CN111243814A - 一种铜片内嵌式软磁粉芯电感及其制备方法和用途 - Google Patents
一种铜片内嵌式软磁粉芯电感及其制备方法和用途 Download PDFInfo
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Abstract
本发明涉及一种铜片内嵌式软磁粉芯电感及其制备方法和用途,所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料;所述铜片内嵌式软磁粉芯电感具有密度高、磁芯磁导率高、电感量高、饱和磁通密度高、体积小及漏磁少的特点,将其替代同样感量的铁氧体电感应用于低压DC/DC转化器电路中,其能获得一致或者更高的效率,同时电感体积减小可达一半以上,本发明所述铜片内嵌式软磁粉芯电感的耐压可达15V以上,且本发明所述铜片内嵌式软磁粉芯电感的制备方法简单,生产效率高,适于大规模自动化生产。
Description
技术领域
本发明属于电子技术领域,涉及一种铜片内嵌式软磁粉芯电感及其制备方法和用途。
背景技术
近年来,随着半导体器件的高速化发展,电感器的需求朝着高效率、低感量、小型化、大电流化演变。随之而来,对软磁材料的要求是,低损耗、高磁导率以及高饱和磁通密度。目前,常见的电感包括一体成型电感和铁氧体电感。
其中,一体成型电感将金属磁性粉末和树脂混合炼制,然后与金属线圈一体成型制得电感器,其具有可应对大电流,同时实现小型化的优点,但由于其压制压力小、金属粉末占有体积比小等劣势,使得其与铁氧体电感器相比,很难获得高磁导率,从而难以达到所需的电感量,必须采用增加线圈的方式来提高感量,导致电感DCR较大,铜损较大。而铁氧体电感虽磁导率高,但饱和磁通密度小,需要开气隙防止饱和,从而导致漏磁等相关问题的出现,在使用过程中容易出现局部温升高、回路效率低的不良现象;此外,铁氧体电感的体积较大也成为限制其应用的关键因素之一。
CN107768069A公开了一种电感器及其制作方法,电感器的制作方法包括以下步骤:S1,制作磁芯,采用造粒磁粉压制成高密度块体,然后切削成磁芯结构,并且烧结致密;所述磁芯包括中柱和两个叶摆;S2,线圈绕制:将线圈绕制在所述中柱上,绕制后使得线圈的截面平行于所述电感器的长高平面,且线圈的两个引出端位于中柱的两侧,且处于同一平面上;S3,模压成型:在模具底部填一层所述造粒磁粉进行预压致密,然后将步骤S2中绕有线圈的磁芯植入模具中;植入后在模具内填满所述造粒磁粉进行模压成型;S4,半成品热处理;S5,端电极制作;此方案所得电感存在压制压力小、热处理温度低导致的产品电感量低、磁通密度小、损耗大的问题。
CN107275045A公开了一种电感的制作方法、及其塑封材料的制备方法,其中其塑封材料的制备方法包括将重量百分比为60%~90%的粉料与重量百分比为10%~40%的环氧树脂均匀混合,再将混合的物料压制成团状物料,置于-5~0℃环境下冷藏,即为电感的塑封材料,其中粉料为镍锌铁氧体粉料、锰锌铁氧体粉料、铁硅铬粉料、铁硅铝粉料中的一种或几种;电感的制作方法,包括将绕好漆包铜线的磁芯焊接连接在引线框上,再采用前述塑封材料进行注塑封装,制作得到电感,此方案所得电感存在软磁粉末比重小、成型压力小导致的电感磁通密度小、损耗大的问题。
因此,开发一种饱和磁通密度高、电感量高、体积小,且适用于低压DC/DC转换器电路中具有高效率的电感仍具有重要意义。
发明内容
本发明的目的在于提供一种铜片内嵌式软磁粉芯电感及其制备方法和用途,所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料;所述铜片内嵌式软磁粉芯电感具有密度高、磁芯磁导率高、电感量高、饱和磁通密度高、体积小及漏磁少的特点,将其替代同样感量的铁氧体电感应用于低压DC/DC转化器电路中,其能获得一致或更高的效率,同时电感体积减小可达一半以上,本发明所述铜片内嵌式软磁粉芯电感的耐压可达15V以上,且本发明所述铜片内嵌式软磁粉芯电感的制备方法简单,生成效率高,适于大规模自动化生产。
为达到此发明目的,本发明采用以下技术方案:
第一方面,本发明提供了一种铜片内嵌式软磁粉芯电感,所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料。
本发明所述铜片内嵌式软磁粉芯电感具有高的饱和磁通密度,可对应大电流(30A-100A),大幅缩小电感体积,同时不会出现因开气隙导致的漏磁问题。
本发明所述铜片内嵌式软磁粉芯电感具有电感量高的特点,与传统一体电感相比,可减少绕线圈数,缩小电感体积并降低电感损耗。仅使用一层铜片就可以达到铁氧体电感相同水平的电感量。
优选地,所述铜片的两端未被软磁材料覆盖,所述两端为任意相对的两端。
优选地,所述铜片的长宽比为8:1~10:1,例如8.5:1、9:1或9.5:1等。
优选地,所述绝缘树脂材料包括有机硅树脂材料。
优选地,所述软磁材料由金属软磁粉末压制成型得到。
优选地,所述压制成型的压力为12-18T/cm2,例如13T/cm2、14T/cm2、15T/cm2、16T/cm2或17T/cm2等。
优选地,所述铜片内嵌式软磁粉芯电感中软磁材料的密度为5.5~6.5g/cm3,例如5.6g/cm3、5.7g/cm3、5.8g/cm3、5.9g/cm3、6.1g/cm3或6.3g/cm3等。
相较于传统铁氧体电感,本发明所述铜片内嵌式软磁粉芯电感具有更高的密度及饱和磁通密度,从而使得所述铜片内嵌式软磁粉芯电感可以应对更大电流,并缩小体积50%以上。
优选地,所述软磁材料在铜片两侧表面的覆盖区域相互对称。
优选地,所述软磁材料在铜片的两侧表面上对称分布。
此处所述对称分布指的是位于铜片两侧表面的软磁材料的长度、宽度和厚度完全相同,且覆盖区域也以铜片为对称平面相互对称。
优选地,所述金属软磁粉末包括铁粉、铁硅粉、铁硅铝粉、铁镍粉或铁镍钼粉中的任意一种或至少两种的组合,所述组合示例性的包括铁粉和铁硅粉的组合或铁硅铝粉、铁镍粉和铁镍钼粉的组合等。
第二方面,本发明提供了如第一方面所述的铜片内嵌式软磁粉芯电感的制备方法,所述方法包括以下步骤:
(1)在铜片表面涂覆绝缘树脂材料、烘烤、固化;
(2)将步骤(1)中得到的涂覆有绝缘树脂材料的铜片置于金属软磁粉末中,压制成型,惰性气氛下退火,得到所述铜片内嵌式软磁粉芯电感。
本发明所述铜片内嵌式软磁粉芯电感的制备过程首先在铜片表面涂覆绝缘树脂材料,之后在金属软磁粉末中压制成型,退火;得到所述铜片内嵌式软磁粉芯电感,其中,采用压制成型的方法能有效提高制备得到的电感的密度及磁性材料的体积比,进而提高制备得到的铜片内嵌式软磁粉芯电感的磁导率及电感量,减少绕线圈数,节省铜损。且铜片内置金属软磁粉体内进行压制,有助于减小电感体积、减少漏磁。
本发明所述方法将铜片内置在金属软磁粉体内,之后压制成型,其制备过程简单,有利于提高生产效率,适于大规模自动化生产。
优选地,步骤(1)所述绝缘树脂材料包括有机硅树脂材料。
优选地,步骤(2)所述金属软磁粉末包括铁粉、铁硅粉、铁硅铝粉、铁镍粉或铁镍钼粉中的任意一种或至少两种的组合;所述组合示例性的包括铁粉和铁硅粉的组合或铁硅铝粉、铁镍粉和铁镍钼粉的组合等。
优选地,步骤(2)所述金属软磁粉末的平均粒径为2-25μm,例如5μm、8μm、10μm、15μm、20μm或25μm等。
优选地,步骤(2)所述压制成型的压力为12-18T/cm2,例如13T/cm2、14T/cm2、15T/cm2、16T/cm2或17T/cm2等。
优选地,步骤(2)所述退火的温度为550-700℃,例如580℃、600℃、620℃、650℃或680℃等。
优选地,步骤(2)所述退火的时间为1-3h,例如1.5h、2h或2.5h等。
优选地,所述惰性气氛为氮气。
作为本发明优选的技术方案,所述铜片内嵌式软磁粉芯电感的制备方法包括以下步骤:
(1)在铜片表面涂覆有机硅树脂材料、烘烤、固化;
(2)将步骤(1)中得到的涂覆有有机硅树脂材料的铜片置于平均粒径为10μm的金属软磁粉末中,在压力为12~18T/cm2的条件下压制成型,得到成型体,之后将其置于退火炉中,惰性气氛下550-700℃退火1-3h,得到所述铜片内嵌式软磁粉芯电感。
第三方面,本发明提供了如第一方面所述的铜片内嵌式软磁粉芯电感的用途,所述铜片内嵌式软磁粉芯电感用于低压DC/DC转换器电路。
相对于现有技术,本发明具有以下有益效果:
(1)本发明所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料,其与传统铁氧体电感相比,其具有磁通密度高、体积小、且不会因开气隙导致漏磁的优势;
(2)本发明所述铜片内嵌式软磁粉芯电感应用于低压DC/DC转换器电路中,与传统铁氧体电感相比,其可以获得一致或更高的效率,且体积减小可达一半以上,且其耐压可达15V以上;
(3)本发明所述铜片内嵌式软磁粉芯电感的制备方法简单,可明显提高生产效率,适于大规模自动化生产。
附图说明
图1是本发明所述铜片内嵌式软磁粉芯电感的结构示意图。
具体实施方式
下面通过具体实施方式来进一步说明本发明的技术方案。本领域技术人员应该明了,所述实施例仅仅是帮助理解本发明,不应视为对本发明的具体限制。
具体实施方式部分所述铜片内嵌式软磁粉芯电感的结构示意图如图1所示,由图1可以看出,所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料;所述软材材料在铜片的两侧表面对称分布,所述铜片的两端未被软磁材料覆盖,如图1所示,铜片上未被软磁材料覆盖的区域进行如图所示的弯曲。
实施例1
铜片内嵌式软磁粉芯电感的制备方法:
(2)将经步骤(1)处理后的铜片埋置于铁硅铝磁性粉末内,粉末平均粒径15μm,以16T/cm2压力压制成型,得到成形体,所述成形体长14mm,宽5mm,高2mm;之后,将成形体置于退火炉中,在氮气气氛下,经过680℃退火120分钟,得到铜片内嵌式软磁粉芯电感。
所述成形体的尺寸包含软磁材料的尺寸及位于软磁材料内部的铜片的尺寸。
实施例2
铜片内嵌式软磁粉芯电感的制备方法:
(2)将经步骤(1)处理后的铜片埋置于铁硅铝磁性粉末内,粉末平均粒径15μm,以12T/cm2压力压制成型,得到成形体,所述成形体长14mm,宽5mm,高2mm;之后,将成形体置于退火炉中,在氮气气氛下,经过680℃退火120分钟,得到铜片内嵌式软磁粉芯电感。
实施例3
铜片内嵌式软磁粉芯电感的制备方法:
(2)将经步骤(1)处理后的铜片埋置于铁硅铝磁性粉末内,粉末平均粒径10μm,以18T/cm2压力压制成型,得到成形体,所述成形体长14mm,宽5mm,高2mm;之后,将成形体置于退火炉中,在氮气气氛下,经过680℃退火120分钟,得到铜片内嵌式软磁粉芯电感。
实施例4
本实施例与实施例1的区别在于,将退火温度由680℃替换为550℃,其他条件与实施例1相比完全相同。
实施例5
本实施例与实施例1的区别在于,将退火温度由680℃替换为450℃,其他条件与实施例1相比完全相同。
实施例6
本实施例与实施例1的区别在于,将退火温度由680℃替换为800℃,其他条件与实施例1相比完全相同。
实施例7
本实施例与实施例1的区别在于,将步骤(2)中的铁硅铝磁性粉末的平均粒径由10μm替换为2μm,其他条件与实施例1相比完全相同。
实施例8
本实施例与实施例1的区别在于,将步骤(2)中的铁硅铝磁性粉末的平均粒径由10μm替换为20μm,其他条件与实施例1相比完全相同。
实施例9
本实施例与实施例1的区别在于,将步骤(2)中的铁硅铝磁性粉末替换为等平均粒径的铁镍粉,其他条件与实施例1相比完全相同。
实施例10
本实施例与实施例1的区别在于,将步骤(2)中的铁硅铝磁性粉末替换为等平均粒径的铁镍钼粉,其他条件与实施例1相比完全相同。
对比例1
本对比例采用与实施例1中同样感量的铁氧体电感,所述铁氧体电感的尺寸为长14mm,宽5mm,高8mm;其制备方法如下:制作带凹槽14mm×5mm×4mm铁氧体两片,凹槽深1.7mm,将两片铁氧体上下对扣,铜片从凹槽穿过并折弯,成为所需铁氧体电感。
性能测试:
测试实施例1-10制备得到的铜片内嵌式软磁粉芯电感和对比例1所述铁氧体电感的密度、体积和感量,并将其应用于低压DC/DC转换器电路中,测试其效率值;其测试结果如表1所示;此处铜片内嵌式软磁粉芯电感的体积指的是成形体的体积和未被软磁材料覆盖的铜片的体积之和。
其中,应用于低压DC/DC转换器电路中的测试条件为:频率700kHz,电流40A,电压1V;
测试实施例1-10制备得到的铜片内嵌式软磁粉芯电感和对比例1所述铁氧体电感的绝缘耐压,其测试结果如表1所示。
表1
由上表可以看出,本发明所述铜片内嵌式软磁粉芯电感的密度在5.5-6.5g/cm3之间,其密度明显高于对比例1中的铁氧体电感;且对比实施例1和对比例1可以看出,在感量相同的条件下实施例1中的铜片内嵌式软磁粉芯电感的体积为对比例1中铁氧体电感体积的约四分之一,且实施例1中的铜片内嵌式软磁粉芯电感应用于低压DC/DC转换器电路中的效率略高于对比例1中所述铁氧体电感。
由实施例1、4-6对比可以看出,退火温度为550-680℃时,所得铜片内嵌式软磁粉芯电感应用于低压DC/DC转换器电路中的效率更高。
申请人声明,以上所述仅为本发明的具体实施方式,但本发明的保护范围并不局限于此,所属技术领域的技术人员应该明了,任何属于本技术领域的技术人员在本发明揭露的技术范围内,可轻易想到的变化或替换,均落在本发明的保护范围和公开范围之内。
Claims (10)
1.一种铜片内嵌式软磁粉芯电感,其特征在于,所述铜片内嵌式软磁粉芯电感包括铜片,所述铜片的表面覆盖有软磁材料,所述软磁材料与所述铜片的界面处含有绝缘树脂材料。
2.如权利要求1所述的铜片内嵌式软磁粉芯电感,其特征在于,所述绝缘树脂材料包括有机硅树脂材料。
3.如权利要求1或2所述的铜片内嵌式软磁粉芯电感,其特征在于,所述软磁材料由金属软磁粉末压制成型得到;
优选地,所述金属软磁粉末包括铁粉、铁硅粉、铁硅铝粉、铁镍粉或铁镍钼粉中的任意一种或至少两种的组合;
优选地,所述铜片内嵌式软磁粉芯电感中软磁材料的密度为5.5~6.5g/cm3。
4.如权利要求1-3任一项所述的铜片内嵌式软磁粉芯电感的制备方法,其特征在于,所述方法包括以下步骤:
(1)在铜片表面涂覆绝缘树脂材料、烘烤、固化;
(2)将步骤(1)中得到的涂覆有绝缘树脂材料的铜片置于金属软磁粉末中,压制成型,惰性气氛下退火,得到所述铜片内嵌式软磁粉芯电感。
5.如权利要求4所述的方法,其特征在于,步骤(1)所述绝缘树脂材料包括有机硅树脂材料;
优选地,步骤(2)所述金属软磁粉末包括铁粉、铁硅粉、铁硅铝粉、铁镍粉或铁镍钼粉中的任意一种或至少两种的组合;
优选地,步骤(2)所述金属软磁粉末的平均粒径为2-25μm。
6.如权利要求4或5所述的方法,其特征在于,步骤(2)所述压制成型的压力为12-18T/cm2。
7.如权利要求4-6任一项所述的方法,其特征在于,步骤(2)所述退火的温度为550-700℃;
优选地,步骤(2)所述退火的时间为1-3h。
8.如权利要求4-7任一项所述的方法,其特征在于,所述惰性气氛为氮气。
9.如权利要求4-8任一项所述的方法,其特征在于,所述方法包括以下步骤:
(1)在铜片表面涂覆有机硅树脂材料、烘烤、固化;
(2)将步骤(1)中得到的涂覆有有机硅树脂材料的铜片置于平均粒径为10μm的金属软磁粉末中,在压力为12~18T/cm2的条件下压制成型,得到成型体,之后将其置于退火炉中,惰性气氛下550-700℃退火1-3h,得到所述铜片内嵌式软磁粉芯电感。
10.如权利要求1-3任一项所述的铜片内嵌式软磁粉芯电感的用途,其特征在于,所述铜片内嵌式软磁粉芯电感用于低压DC/DC转换器电路。
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