提高和晶粒尺寸的细化。
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