摘要本文用真空电弧炉制备了NiMnInCo合金，并利用差示扫描量热仪(DSC)、振动样品磁强计(VSM)及X射线衍射仪等对合金试样的马氏体转变、相结构以及合金的磁性能进行了研究。阐明了不同球磨工艺与退火参数对Ni-Mn-In基合金相变和磁性能的影响规律。68056

    研究结果表明：

   （1）确定球磨后样品成分为Ni47.35Mn37.71In12.43Co4.68Fe1.43，高能球磨和低能球磨后的样品在退火过程中会发生两个结构转变，分别为面心四方到体心立方转变和体心立方到L21结构的转变。

   （2）高能球磨与低能球磨后的样品退火后的相组成为马氏体和奥氏体的混合相。而且随着退火温度的增加，马氏体含量增加。

   （3）晶粒尺寸过小会抑制球磨退火后的样品粉末发生马氏体相变。球磨退火后的Ni47.35Mn37.71In12.43Co4.68Fe1.43粉末马氏体相变温度比块体高。     

   （4）退火使得因为球磨时产生的空位和缺陷得到有序化处理，晶格发生了重组，Mn-Mn之间的铁磁耦合作用增强，所以高能球磨与低能球磨样品在退火后的饱和磁化强度较退火前有显著提升，且一定温度范围内随着退火温度的升高而增加。

毕业论文关键词  Ni-Mn-In合金；马氏体相变；结构转变；饱和磁化强度

毕业设计说明书（论文）外文摘要

Title：Structure, phase transition and magnetic properties of ball-milled Ni-Mn-X based Heusler alloy powders

Abstract：

NiMnInCo alloys were melted by vacuum arc furnace. The transformation of martensitic alloys, phase structure and the magnetic property of alloys were studied with differential scanning calorimetry calorimeter (DSC), vibration sample magnetic field meter (VSM) and X-ray diffraction (XRD). The influence of ball milling on phase composition, phase transformation and magnetic properties are illuminated.

The results show that:

1  The composition of the ball milled powder is Ni47.35Mn37.71In12.43Co4.68Fe1.43. The vibration ball milled powders will occur two structure transitions with fcc to disorder bcc and bcc to L21 during annealing process.

2  The ball milled powders are mixed phase with austenitic phase and martensitic phase after annealing.And with the increase of annealing temperature, martensite content increased.

3  The undersize of grains will suppress phase transformation of powder after annealing. The temperature of martensitic transformation in ball milled powder is higher than in block.

4  Saturation magnetization of the ball milled powder increases dramatically after annealing, and it increases with annealing temperature in a range of temperature. 

Keywords:  Ni-Mn-In alloys; Martensitic transformation; Structure transition; Saturation magnetization

目   次

1  绪论 1

1.1  磁控形状记忆合金的发展概况 1

1.2  Heusler合金和Ni-Mn-In合金简介 2

1.3  球磨Ni-Mn-In合金的研究现状 4

1.5  选题目的与研究内容 8

2  实验方法 9

2.1  实验合金制备 9

2.2  实验研究方法 10

3  NiMnInCo合金的结构 13

3.1  高能球磨与低能球磨的结构变化 13

3.2  NiMnInCo合金的能谱图谱分析