The synthesis of silver coated iron base alloy (Sendust : Fe-Si-Al) powder having the both effects of shielding and suppressing of electromagnetic wave was studied. Depending on thickness of silver coating layer, the electromagnetic properties of the dispersed particles complexed with organic binder were examined. It is proposed that the silver coated sendust flake powders with controlled electrical properties and thickness can be used as thin microwave absorbers in quasi-microwave frequency band.

Eventhough Fe-6.5 wt.% Si alloy shows excellent magnetic properties, magnetic components made of the alloy are not totally because of its extremely low ductility. In order to overcome this demerit of alloy, 6.7 wt.% Si alloy powders were produced by gas atomization and then post-processed to form magnetic cores. By doing so, the total core loss could be minimized by reducing both hysteresis and eddy current loss. From our experiments, we were able to achive a core loss of at 0.1 T and 50 kHz through proper processes and a permeability of 68 at low frequency.

Conductive pastes consist of conductive fillers( Au, Ag, Ni, Cu etc.), organic binders, solvents and additives. Meanwhile, there are some metal powders such as copper, nickel etc that are used for pastes which have serious surface corrosion problems. This problem leads to change of the color and decrease in conductivity and affect storage stability of conductive pastes. By using silane coupling agent and dispersion agent, we can ensure both the corrosion stability and long term storage stability, and enhance the high performance electrical and mechanical properties of EMI shielding silicone sealant.

Magnetic powder core is considered to be one of the essential parts in modern electronic devices such as power supplies, digital telecommunication equipments and automotive electronics. To satisfy the recent requirement for the miniaturization of micro-systems and portable devices, the inductors or magnetic powder cores should have reduced compact volume and high universality both in magnetic and geometric aspects. In contrast, in some application areas such as power converters, the price is also one of the important aspects to be considered. To comply with such stringent technical requirements in modern electronic industry, it is highly required to develop magnetic materials with increased frequency stability, higher saturation magnetic flux density, higher permeability and higher quality factor (Q). The magnetic alloy powders which are currently being used in PM industry are permalloy (Ni-Fe), sendust (Fe-Si-Al), iron (Fe), silicon steel (Fe-Si) and ferrous amorphous alloy powders. Recent research trends for the industrial application of soft magnetic material and magnetic powder core will be introduced in the present paper. Emphasis will be placed on the newly required properties and corresponding new PM technologies for newly emerging application fields such as hybrid electric vehicle, alternative and renewable energy systems for next generation.