EBSD探测器Symmetry S3 牛津仪器

自20世纪80年代，增材制造（又称3D打印）作为一种新兴的先进成型技术开始出现。进入21世纪后，该技术逐渐成熟，开始应用在航空、汽车、医疗等领域，用于生产具有不规则曲面、深凹孔洞、细密内腔或者较大的厚薄比等特点的精密构件。增材制造用金属粉末的质检指标主要包括粉末的形态特征和杂质含量。牛津仪器纳米分析技术可对金属粉末的质检提供完善的解决方案。AZtecAM是基于牛津仪器EDS技术的颗粒物自动检测系统，用于大面积范围内金属粉末的形态统计和成分分析。AZtecAM根据设定的分类方法对采集到的颗粒进行即时分类。如果用户对某个颗粒感兴趣，AZtecAM可将该颗粒物二次定位，移动到电镜视场内，便于用户进行进一步的分析。

Introduction The groundbreaking Symmetry CMOS-based EBSD detector, together with the powerful AZtec® software, is capable of acquiring EBSD and EDS data at speeds in excess of 3000 indexed patterns per second (pps). These speeds, twice as fast as those achievable with conventional CCD-based detectors, are further enhanced by the fact that extreme pixel-binning of the diffraction patterns is not necessary. This means that the quality of the data collected using Symmetry is significantly better than with CCD-based detectors, both in terms of hit rate and also angular accuracy. In this application note we give examples of how Symmetry can be used to characterise the microstructures in two example metals at high speeds, providing reliable statistics in affordable timescales.

For many materials, the truly important is how they perform and behave under the conditions that they are likely to be exposed to during their use-lifetime. This may be the application of stresses and strains in construction materials, the dielectric properties of ceramics or the corrosion resistance of materials as they are exposed to a variety of atmospheric conditions.

Metals alloys and ceramics have a place in almost all of global manufacturing. Whether it is the turbine blades in a jet engine, the ceramic brake pads on a sports car or the steel cables for a suspension bridge, understanding the composition and structure of these materials is critical in understanding their properties.

The exploration of new metallic systems for high-temperature applications is an important challenge in today’s materials science.

Abstract. This study investigates the changes in radial micro-texture via Kearn’s f-factors during single cold pilger reduction of a titanium Ti-3-2.5 alloy as a result of strain path changes from tooling modifications. EBSD results confirm that the texture intensity as well as the radial f-factors can be increased by modifications of pilgering tooling. In addition a switch between the secondary prism planes which lie normal to the pilger direction in the starting tube to primary prism planes after pilgering has been observed. Material and Experimental The tubes investigated were made from Ti alloy 3Al 2.5V, they were manufactured via hot extrusion and then cold pilgered. The cold pilger process configuration is schematically shown in Figure 1. Two strain paths, shown in the ‘Q‘ factor chart in Figure 2, were used in the manufactiure: texture minimised and texture maximised. They were annealed at 750oC before being cold pilgered and for this investigation they were stress relieved at 530oC for 2 hours prior to EBSD examination. Specimens were extracted from two regions either side of the reduced tube as shown in the schematic Figure 2, mounted in conductive Bakelite and polished mechanically for EBSD examination. The final polish was carried out using vibratory polishes using a mixture of 5:2 colloidal silica, hydrogen peroxide mixture. EBSD examination was conducted using a FEGSEM and OI EBSD Nordlys detector and AZtec Software.

清洁能源技术是世界各国关注的热点，主要的发达国家都在大力推动电动汽车的发展，以期取代燃油车。电动汽车的发展离不开动力电池技术的进步，正极材料是动力电池的研究重点。寻找合适的成分体系一直是产业界和学术界的重要研究课题，相关的技术沿着降钴增镍、提高容量、稳定性和循环性能的方向发展。另外，有研究表明， 多晶正极材料的稳定性及循环性能不如单晶正极材料 [1]。国内多家企业将单晶正极材料作为自己的拳头产品，但多晶正极材料成本较低，仍然属于市场主流产品。优化结构以提高性能是多晶正极材料研究的重要方向。

在材料研究领域，温度一直是研究人员考虑的重要变量。随着显微分析设备的进步，目前的技术水平已经实现了电子显微镜内样品的高温原位分析，最高工作温度甚至可以超过 1000oC 。相较于室温分析，高温实验的最大挑战在于红外辐射的干扰。当样品加热超过 500oC ，红外辐射将会变得非常强烈，即使电镜腔室内没有其他照明光源，也可观察到高温样品发出的红外信号（如图 1 ）。这些红外辐射除了对电子图像的采集带来干扰，也对 EDS 和 EBSD 信号的采集带来极大的挑战。

Introduction The structure of natural shell samples has for many years been of significant interest, not only to researchers in the biological sciences, but also to material scientists [1]. This is primarily because the shells often have physical properties far exceeding those of their constituent minerals: in particular the mother of pearl structure, or “nacre”, consists of small, interlocking tablets of aragonite (orthorhombic CaCO3) separated by organic matrix membranes (Fig. 1).

Introduction Geological samples can be extremely challenging to analyse using EBSD, not only are they non-conductive, but many rocks contain a large number of phases, typically with low symmetry and often producing relatively weak diffraction patterns. The challenge is twofold: firstly the EBSD detector needs to be sensitive enough to acquire good, high resolution EBSPs in a short time period, and secondly the software needs to be able to distinguish reliably between all the minerals present in the sample. In this application we demonstrate the power of the Symmetry® CMOS-based detector coupled with the AZtec® software for the successful analysis of a multiphase, deformed eclogite sample. The extreme sensitivity of Symmetry enables high quality diffraction patterns to be collected in just a few milliseconds, and the advanced indexing algorithms within AZtec, as well as the full integration of EDS data, ensure reliable and accurate measurement of all phases.

Mineral liberation is a critical stage in the production of high quality mineralogical concentrates from their ores. The products (concentrates) must be of a suitable degree of purity for the downstream processes in which they will be used. The original mined ore must be processed via comminution (crushing, grinding and classification) to liberate the desired minerals from it and via concentration (froth flotation, gravity separation, magnetic separation) to enrich the mineral content to the desired level. In order to design, diagnose, monitor and optimise the process, information is needed on the extent to which the valuable mineral grains have been released from the accompanying gangue minerals (degree of liberation) and to which form they are lost in tailings (deportment studies).