EBSD技术及其在取向硅钢研究中的作用

电子背散射衍射EBSD是一种用来分析多晶材料显微结构、晶粒取向和微观织构的扫描电镜新技术。本文结合基本原理介绍了EBSD技术在取向硅钢研究中的作用。     

EBSD分析技术在ECAP变形材料研究中的应用

简述了电子背散射衍射(EBSD)技术的基本原理和试验分析方法,并结合实例说明EBSD技术在等径弯曲通道变形(ECAP)材料取向、晶界研究等方面的应用。     

NdFeB烧结磁体矫顽力变化同取向度关系

日本日立集团北井伸幸等人用电子背散射衍射法（EBSD）测量烧结NdFeB磁体晶粒取向度,以这些取向度分布计算矫顽力变化率同取向度关系,以此计算结果与磁性测量结果进行比较。EBSD测定发现,本研究所用磁体取向分布接近高斯分布定则,如取向磁场相同,含Dy和不含Dy磁体之间取向度分布无差异。     

AZ31镁合金EBSD试样的制备方法

提出了一种AZ31镁合金电子背散射衍射(EBSD)试样制备方法,合理的电解工艺参数:直流电源电压为15～20 V,电解电流强度为0.1～0.5 A,电解温度为-30～-40 ℃,电解时间为120~200 s.试验结果表明,在对AZ31镁合金试样进行EBSD分析菊池带质量和晶粒取向图时,取向标定率可达到95%以上.而采用传统的制样方法,其取向标定率为85%.此外,新的EBSD试样制备方法具有实用且费用低的优点,试验成本仅为传统方法的1%.     

热处理温度对TC21钛合金微观组织的影响

对TC21钛合金在880～950℃进行固溶,研究了固溶温度对TC21钛合金的微观组织的影响规律.采用OM、TEM及EBSD取向分析方法,研究了热处理温度对TC21钛合金中形成块状α相的影响规律.结果表明,在880℃、900℃观察到了块状α相,在930℃、950℃没有观察到块状α相.EBSD取向分析表明,大块α相与其临近β相之间满足Burgers取向关系.显微硬度在900℃固溶后达最小值,温度高于900℃时,显微硬度增加.     

氢含量对再结晶Zr-Sn-Nb管材氢化物微观结构及取向的影响

虽然已有较多锆合金氢化物的研究,但对于较高氢含量中锆合金氢化物的研究较少。首先对Zr-Sn-Nb管材在400℃下气相渗氢,通过保温不同时间获得三种不同氢含量（147、340、1480 ppm）的渗氢样品。随后采用OM、SEM、TEM和EBSD表征技术,研究了Zr-Sn-Nb管材中氢化物的微观结构、与基体的晶体学取向关系。结果表明：氢含量影响管材中氢化物的取向,α-Zr基体与氢化物之间存在(0001)α∥{111}δ和{10-17}α∥{111}δ两种取向关系。EBSD分析表明氢化物从一个基体晶粒生长向另一个基体晶粒时取向会随着基体晶粒取向的变化而变化。部分锆基体晶粒内同时有晶内氢化物和晶间氢化物,而只有晶内氢化物与锆基体有晶体学取向关系。     

冷轧板再结晶退火中组织和织构演变的研究

薄板坯连铸连轧(CSP)热轧板料经热处理来适当调整组织后进行冷轧及退火,并运用电子背散射衍射(EBSD)技术研究了再结晶退火中组织和织构的演变.结果表明:发生再结晶的温度范围是530℃～590℃,590℃为完全再结晶温度;再结晶发生时冷轧变形基体和新晶粒取向的晶界角度差大约为25°～55°;{111}〈110〉、{111}〈112〉取向在再结晶初期和中期发生很大的变化,而{001}〈110〉、{112}〈110〉取向在再结晶后期才发生很大的变化;EBSD检测的结果分析可得{001}〈110〉、{112}〈110〉、{111}面取向储存的变形能依次增加.     

基于CSP工艺Fe-3％Si钢初次再结晶退火的晶界特征

以实验室模拟CSP工艺生产的Fe-3％ Si钢为研究对象,采用XRD、EBSD技术研究了取向硅钢初次再结晶晶粒的取向和晶界结构.结果表明,初次再结晶晶粒中,高斯晶粒在数量上并不占优,优势取向为γ取向.高斯晶粒主要出现在{111} <112>取向晶粒周围,且高斯晶粒周围的晶界类型以25°～55°的大角度晶界和∑3晶界为主.     

纳米压痕法研究单晶Al3Sc相的硬度和杨氏模量

使用EBSD和纳米压痕法研究毫米级块状单晶Al₃Sc对应的取向、硬度和杨氏模量。试验结果表明,选用过共晶Al-Sc合金加热至液态后缓慢冷却(60 ℃/h)可以得到毫米级单晶Al₃Sc,通过EBSD和纳米压痕法得到五个不同取向(567)、(139)、(124)、(113)和(144)单晶Al₃Sc的硬度在3.7~4.3 GPa,复合弹性响应模量在143.6~146.1 GPa。对比不同泊松比下各取向的杨氏模量理论值与试验值,发现泊松比为0.188时二者之间差异最小,对应各取向的杨氏模量试验值在157.5~160.6 GPa。     

600MPa级冷轧高强钢性能及组织研究

介绍了600MPa级冷成型用冷轧高强度汽车钢板的成分设计、冶炼、轧制工艺,并且优化了实验室连续退火工艺;用金相显微镜、电子背散射EBSD、SEM以及TEM观察了高强钢组织的宏观与微观结构和取向,讨论了过时效温度对钢板力学性能和组织的影响。结果表明,过时效温度为400℃时,钢板具有良好的综合力学性能;C-Mn-Si-Nb系冷轧高强钢拥有高的强度和好的伸长率,其组织主要由板条贝氏体和铁素体两相组成;EBSD技术分析得出晶粒间多为大角度晶界,有一半以上的晶粒都是{111}//Z型取向。     

Oriented crystallization of thin Pd-Cu films

The phase composition, substructure, and orientation of thin Pd-Cu films obtained by magnetron sputtering of an alloy target and condensation on the (001) surface of phlogopite have been studied by transmission electron microscopy (TEM). Three-orientation epitaxial structures of the β phase with a CsCl structure have been obtained. In epitaxial two-phase solid-solution films, the α and β phases are oriented according to the Nishiyama-Wassermann and Kurdjumov-Sachs orientation relationships. Single-crystal films of α and β solid solutions have been obtained on phlogopite. The plasma effect has been revealed; under the conditions of magnetron sputtering the orientation relationships not typical of epitaxial films of fcc and bcc metals on phlogopite have been realized in the temperature-concentration range of the β ? α phase transformation.     

A Detailed Observation on Successive Stress-Induced Martensite Transformation in CuAlMnZnZr Alloy Polycrystalline Above Af

The successive stress-induced martensite morphologies and mechanisms in polycrystalline CuA1MnZnZr samples have been examined. By applying stress to the uniform β１ matrix, two or more orientation plates of M18R martensite are stress-induced in a grain. With further increasing stress, one orientation plate depletes the other and coalesces into a single region in some view field. The mechanisms by which these are developed have been ascertained, and include variant-variant coalescence, stress-induced martensite to martensite transformation and the complicated cross-like stress-induced martensite formation.     

超磁致伸缩复合材料的静态弹性模量及抗压强度

采用粘结技术制备出了性能良好的磁致伸缩复合材料，着重研究了合金含量、粉末粒度、磁场取向、粉末表面处理对样品的静态弹性模量及抗雎强度的影响规律。结果表明，粉末粒度、粉末表面处理对复合材料的抗压强度及静态弹性模量均有较大的影响；合金含量、磁场取向对复合材料的静态弹性模量影响不大，其中合金含量对复合材料的抗压强度有较大的影响。     

Texture transformations upon annealing of aluminum foils: I. Strong texture components

Pole figures have been constructed and textures have been compared for aluminum foils from various manufacturers in the as-delivered state and after additional annealings. Difference in the orientations of the basic texture components have been revealed in annealed foils. The main type of the transformation of a texture upon annealing is the development of a texture component {001}〈100〉 whose orientation differs fundamentally from the basic texture components observed in the foil prior to annealing. In another type of texture transformations, new texture components close to the basic orientations of the deformation texture are developed along with the {001}〈100〉 orientation. In the case of a third type of texture transformations, along with the orientation {001}〈100〉 which is formed upon recrystallization, the major part of the basic deformation-texture components are retained. The orientations of the basic texture components that are formed upon annealing belong to fields of allowed orientations of the basic texture components that were present in the foil before annealing. Apart from regions with a high pole density, regions with a moderate pole density have been found in the pole figures of annealed foils.     

单晶Nb拉伸,压缩及恒应变疲劳后的滑移系和滑移特征

研究了单滑移位向和多滑移位向Ｎｂ单晶在拉伸，压缩及循环变形时的滑移系，根据试样表面滑移线的方向，在极图上确定滑移面，单滑移位向（［３２１］）的单晶，在拉伸时的滑移系为（１０１）［１１１］，在压缩时是（１０１）［１１１］和（２１３）［１１１］．根据ｂｃｃ晶体变形特点，分析了拉伸，压缩和循环变形的滑移系之间的关系，用光学显微镜和透射电镜复型观察了试样的表面形貌，确定了多滑移位向（［１１０］位向）单晶滑     

高温超导YBCO的定向凝固

讨论了YBCO高温超导体定向凝固中所涉及的包晶反应、界面稳定性及其形态控制、凝固取向和晶向控制等问题。并提出了定向凝固中应该注意的问题。     

ROLES OF ORIENTATION RELATIONSHIP AND RECRYSTALLIZATION IN SUPERPLASTICITY OF SiCw/6061Al COMPOSITE

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Electron-microscopic examination of microstructural changes in structural martensitic steel after low-cyclic fatigue tests

Microstructural changes in a structural martensitic steel upon low-cyclic fatigue (LCF) deformation have been investigated. The micromechanics of plastic deformation and accompanying effects have been studied at the scale of martensite laths and packets with the aid of transmission electron microscopy (TEM). It has been shown that with increasing LCF deformation, changes in both the morphology and the internal structure of martensite occur. The changes are manifested in the form of a refinement of the structural units of martensite. It has been revealed that in the limits of a packet the fatigue deformation occurs inhomogeneously. However, the laths of the same orientation are deformed equally and almost simultaneously. The influence of the dimensions of former austenite grains and orientation of packets on the LCF process has been considered. The mechanics of the fatigue plastic deformation on the nano-, meso-, and microlevels and the processes that accompany this deformation have been studied.     

The influence of crystallographic orientation distribution on 316LVM stainless steel pitting behavior

In this research, the influence of crystallographic orientation on pitting corrosion susceptibility of 316LVM stainless steel surface has been investigated using orientation imaging microscopy (OIM) technique. It has been shown that the susceptibility of the surface to pitting corrosion depends strongly on the crystallographic orientation of the planes parallel to the surface. This has revealed an anisotropic nature of pitting initiation on the surface, suggesting that controlling the texture of the material can be considered as a means of ameliorating the material’s pitting resistance. The generalized spherical harmonic functions have been used to express the pitting susceptibility of various crystallographic planes. Using the proposed formula and the texture inverse pole figure of the investigated material (obtained from orientation distribution function, ODF), the pitting susceptibility index (PSI) of the surface is predicted based on texture measurements. The results obtained thus demonstrate a novel method of improving pitting resistance of SS316LVM by designing the desired texture.     

三维可调绞链联接板连续冲压工艺及模具设计

介绍了三维可调门铰链上的联接板的冲压工艺分析。对模具结构形式,定位、定向、定距方式,卸料、出件方式,导向方式等设计内容进行了阐述。该模具提高了材料利用率和生产效率,保证了工件的尺寸、位置精度。