Study On Manufacture And Microwave-Absorption Properties Of The New Type Absorption Material Nd_8-XYFe_84.5+XB_6.5 (x=0, 0.5, 1)

A novel absorption material is obtained after vacuum smelting,steelball pulverizing and proper annealing disposal.At the same time,their microwave absorption property is studied.The result shows that the absorption property of the material which pulverized at different time is different;The anneled and steelball absorption property is better than the one without anneled,and the material absorption property is best when annealed time and the content of Fe are proper.At the same time,we have also studied the anti-oxidant property change of the material when doped with yttrium.In the chemical proportion of molecular of Nd_8xYFe_84.5+xB_6.5(x=0,0.5,1), material absorption property is best when x=0.5 without annealed,and the highest absorption value is 36.843dB,compared with x=0,1,the value increases obviously.The above indicates that the absorption property of these materials doesn't change as the mount of Fe regularly,only doping proper a mount of Fe can improve its microwave absorption property.The absorption property of the annealed material increases obviously than the one without annealed,When annealed for 15min,the absorption property is at best,the highest absorption value is 137.36dB,and the average absorption has the height of 10dB than the one annealed for 10min or 20min.Therefore,the annealed time can get a proper value.After the sample pulvevized at different time(t=6h,8h,10h,12h),the microwave absorption property is best when the sample pulvevized for 8h.The above indicates that the absorption property of these materials doesn't change as the time of pulverized regularly,but there exists a matching time.The extent of weakening of the absorption property value of the sample that doped with yttrium is smaller than the one without doped with yttrium in the air after a period of time.Therefore,the anti-oxidant property is strengthened when the sample is doped with yttrium.In order to study the microwave-absorbing mechanism,imagionary part of permeability,dielectric constent and XRD spectrum of the sample are measured.The results of experiments indicate that the frequency corresponding to the peak of imagionary part of permeability is close to the one corresponding to the peak of absorption when the sample without annedled,and their changing rules of the peak of imagionary part of permeability and absorption change with frequency are similar.Therefore,the absorption property of the sample without annealed rests on imagionary part of permeability,but the frequency corresponding to the peak of imagionary of dielectric is close to the one corresponding to the peak of the absorption.And their changing rules of the peak of imagionary part of dielectric constent are similar when the sample annealed.From the XRD spectrum,we can see that the sample formed the configuration that the oxid and metal particulate distribute symmetrically according to cubage,which provides a finer absorbing way for the sample.