Synthesis and characterization of Nd2Fe14B powder by using mechanical milling of flakes NdFeB
Ramlan, Dedi Setiabudidaya, Suprapedi, Amminudin, Muljadi
Physics Department, MIPA UNiversity Sriwijaya Palembang
Reseach Center for Physics LIPI
Abstract
Alloy of NdFeB powder is used for manufacture of permanent magnet and it has highest magnetic properties compared to other permanent magnet materials such as : Ba-ferrite, AlNiCo and SmCo.The Flakes of NdFeB was made by melt spinn method and it has about 0.2 – 0.3 mm in thickness. The flakes of NdFeB was milled by using High Energy Milling (HEM) machine and used a liquid toluene as milling media. The milling time was varried such as : 30, 60, 90, and 120. After milling, the samples were dried by using Vacuum dryer at temperature 80oC under vacuum (10 mmbar) for 2 hours. The fine powder samples were analyzed crystall structure by using XRD, measured magnetic properties by using VSM and also measured particle size distribution (PSA). The characterization result show that the milling time gives a effect on the crystall structure and magnetic properties, where samples with milling time 60 dan 90 minutes has Fe phase as dominant phase and the Nd2Fe14B phase does not existing also the coercivity value tends to decrease until lower than 100 Oe. Samples with milling time about 30 and 60 minutes have Fe phase and Nd2Fe14B phase also they have corecivity value about 850 – 1040 Oe. The means of particle size is achieved about 1.44 µm at sample with milling time 60 minutes.
Keywords: Magnet Nd2Fe14B, Flakes NdFeB, HEM, coercivity
Topic: Metal alloys, ceramics and composite materials