摘要:烧结钕铁硼材料由于具有较高的剩磁、矫顽力和磁性能而日益受到广泛的应用。鉴于高温热等静压烧结通常对加速合金致密化及控制晶粒长大有突出作用,为了提高钕铁硼磁体的使用温度、磁性能和耐腐蚀性,本次实验研究了热等静压对烧结钕铁硼的影响。实验通过排水法测量磁体的密度;金相显微镜观察钕铁硼的微观组织结构,比较晶粒的大小和均匀性;采用ATM-4永磁测量仪测量钕铁硼的磁性能;并采用电化学方法测量磁体的电化学极化曲线,研究热等静压对钕铁硼耐腐蚀性的影响。通过研究热等静压烧结对Nd-Fe-B磁体的致密度、显微组织及磁性能的影响;结果表明与常压烧结磁体相比, 热等静压烧结磁体的晶粒尺寸和密度增加,孔隙率和取向度下降,磁体的耐腐蚀性得到提高,但提高的幅度比较小。综合研究结果表明通过加热氩气产生的热等静压不适合制造高性能的钕铁硼烧结磁体。关键词:热等静压;钕铁硼;致密度;取向度;耐腐蚀性9209
毕业设计说明书(论文)外文摘要
Title :Influence of Cladless Hot Isostatic Pressing on Magnetic Properties and Corrosion Resistance of Sintered NdFeB Magnets
Abstract
NdFeB material was increasingly wide used because of a high remanence, coercivity and magnetic. In view of the high temperature hot isostatic pressing and sintering have a prominent role in the alloy densification and controlling the grain, in order to improve the use temperature of NdFeB magnets, the magnetic properties and corrosion resistance, the experimental make study of the hot isostatic pressing impact on sintered NdFeB. The experiment measure the density of the magnet experiment by the method of drainage; use metallographic microscope observation of the microstructure of Nd-Fe-B in order to comparison of grain size and uniformity; using the ATM-4 PM measuring instrument measuring NdFeB magnetic; measuring electrochemical polarization curve of the magnet by the method of electrochemical, research hot isostatic pressing on the corrosion resistance of Nd-Fe-B. Through the study of sintered Nd-Fe-B magnets density, microstructure and magnetic properties after hot isostatic pressing; The results showed that compared with the atmospheric pressure sintered magnet, not only the grain size and density, porosity and degree of orientation decreased, the corrosion resistance of the magnet also improved. The results show that the heat generated by heating argon isostatic not suitable for the manufacture Nd-Fe-B sintered magnets of high performance.
Keywords: Hot isostatic pressing; NdFeB; Density; Orientation degree; Corrosion resistance
目 录
1 引言 1
1.1 热等静压技术 1
1.2 永磁材料 5
1.3 烧结钕铁硼永磁材料的磁参量及其物理意义 7
1.4 本课题的研究背景和研究内容 10
2 实验方法及过程 11
2.1 实验材料 11
2.2 实验设备 11
2.3 实验方法 12
3 实验结果及分析 15
3.1 对磁体致密度的影响 15
3.2 对磁体显微组织的影响 15
3.3 对磁体取向度的影响 17
3.4 对磁体磁性的影响 18
3.5 对磁体耐腐蚀性的影响 21
结 论 24
致 谢 25
参 考 文 献 261 引言
1.1 热等静压技术
1.1.1 热等静压技术的基本介绍
热等静压(HIP-Hot Isostatic Pressing)工艺是一种以氮气、氩气等惰性气体为传压介质,将制品放置到密闭的容器中,在700~2000℃温度和100~200MPa压力的共同作用下,向制品施加各向同等的压力,对制品进行压制烧结处理的技术。 热等静压对烧结钕铁硼磁体的影响研究:http://www.751com.cn/cailiao/lunwen_7843.html