CN112466591A - 一种低温度系数的镍锌铁氧体及其制备方法与应用 - Google Patents
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Abstract
本发明属于软磁铁氧体技术领域,具体公开了一种低温度系数的镍锌铁氧体及其制备方法与应用。所述低温度系数的镍锌铁氧体,包括主成分和副成分,其中主成分包括以下组分:Fe2O3 47~50mol%、NiO 13~20mol%、ZnO 25~35mol%、CuO 5~7mol%;所述副成分包含氧化锡。本发明采用合理之主配方,以NiO与ZnO之含量比例来调整材料的导磁率,而以Fe2O3含量来控制高温区的温度系数以及居里温度,CuO的含量用以控制烧结温度以及居里温度;在副成分中加入SnO2以控制整体的温度系数;再透过制程工艺调整铁氧体的烧结活性,从而得到具有低温度系数的镍锌铁氧体材料。
Description
技术领域
本发明属于软磁铁氧体技术领域,特别涉及一种低温度系数的镍锌铁氧体及其制备方法与应用。
背景技术
工业上的软磁铁氧体用于电磁之间的储能转换,为被动组件中不可或缺的部件,除用于计算器、通讯、电源或消费性电子产品等领域,也于车用电子部件占有重要之地位,而车用产品首先讲究安全与稳定,所以需求的各项材质特性中,关于温度稳定性的要求日趋严格。
车用产品在外在环境以及内部安装位置的影响下,工作温度可能有从摄氏零下到破百度的变化。在需求的温度区间内,要求铁氧体材料导磁率的变化程度要越小越好,才能提供组件稳定的运作表现。
发明内容
为了克服上述现有技术的缺点与不足,本发明的首要目的在于提供一种低温度系数的镍锌铁氧体。
本发明另一目的在于提供一种制备上述低温度系数的镍锌铁氧体的方法
本发明再一目的在于提供上述低温度系数的镍锌铁氧体在滤波电感器中的应用。
本发明的目的通过下述方案实现:
一种低温度系数的镍锌铁氧体,包括主成分和副成分,其中主成分以标准分子量计包括以下组分:Fe2O3 47~50mol%、NiO 13~20mol%、ZnO 25~35mol%、CuO 5~7mol%;所述副成分包含氧化锡,相对主成分之总量,其以标准分子量计的含量如下:SnO20.2~0.5wt%。
优选地,相对于主成份总量,所述副成份以标准分子量计的含量为:SnO20.4wt%。
一种制备低温度系数的镍锌铁氧体的方法,包括以下步骤:
A、混合:按主成份配比以原材料进行干式混合;
B、煅烧:将混合完毕的材料置于容器内进行预烧得到煅烧料;
C、粉碎研磨:将所得煅烧料搭配副成份材料混合均匀,以温式球磨的方式进行粉碎研磨得到浆料;
D、造粒:将步骤C的浆料加入PVA(聚乙烯醇),采用喷雾造粒法得到颗粒材料;
E、成型:将步骤D的颗粒材料压制成型得到生胚;
F、烧结:将步骤E压制完成的生胚进行烧结,得到磁环样品。
步骤B中所述预烧为在850±10℃,煅烧420~540分钟。
步骤C所述研磨优选为以湿式球磨的方法进行,研磨时间为60~90分钟;研磨完成后所得浆料粒径应控制在1.0~1.8μm。所述研磨的球体介质为钢珠,大小为1/8~3/4英寸,优选为1/4英寸。
步骤D所述PVA的添加量为主成分原料总重的1.5~3.2wt%;
步骤E所得生胚的密度为3.4±0.2g/cm3。
步骤F所述烧结的温度为106~110℃,烧结时间为120~150分钟,烧结气氛为空气。
上述低温度系数的镍锌铁氧体在滤波电感器中的应用。
本发明相对于现有技术,具有如下的优点及有益效果:
本发明采用合理之主配方,以NiO与ZnO之含量比例来调整材料的导磁率,而以Fe2O3含量来控制高温区的温度系数以及居里温度,CuO的含量用以控制烧结温度以及居里温度;在副成分中加入SnO2以控制整体的温度系数;再透过制程工艺调整铁氧体的烧结活性,从而得到具有低温度系数的镍锌铁氧体材料。本发明制备方法所得到之制品具有良好的烧结密度5.1±0.2g/cm3。本材料适用于车用电子产品的AEC规范。材料的具体特性指标如下:初始导磁率μi:800±25%;居里温度Tc:≧160℃;相对温度系数αF(-40℃~25℃):-3~3;相对温度系数αF(25℃~150℃):-3~3。
附图说明
图1为实施例2和对比例1的宽温对比图。
图2为本发明所得实际产品图。
具体实施方式
下面结合实施例和附图对本发明作进一步详细的描述,但本发明的实施方式不限于此。
实施例中所用试剂如无特殊说明均可从市场常规购得。
PVA的聚合度为400~1800。
实施例中低温度系数镍锌铁氧体采用氧化物法制造,具体步骤依序如下:
A、混合:按主成分配比以原材料进行干式混合,混合时间为75分钟;
B、煅烧:将混合完毕之材料置于容器内以推板炉进行预烧,煅烧温度控制在850±10℃,煅烧时间为480分钟;
C、粉碎研磨:将煅烧完毕之煅烧料搭配前述之副成分材料一起投入搅磨机中,以湿式球磨的方式进行粉碎研磨,研磨之球体介质为1/4英寸之钢珠,研磨时间为60~90分钟之间,研磨完成之浆料粒径应控制在1.0~1.8μm;
D、造粒:将步骤C的浆料加入相当于主成分原料总重2.0wt%的PVA(聚乙烯醇),采用喷雾造粒法得到颗粒材;
E、成型:将步骤D的颗粒材以粉末干压成型机压制得到生胚,生胚的密度应控制在3.4±0.2g/cm3;
F、烧结:将步骤E压制完成的生胚以烧结炉进行烧结,烧结温度控制在1060~1100℃之间,持温时间为120~150分钟,烧结气氛为空气,烧结结束后,空冷随炉降至室温。通过以上工序得到的镍锌铁氧体制品为外径20mm、内径12mm而厚度10mm之磁环样品(T20*12*10)。
表1为实施例1-3以及对比例1-4主成分和副成分的配比
将T20*12*10之磁环样品进行测试。以0.25mm线径之铜线缠绕磁环样品10圈,用HP-4294A型LCR测试仪测试磁环之初始导磁率μi;搭配TMJ-9712B可控式恒温恒湿箱,测试磁环的居里温度Tc;搭配TMJ-9712B可控式恒温恒湿箱,用HP-4263B型LCR测试仪测试样品于-40~150℃之间每5℃一个区间的初始导磁率μi,透过公式得到相对温度系数αF。具体结果如表2所示。
表2实施例1-3和对比例1-4的性能比较
注1.超过规格上限的以※符号表示,低于规格下限的以*符号表示。
注2.在居里温度Tc的数值栏中,≧160℃代表其居里温度至少大于160℃。
从表2可以看出,本发明的实施范例相较于对比例,有效的降低了相对温度系数αF,且还能保持相近之初始导磁率,居里温度(Tc)亦都能满足规格。
从图1中可以看出,具有相似的初始导磁率之对比例1与实施例2,对比例之温度相对温度系数大,因此初始导磁率随温度的升降幅也非常大,在150℃时已接近2000,而实施范例仅在700~800之间,与室温相比几乎没有波动。
搭配表1亦可以看出,控制氧化铁的含量降低,改善了对比例2~4从25~150℃的相对温度系数;而氧化锡的加入则进一步再降低了整体的相对温度系数,达到实施范例1~3的低相对温度系数之效果。本发明之镍锌铁氧体材料应能满足车用滤波器对于温度特性之需求。
上述实施例为本发明较佳的实施方式,但本发明的实施方式并不受上述实施例的限制,其他的任何未背离本发明的精神实质与原理下所作的改变、修饰、替代、组合、简化,均应为等效的置换方式,都包含在本发明的保护范围之内。
Claims (10)
1.一种低温度系数的镍锌铁氧体,其特征在于包括主成分和副成分,其中主成分以标准分子量计包括以下组分:Fe2O3 47~50mol%、NiO 13~20mol%、ZnO 25~35mol%、CuO 5~7mol%;所述副成分包含氧化锡,相对主成分之总量,其以标准分子量计的含量如下:SnO2 0.2~0.5wt%。
2.根据权利要求1所述的低温度系数的镍锌铁氧体,其特征在于:相对于主成份总量,所述副成份以标准分子量计的含量为:SnO2 0.4wt%。
3.一种制备权利要求1或2所述低温度系数的镍锌铁氧体的方法,其特征在于包括以下步骤:
A、混合:按主成份配比以原材料进行干式混合;
B、煅烧:将混合完毕的材料置于容器内进行预烧得到煅烧料;
C、粉碎研磨:将所得煅烧料搭配副成份材料混合均匀,以温式球磨的方式进行粉碎研磨得到浆料;
D、造粒:将步骤C的浆料加入聚乙烯醇,采用喷雾造粒法得到颗粒材料;
E、成型:将步骤D的颗粒材料压制成型得到生胚;
F、烧结:将步骤E压制完成的生胚进行烧结,得到磁环样品。
4.根据权利要求3所述的方法,其特征在于:步骤B中所述预烧为在850±10℃,煅烧420~540分钟。
5.根据权利要求3所述的方法,其特征在于:步骤C所述研磨为以湿式球磨的方法进行;研磨时间为60~90分钟。
6.根据权利要求5所述的方法,其特征在于:步骤C所述研磨完后所得浆料的粒径为1.0~1.8μm。
7.根据权利要求3所述的方法,其特征在于:步骤D所述聚乙烯醇的添加量为主成分原料总重的1.5~3.2wt%。
8.根据权利要求3所述的方法,其特征在于:步骤E所得生胚的密度为3.4±0.2g/cm3。
9.根据权利要求3所述的方法,其特征在于:步骤F所述烧结的温度为106~110℃,烧结时间为120~150分钟,烧结气氛为空气。
10.根据权利要求1或2所述低温度系数的镍锌铁氧体在滤波电感器中的应用。
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US20100321140A1 (en) * | 2007-02-07 | 2010-12-23 | Hitachi Metals, Ltd. | Low-loss ferrite and electronic device formed by such ferrite |
US20100085140A1 (en) * | 2007-04-17 | 2010-04-08 | Hitachi Metals, Ltd. | Low-loss ferrite and electronic device formed by such ferrite |
CN108314440A (zh) * | 2018-01-22 | 2018-07-24 | 天通控股股份有限公司 | 一种宽频宽温低温度因数高强度镍锌铁氧体及其制备方法 |
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