Consolidation of MA W-Ni-Fe Alloyed Powder by Microwave-Assisted Sintering

Wensheng Liu, Yunzhu Ma, Qingshan Cai

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DOI: 10.4236/msa.2011.26082                

Abstract

MA W-Ni-Fe alloyed powder compact was sintered by microwave technology, and the influence of microwave sintering on consolidation of W-Ni-Fe alloy was studied. The fracture morphology and microstructure of alloys were measured by SEM and metallurgical microscope. The experimental results showed that microwave sintering promoted the densification of MA W-Ni-Fe alloyed powder quickly with the higher heating rate. The density of the sintered samples increased with the increase of sintering temperature, and significant densification shrinkage occured at 1300 ~ 1400°C. The tungsten grain grew rapidly at 1450°C. When the alloy was microwave sintered at 1550°C, the inner structure of alloy is more homogeneous, the average W grain size is about 15 μm, and the relative density of sintered specimen is 99%.

Keywords

W-Ni-Fe Alloy, Microwave Sintering, Consolidation

Conflicts of Interest

The authors declare no conflicts of interest.

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