Method for manufacturing [mu]75 composite magnetic powder core

Abstract

The invention discloses a method for manufacturing a [mu]75 composite magnetic powder core. The method comprises the steps of powder compounding, passivation, insulation coating, press molding, heat treatment, surface coating and product finishing. Employed alloy powders are made by compounding two or more powders from mechanically crushed sendust, aerosolized sendust, aerosolized iron-silicon, aerosolized iron-nickel and aerosolized iron-nickel-molybdenum. The alloy powders complement each other in terms of performance so that the performance of the prepared composite powder core is close to that of a commercially available amorphous magnetic powder core. The prepared [mu]75 composite magnetic powder core has excellent physical properties and magnetic properties. In case of 100kHz, 1V, the effective magnetic permeability [mu]e of the magnetic powder core is 75; under 1000e, the coefficient of initial magnetic permeability is equal to or greater than 0.45; and the power loss PCV (50kHz, 1000Gs) of the magnetic powder core is equal to or smaller than 400mW / cm<3>. By use of the magnetic powder core prepared by the invention, the development requirements of an existing electronic industry for low-voltage high current, high power density and high frequency are greatly satisfied. Therefore, the prepared magnetic powder core can be applied to some occasions with quite high requirements for good stability and low cost as a replacement of a part of amorphous powder cores.

Description

technical field [0001] The invention relates to the field of soft magnetic materials and powder metallurgy, in particular to a method for manufacturing a μ75 composite magnetic powder core. This soft magnetic material is not only suitable for making high-current power inductors, PFC circuit inductors, DC / DC converters and photovoltaic inverters device etc. Background technique [0002] With the high frequency, miniaturization, and high power density of power electronic equipment, traditional silicon steel sheets are gradually losing their advantages, and iron-based magnetic powder cores are a relatively reasonable choice for cost performance. Among them, amorphous magnetic powder core is an ideal material combining power consumption advantages and DC superposition characteristics, but it has not been used in large quantities due to various reasons such as materials, powder core technology, and reliability. Traditional magnetic powder cores cannot balance loss, DC bias chara...

AI Technical Summary

Problems solved by technology

[0006] Step 2. Passivation: Due to the compounding of several alloy powders, each powder has different requirements for the passivation process. By adjusting the passivation process, anti-oxidation materials are added to the composite powder to solve the problem of different powder passivation process requirements. , the proportion of phosphating solution added is 0.1% to 1%, and diluted with 5% to 10% deionized water;