| Porous metal materials with characteristics of structural materials and functional materials have become one of the hotspots.Zr-V-Fe alloy is one of the most widely used non-evaporable getters as it has low activation temperature and good suction effect at room temperature,so it is used in a variety of electronic vacuum devices.But the formation methods of this device with small and regular shape are rarely reported in the literature.In this paper,porous Zr-V-Fe alloy devices were preparaed by using the slip casting method with Zr-V-Fe alloy powder which has the average particle size of 30-40?m.It focused on the research of its design which contains ball milling of Zr-V-Fe alloy powder,preparation and molding of Zr-V-Fe slurry and degumming and sintering of green Zr-V-Fe,using differential thermal analysis thermogravimetric analysis(DSC-TG)and scanning electron microscope(SEM)testing methods,so it can get an optimum route preparation of porous Zr-V-Fe alloys.Firstly,the effect of ball milling time,ball diameter,and the ratio of ball/materials for Zr-V-Fe powders were studied.It was found that increase of the ratio of ball/material and ball milling time can reduce the average size of particles.When the ratio of ball/material is 20:1,the particle sizes for ball milling time of 10 hours and 20 hours are nearly,which showed that ball milling time has no influence on particle size this case.In the case that the ball milling time and ball material ratio are fixed,the decrease of diameter of the ball can make the raw material much smaller.When the media is water,the diameter of milling ball is 8:5:3,the ratio of their weight is 1:2:2,the ratio of material and water is 1:1,the ratio of ball and raw material is 3:1 and the ball milling time is15 hours,the average size of Zr-V-Fe particles can be got to 5-8 ?m.These particles showed good dispersivity and thus is suitable for slip casting.The influence of the content of solid phase and ball milling time had been studied for green body of Zr-V-Fe alloy.Increasing ball milling time can improve the liquidity and uniformity of the slurry.Higher solid content can reduce the influence of organic solvents for final green body.However,with improving the content of solids phase,the milling.progress requires a long time.The results showed when the radio of ball and slurry is 1:1,the content of solids phase is 50%,ball milling 30 hours for the green body is available for moulding.To study the process of degumming and sintering green body,DSC-TG method was adopted.It showed degumming for an hour at 500? could exclude the organic solvents completely.The influence of different sintering temperature was studied on the porosity and morphology of porous Zr-V-Fe alloy.The optimal of sintering was obtained:high vacuum atmosphere,sintering temperature at 750 ? condition for 2hours of.Finally,the device of porous alloy Zr-V-Fe with 17.64%?20.05%porosity was prepared.In summary,small and porous device of Zr-V-Fe alloy was prepared simply by a slip casting method,which showed potential application for the Zr-V-Fe alloy. |
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