【摘要】：Fe-6.5%Si合金磁粉芯由于具有高的飽和磁感應(yīng)強(qiáng)度、優(yōu)異的直流疊加特性和相對(duì)較低的成本,被廣泛的應(yīng)用于高頻電路。本文結(jié)合鐵硅磁粉芯產(chǎn)品應(yīng)用的性能指標(biāo)需求和企業(yè)規(guī)模生產(chǎn)工藝特點(diǎn),考察了形貌、粒度配比、絕緣包覆、壓制成型以及熱處理工藝對(duì)磁粉芯有效磁導(dǎo)率、直流疊加性能和單位體積功耗的影響,并利用典型有效磁導(dǎo)率金屬磁粉芯進(jìn)行了單端正激電路扼流圈的應(yīng)用設(shè)計(jì)研究,取得的主要研究結(jié)果如下:相對(duì)于機(jī)械破碎法制備的鐵硅合金粉末,氣霧化Fe-6.5%Si粉末具有較高的飽和磁化強(qiáng)度和較低的矯頑力等優(yōu)點(diǎn),相同制備工藝條件下制備的磁芯具有更低的損耗和更好的直流疊加特性。合金粉末的顆粒尺寸減小,磁粉芯樣品的有效磁導(dǎo)率相應(yīng)地降低、品質(zhì)因數(shù)明顯增大,其直流疊加性能也相應(yīng)地得到改善。設(shè)計(jì)的改性硅溶膠包覆工藝能有效改善合金粉末的表面包覆效果;且包覆液用量增加,磁粉芯樣品的有效磁導(dǎo)率相應(yīng)地降低、直流疊加性能提高,但損耗表現(xiàn)出先減小再增大的趨勢(shì);當(dāng)包覆液用量為1.0 wt%時(shí),樣品的恒定磁導(dǎo)率為78,50kHz、500Gs條件下的功耗為189mW/cm3,直流疊加場(chǎng)為100Oe時(shí)磁導(dǎo)率百分比為55%。成型壓力在1287Mpa~1931Mpa范圍內(nèi)與鐵硅磁粉芯的密度成正比,增大成型壓力可以提高鐵硅磁粉芯的有效磁導(dǎo)率,同時(shí)降低磁芯的損耗。在氮?dú)鈿夥铡?20℃~540℃熱處理?xiàng)l件下,有效磁導(dǎo)率隨溫度升高先增大后減小,在500℃時(shí)具有相對(duì)較高的有效磁導(dǎo)率并表現(xiàn)出良好的頻率恒定特性,同時(shí)直流疊加性能、Q值與磁芯損耗也表現(xiàn)最佳。利用多次包覆工藝可在合金粉末表面形成復(fù)合結(jié)構(gòu)包覆層,使鐵硅磁粉芯的性能得到進(jìn)一步優(yōu)化,即磁芯的有效磁導(dǎo)率為57,損耗為186.44mW/mm3,直流疊加場(chǎng)為10 Gs時(shí)磁導(dǎo)率百分比為73.57%。應(yīng)用設(shè)計(jì)方面,獲得了單端正激電路扼流圈的金屬磁粉芯規(guī)格、繞線參數(shù)等。
[Abstract]:Fe-6.5%Si alloy powder cores are widely used in high frequency circuits due to their high saturation magnetic induction strength, excellent DC superposition characteristics and relatively low cost. In this paper, the effective permeability of ferrosilicon magnetic core was investigated by combining with the requirement of performance index and the characteristics of enterprise scale production technology, such as morphology, particle size ratio, insulation coating, compaction molding and heat treatment, etc. The effect of DC superposition performance and power consumption per unit volume is studied, and the application design of single terminal forward circuit choke is studied by using typical effective permeability metal magnetic powder core. The main results obtained are as follows: compared with the Fe-Si alloy powder prepared by mechanical crushing, the gas-atomized Fe-6.5%Si powder has the advantages of high saturation magnetization and low coercivity. The core prepared under the same preparation process has lower loss and better DC superposition characteristics. The particle size of the alloy powder decreases, the effective permeability of the magnetic powder core decreases correspondingly, the quality factor increases obviously, and its DC superposition property is improved accordingly. The modified silica sol coating process can effectively improve the surface coating effect of the alloy powder, and the effective permeability of the magnetic powder core sample decreases correspondingly, and the DC superposition property increases with the increase of the amount of the coating liquid. When the amount of coating liquid is 1.0 wt%, the constant permeability of the sample is 189mW / cm ~ (3) under the condition of 78g / 50kHz / 500Gs, and the percentage of permeability of the sample is 55mm / cm ~ (-3) when the DC superposition field is 100Oe. The forming pressure is proportional to the density of iron-silicon magnetic powder core in the range of 1287Mpa~1931Mpa. Increasing the forming pressure can increase the effective permeability of iron silicon magnetic powder core and reduce the loss of the core at the same time. Under the condition of heat treatment at 420 鈩，

本文編號(hào)：2151225