Zinc Tungstate Whisker

Whisker is a kind of fiber which grows in single crystal form under artificial control.
 
zinc tungstate whisker image
 
Whisker's diameter is very small (micron order of magnitude), no defects in the usual materials (grain boundaries, dislocations, voids, etc.). Its atomic arrangement is highly ordered, so its intensity is close to the theoretical value of the complete crystal. Because the whisker reinforced composites have the potential of high strength, the research and development of whiskers have been paid much attention to.
 
Zinc tungstate whisker is mainly used in metal matrix composites, and it is a key high-tech material. It has been widely used in ceramic cutting tools, space shuttles, automobile parts, chemical industry, machinery and energy production. 
 
Zinc tungstate has a better scintillation performance than the currently widely used scintillation crystal, but also has the characteristics of not deliquescence and low price, and is a very promising scintillation crystal. The size of zinc tungstate whiskers is generally about 200~500nm, and it is unlikely to have obvious quantum size effect, therefore, scholars believe that the blue shift of the luminescence peak should be due to the crystal structure of the whisker is more complete, less defects, that is, the whisker growth of zinc tungstate is not difficult. 
 
Zinc tungstate whisker is prepared by solid phase sintering, that is, by mixing tungstic acid and tungsten oxide powder, ball milling, drying, grinding, sieving, tableting, sintering and other technological processes, finally, zinc tungstate whiskers were successfully prepared. Analysis of whisker structure with the XRD, found the structure of wolframite structure, smooth surface, thickness of single whisker is consistent, its cross section is round, the top of the whisker is sharp, and the growth of the whisker is best when the ratio of tungstic acid to tungsten oxide is 4:1, the sintering temperature is 1150 degrees, and the holding time is 240 min.
 

 

 

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