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Active magnetic thrust bearing (AMTB) is a device which is used to support an object by controlling the magnetic field. In practice, there is lot of difference between theoretical force and actual force developed between the stator and rotor of an AMTB. This difference is mainly due to fringing, leakage, variation in material properties, misalignments, vibrations, and temperature effects, etc. The difference is also varying with the air gap between stator and rotor and the current supplied. In this work, an experimental approach has been proposed to study the loss factor and efficiency of an Active Magnetic Thrust Bearing. A prototype of AMTB has been made and experimented at different air gaps. Based on the study of single acting actuator, the control performance of a double actuator has been studied. From the study of single acting actuator efficiency and double acting actuator control performance, an optimum air gap has been suggested. Keywords Active magnetic thrust bearings Á Correction factor Á Magnetic levitation Á Control system Á Air gap 1 Introduction An active magnetic bearing works on the principle of electromagnetic suspension. An active magnetic thrust bearing (AMTB) is a non-laminated circular magnetic actuator having

In the present work, Zn-HA composites were developed by powder metallurgy route targeted for bone implant applicaitons. Zn-HA powders with varying HA content (1, 2, and 4 wt.%) were ball milled for 1 hr and sintered to produce composite compacts. X-ray diffraction (XRD) studies were done for all the ball milled powders and sintered compacts. No impurities were observed in the ball milled powders. Microstructural observations revealed the formation of lamellar structure in the composites due to the plastic deformation of the Zn powders during ball milling. Grain size measurements revealed the decreased grain size with increase of addition of HA. Furthermore, aspect ratio (length to thickness ratio) of the grains was measured and found that the aspect ratio was also decreased with the increased HA content. Higher microhardness was measured for all the composites compared with pure Zn. However, composite with 1% has shown higher hardness compared with the remaining composites. Form the preliminary observations, it can be concluded that Zn-HA composites can be successfully produced with lamellar morphology by ball milling followed by sintering for biomedical applications with increased hardness.