The Influence Of The Al Nanopowders On The Coercivity Of Strontium Ferrite By Crystal Boundary Modified

Sintered Nd-Fe-B permanent magnets, as the third generation of rare earth permanentmagnet, once available will be its excellent magnetic properties and good value, were called"Magneto."It is widely used in the production of various aspects of life, such as hard drives,NMR, and other high-tech fields of modern electronic devices. But the sintered Nd-Fe-Bpermanent magnets, further electrical and electronic equipment are going small andultra-compact,so moreworkneedto win themajorityof consumers.In order to improve the performance of large-scale industrial production of rare earthNd-Fe-B permanent magnets and savings rare earth, which were used to rejection with slicescrystallization process using nano-Al powder and secondary tempering process, to improvemagneticproducts and reduceenergycosts.In this production process, to produce various Nd-Fe-B samples, adding the mixingdifferent proportions of nano-Al powder, different crystallization treatment temperature anddifferent tempering process technology is necessary. And represent the properties by x-raydiffraction spectroscopy, scanning electron microscopy, particle size, and ATM-4meterfeatures automatic measuring instrument, such as the magnetization of our samples testedproduced. The experimental results were compared and analyzed, the concludtions areperformed: using crystallization treatment process (700℃, insulation15min) the production ofNd-Fe-B quenched amorphous ribbons have been completely disappeared under the sameconditions, the magnetic properties of the sample can also reach the optimum value, the residualmagnetism is1.400T, intrinsic coercivity is1026.84kA/m, the maximum energy product is375.075KJ/m3. Tempering treatment process are using two steps (920℃,thermostat3hours,560℃, thermostat5hours) to produce the sample in the orientation of the main phase(00i) in the direction of significantly enhanced to reduce the content of the sample of ɑ-Fe.Meanwhile, we compared with the level of the tempering process by using a sampleprocessing, remanence, coercivity and maximum energy integration are improved to5.98%, 21.79%,16.75%than before. By adding different proportions of nano-Al powder duringmixing,andwhentheamount of nano-Al powder was0.3wt%, the grain boundaries of the sample was very clearand very uniform grain size, better suppression of the hard magnetic phase the exchangecoupling, and Al elements in the success of the grain boundaries instead of rare earth elementsNd, the coercivity of the sample has reached the optimum value of1127KA/m. The result aresaving someextentRE Ndandreducingtheproductioncost.