CN113481420A - 一种铁磁金属材料及其制备方法和应用 - Google Patents

一种铁磁金属材料及其制备方法和应用 Download PDF

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CN113481420A
CN113481420A CN202110785655.4A CN202110785655A CN113481420A CN 113481420 A CN113481420 A CN 113481420A CN 202110785655 A CN202110785655 A CN 202110785655A CN 113481420 A CN113481420 A CN 113481420A
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段磊
靳常青
望贤成
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Henan University of Technology
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • B22F9/00Making metallic powder or suspensions thereof
    • B22F9/02Making metallic powder or suspensions thereof using physical processes
    • B22F9/04Making metallic powder or suspensions thereof using physical processes starting from solid material, e.g. by crushing, grinding or milling
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Abstract

一种铁磁金属材料,该铁磁金属材料的化学式为La3MnAs5,晶体结构为六方晶系,空间群为P63/mcm,对应空间群号为193,所述铁磁金属材料的晶体结构沿着c轴方向由三聚化的MnAs6八面体通过面共享方式连接,呈一维链状结构;ab平面由MnAs6链组成三角晶格,链与链之间平行排列,链间的距离为晶格常数a。该铁磁金属材料通过以下方法制备得到:先将金属La粉末、金属Mn粉末和As粉末按照3:1:5摩尔比例充分研磨混合,再利用压片机将研磨后的混合物压制成形,最后在3~8GPa压力以及1200~1400℃下烧结获得所述铁磁金属材料。本发明的铁磁金属材料具有典型的一维晶体结构,具有较高的磁转变温度,磁各向异性特征较好。

Description

一种铁磁金属材料及其制备方法和应用
技术领域
本发明属于材料技术领域,具体涉及一种铁磁金属材料及其制备方法和应用。
背景技术
铁磁金属材料作为一类重要的基础功能材料,目前已被广泛地应用于电子、自动化、通信、医疗及生活用品等诸多领域,同时,铁磁材料在信息的存储、处理与传输等方面也扮演着重要的作用。因此,作为一种优良的高密度磁记录材料、电磁波吸收材料、生物和医学工程材料,铁磁金属材料得到了广大科研工作者的广泛研究和关注。
一维自旋链系统由于维度的降低而展现出有别于二维或三维系统的新奇物理特性如超导、强的磁各向异性、量子相变等等,一直以来都是凝聚态物理领域研究的热点。同时,一维自旋链系统可以作为理解更复杂的高维系统的磁性一个很好的起点。然而在实际中,理想的一维材料是不存在的。一维自旋链在堆积的过程中,不可避免地会出现耦合作用,从而形成准一维自旋链材料。准一维自旋链材料尤其是铁磁性材料因为其独特的晶体结构以及磁各向异性等物性,可以突破各向同性铁磁材料对电磁性能的限制,为开发新型的电磁功能材料开辟新的途径。
目前研究较多的准一维自旋链铁磁材料在输运方面均展现出绝缘体行为,并且自旋链之间的电子跃迁较弱,使得其铁磁长程序温度均比较低,这些大大限制了它们在自旋电子器件方面的应用,因此开发新型的具有高磁转变温度的准一维自旋链铁磁具有重要意义。
发明内容
本发明的目的在于提供一种铁磁金属材料及其制备方法和应用,该铁磁金属材料具有典型的一维晶体结构,具有较高的磁转变温度,磁各向异性特征较好。
本发明为实现上述目的所采用的技术方案是:
一种铁磁金属材料,该铁磁金属材料的化学式为La3MnAs5,晶体结构为六方晶系,空间群为P63/mcm,对应空间群号为193,所述铁磁金属材料的晶体结构沿着c轴方向由三聚化的MnAs6八面体通过面共享方式连接,呈一维链状结构;ab平面由MnAs6 链组成三角晶格,链与链之间平行排列,链间的距离为晶格常数a。
一种铁磁金属材料的制备方法,其特征在于,包括以下步骤:
(1) 将金属La粉末、金属Mn粉末和As粉末按照3:1:5摩尔比例研磨混合,得到混合物;
(2) 利用压片机将步骤(1)得到的混合物压制成形;
(3) 将经步骤(2)压制成形的混合物在3~8GPa压力以及1200~1400℃温度条件下进行烧结,即得所述铁磁金属材料。
进一步地,步骤(2)中混合物经压制成形得到圆柱体。
进一步地,所述圆柱体的直径为6mm,高为1~3mm。
进一步地,步骤(3)中烧结的时间为0.1~3小时。
如上所述的铁磁金属材料在制备电磁器件方面的应用。
本发明的有益效果:
本发明首次采用高温高压方法,制备出新型的准一维自旋链铁磁金属材料La3MnAs5,属于六方晶系,空间群为P63/mcm(No.193),该铁磁金属材料具有典型的一维晶体结构,Mn链之间较大距离保证了理想的一维性,展现出很好的磁各向异性特征,在电磁器件制备等方面具有潜在的应用前景。此外,本发明的铁磁金属材料La3MnAs5也是一个理想的巡游铁磁材料,为调控量子临界点、探索非常规超导体等提供了很好的材料基础。
附图说明
以下,结合附图来详细说明本发明的实施方案,其中:
图1是本发明实施例1-7所得La3MnAs5材料的X射线衍射图;
图2是本发明实施例1-7所得La3MnAs5材料的磁性测试结果,图中,T表示温度;
图3是本发明实施例1-7所得La3MnAs5材料的电阻测试结果;
图4是本发明实施例1-7所得La3MnAs5材料的比热测试结果。
具体实施方式
为了使本发明的目的、技术方案及优点更加清楚明白,以下结合实施例,对本发明进行进一步详细说明。应当理解,此处所描述的具体实施例仅仅用以解释本发明,并不用于限定本发明。
实施例1
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比为3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将研磨混合得到的混合物在压片机下压成直径为6mm,高度为3mm的圆柱体,然后将得到的圆柱体放入高压合成组装块中,在5 GPa压力、1300℃温度下进行高温高压烧结,烧结时间为0.5h,烧结产物自然冷却至室温后得铁磁金属材料A。
实施例2
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为3mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在4 GPa压力、1200℃温度下进行高温高压烧结,烧结时间为1h,烧结产物自然冷却至室温后得到铁磁金属材料B。
实施例3
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为3mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在6 GPa压力、1400℃温度下进行高温高压烧结,烧结时间为0.5h,烧结产物自然冷却至室温后得到铁磁金属材料C。
实施例4
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为1mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在2GPa压力、1200℃温度下进行高温高压烧结,烧结时间为2h,烧结产物自然冷却至室温后得到铁磁金属材料D。
实施例5
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为3mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在8 GPa压力、1200℃温度下进行高温高压烧结,烧结时间为0.5h,烧结产物自然冷却至室温后得到铁磁金属材料E。
实施例6
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为2mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在5 GPa压力、1200℃温度下进行高温高压烧结,烧结时间为10min,烧结产物自然冷却至室温后得到铁磁金属材料F。
实施例7
以高纯的La粉、Mn粉以及As粉作为原料,按照La:Mn::As摩尔比3:1:5准确称量三者,并充分均匀研磨混合得到混合物,利用模具将混合均匀的粉末在压片机下压成直径6mm,高度为3mm的圆柱,然后将得到的圆柱放入高压合成组装块中,在5 GPa压力、1200℃温度下进行高温高压烧结,烧结时间为3h,烧结产物自然冷却至室温后得到铁磁金属材料G。
对上述7个实施例得到的铁磁金属材料A、铁磁金属材料B、铁磁金属材料C、铁磁金属材料D、铁磁金属材料E、铁磁金属材料F以及铁磁金属材料G的样品分别进行X射线衍射图谱分析、磁性、电阻及比热测定,结果均呈现如图1-4所示,其中,图1为测定所得铁磁金属材料样品的X射线衍射图谱,图2为磁性测定结果,图3为电阻测定结果,图4为比热测定结果,结果表明,所得铁磁金属材料样品均为单相,化学式为La3MnAs5,晶体结构为六方晶系,空间群为P63/mcm,对应空间群号为193,其晶体结构沿着c轴方向由三聚化的MnAs6八面体通过面共享方式连接,呈典型一维链状结构,而ab平面是由这些MnAs6 链组成三角晶格,链之间的距离为晶格常数a,具有明显的一维特征,其晶格参数为a=8.9913(1) Å, c=5.9416(1)Å,按照其结构精修得到的晶格参数a值足够大,进一步确定其为一维结构;铁磁居里温度为109.7K,磁性测试显示样品在109.7K时出现顺磁到铁磁转变,电阻测试表明,样品为金属,并在109.7K处有明显变化,比热测试在109.7K也有明显的变化,电阻和比热测试都再次确认为铁磁转变。
需要说明的是,上述实施例仅用来说明本发明,但本发明并不局限于上述实施例,凡是依据本发明的技术实质对以上实施例所作的任何简单修改、等同变化与修饰,均落入本发明的保护范围内。

Claims (6)

1.一种铁磁金属材料,其特征在于,该铁磁金属材料的化学式为La3MnAs5,晶体结构为六方晶系,空间群为P63/mcm,对应空间群号为193,所述铁磁金属材料的晶体结构沿着c轴方向由三聚化的MnAs6八面体通过面共享方式连接,呈一维链状结构;ab平面由MnAs6 链组成三角晶格,链与链之间平行排列,链间的距离为晶格常数a。
2.如权利要求1所述的一种铁磁金属材料的制备方法,其特征在于,包括以下步骤:
(1) 将金属La粉末、金属Mn粉末和As粉末按照3:1:5的摩尔比例研磨混合,得到混合物;
(2) 利用压片机将步骤(1)得到的混合物压制成形;
(3) 将经步骤(2)压制成形的混合物在3~8GPa压力以及1200~1400℃温度条件下进行烧结,即得所述铁磁金属材料。
3.如权利要求2所述的一种铁磁金属材料的制备方法,其特征在于,步骤(2)中混合物经压制成形得到圆柱体。
4.如权利要求3所述的一种铁磁金属材料的制备方法,其特征在于,所述圆柱体的直径为6mm,高为1~3mm。
5.如权利要求2所述的一种铁磁金属材料的制备方法,其特征在于,步骤(3)中烧结的时间为0.1~3小时。
6.如权利要求1所述的一种铁磁金属材料在制备电磁器件方面的应用。
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