Since there is a strong relation between the material characteristics and the crystal orientation of metals and many other industrial materials, quantitative analyses of crystallites orientation and their distributions are of great importance. Pole figure measurements are a common method to quantitatively analyze orientation. In this Application Byte, we used the Orientation Distribution Function (ODF) to evaluate the crystallites orientation of a Cu wiring film from a pole figure measurement.
Quantitative analysis by powder X-ray diffraction has long been carried out using calibration curves, a
technique that requires preparing samples whose components are quantified, using pure or standard
substances to obtain calibration curves. In recent years, quantitative analysis without calibration curves has
become possible by calculating quantitative values from crystal structures. However, these methods require
the crystal structures of the materials, limiting the applicable substances. With the Direct Derivation method
introduced here, the quantitative weight fractions of individual crystalline phases can be derived from sets of
integrated intensities collected in a wide 2 range, together with chemical composition data.
The Oido tunnel tombs in Wakuyacho, Miyagi (Japan) are tumuli that have been constructed between the late 7th century and the early 8th century. During scientific investigations between 1962 and 1964, a glass bead with a spotted pattern (concentric circles) rare to Japan was excavated, which is believed to be originated in South Asia or Southeast Asia. By evaluating the colored portion of the glass bead using the SmartLab Automated Multipurpose X-ray Diffractometer, it was possible to determine its chemical composition and provide a scientific basis for assumptions on the fabrication technique and a reevaluation of its origin. The research was conducted by the Nara National Research Institute for Cultural Properties in 2013, and presented at the 31st Congress of the Japan Society for Scientific Studies on Cultural Properties in 2014.
Thin films formed on substrates show various crystal phase and orientations depending on the materials and
manufacturing method. Therefore, phase identification is sometimes difficult by ordinary X-ray diffraction
(XRD) measurement. The diffraction image using a two-dimensional (2D) detector reveals the lattice constant
and the orientation for each crystal phase readily because the diffraction intensity distribution in the 2θ
direction and the distribution of the crystal orientation in the χ direction are observed simultaneously.
The crystal systems of pharmaceuticals and foods may change due to factors such as temperature and humidity. The
climate of Japan in particular exhibits extreme changes in temperature and humidity, with hot and humid summers, and dry, low-temperature winters, and these are poor conditions as an environment for synthesizing pharmaceuticals or storing foods. Therefore, there is a need to conduct measurement beforehand under various atmospheric conditions, and determine what sort of changes these materials undergo in the actual environment. Thus we evaluated thermal changes and changes in the crystal structure of pharmaceuticals by simultaneously measuring X-ray diffraction (XRD) and differential scanning calorimetry (DSC) while varying humidity.
In order to develop new materials that have desired properties, it is essential to evaluate the materials under
various atmospheric environments. The infrared heating high-temperature attachment Reactor X has a
corrosion-resistant sample chamber separated from the heater section, so it can be used to perform
high-temperature XRD measurements under various atmospheres, such as hydrogen, ammonia, high
humidity and so forth. Using Reactor X with a 2D detector capable of high-speed XRD measurement, it is
possible to investigate in detail rapid phase transitions under heating in various atmospheres.
In the tableting process for pharmaceuticals, it sometimes happens that the active pharmaceutical ingredient reacts with materials used as excipients, such as sugar or starch, and dehydration reactions, polymorph transitions and other processes may occur due to the pressure during tableting. In recent years, a need has arisen to check, in the shortest possible time, whether or not the active pharmaceutical ingredient maintains its original crystal system, and whether or not there are polymorph impurities. Furthermore, this must be done in the tableting process, while maintaining the tablet form. Therefore, we used a powder X-ray diffractometer to non-destructively measure the state of tablets in their original form, and evaluate the presence of the contained active pharmaceutical ingredient and polymorph impurities. By using a transmission-type parallel beam optical system, it is possible to obtain an accurate diffraction profile which does not depend on the sample form, and acquire information not only from the outside, but also from the inside of tablets. As a result of measurement, it was found that if polymorph impurities of the active pharmaceutical ingredient are about 1%, then their presence in the tablets could be confirmed in a measurement time of less than 10 minutes.
Carbide tools used for cutting are provided with various types of coatings to improve durability. Previously, evaluation of the coating layer has been done using X-ray diffraction, but some users want to achieve rapid and simultaneous evaluation of factors such as site-dependent differences in composition, crystallinity and orientation. These evaluations can be easily done by employing the optical element and detector used in this report.
Bulk samples such as metal blocks, ceramic sintered bodies, or pharmaceutical tablets are aggregates of
microcrystals that can be measured by powder X-ray diffraction. In conventional powder diffraction
measurements, samples need to be filled into a sample holder the size of a typical coin and placed in the
center of the diffractometer. Hence, to perform measurements of bulk samples, it has been necessary to cut
or pulverize samples according to the sample holder, or to use an attachment with an electrically driven
adjustment axis in the thickness direction of the sample. With Rigaku’s bulk sample holder, thick bulk samples
can be easily placed in the diffractometer without any need to cut or pulverize, making it possible to identify
crystal phases of bulk surfaces in a non-destructive manner.
Controlling the state of the charge-discharge process is believed to be crucial for extending the life of lithium ion batteries. Therefore, it is not enough to simply observe the electrode structure in the 100% charged and discharged states, and there is a need to carry out in-situ observation of the relationship between depth of charge, depth of discharge and electrode structure. However, if materials are removed once from sealed batteries, the materials will react with the atmosphere, and the charge-discharge state will change due to peeling of electrodes. Thus there is a risk of the material changing into another structure, irrespective of the charge-discharge situation. As a result, with previous methods, it was difficult to observe changes in materials accompanying charging-discharging via an X-ray diffraction measurement. However, with batteries made using lithium ion battery cells for evaluation and testing, X-ray diffraction can be performed simultaneously with charge-discharge testing. Thus it is possible to carry out evaluation by directly relating changes in the state of samples to charge-discharge characteristics, without performing any additional work on the materials subjected to charge-discharge testing, such as opening seals or peeling electrodes.