In materials science or applied crystallography, X-ray diffraction represents a versatile and useful method with which one can obtain the orientation of single crystals or even the texture of a polycrystalline material. When the investigated sample consists of many phases, or phases of low symmetry, it becomes difficult to measure pole figures from single diffraction peaks. A combined Rietveld–texture analysis with the program MAUD is perfectly suitable to deal with conditions of overlapping diffraction peaks, including those arising from different phases. Even though nearly no alternative to MAUD exists, it is not always easy to use. The input of a file series of two-dimensional diffraction images, for example from a texture measurement, can be time consuming since each individual image must be loaded manually, and only the newest beta version of MAUD allows semi-automated file input. The new program input4MAUD , which is presented in this paper, offers a much more efficient way to automate both single and batch file series input into MAUD as well as the preparation of basic batch refinements with MAUD. input4MAUD is written in Visual C++ and is currently available as a 32-bit statically compiled binary executable file for Windows.

Objective. A major aspect in evaluating the quality of dental materials is their physical properties. Their properties should be a best fit of the ones of dental hard tissues. Manufacturers give data sheets for each material. The properties listed are characterized by a specific value. This assumes (but does not prove) that there is no direction dependence of the properties. However, dental enamel has direction-dependent properties which additionally vary with location in the tooth. The aim of this paper is to show the local direction dependence of physical properties like the elastic modulus or the thermal expansion in dental hard tissues. With this knowledge the 'perfect filling/dental material' could be characterized. Materials and method. Enamel sections of similar to 400-500 mu m thickness have been cut with a diamond saw from labial/buccal to palatal/lingual (canine, premolar and molar) and parallel to labial (incisor). Crystallite arrangements have been measured in over 400 data points on all types of teeth with x-ray scattering techniques, known from materials science. Results. X-ray scattering measurements show impressively that dental enamel has a strong direction dependence of its physical properties which also varies with location within the tooth. Dental materials possess only little or no property direction dependence. Therefore, a mismatch was found between enamel and dental materials properties. Conclusion. Since dental materials should possess equal (direction depending) properties, worthwhile properties could be characterized by transferring the directional properties of enamel into a property 'wish list' which future dental materials should fulfil. Hereby the 'perfect dental material' can be characterized.

Dental enamel is the most highly mineralised and hardest biological tissue in human body [16]. It is made of hydroxylapatite (HAP) Ca5(PO4)3(OH), which is hexagonal (6/m). The lattice parameters are a = b = 9.418 Å and c = 6.875 Å. About the inner structure of dental enamel it’s known, that it is composed of elongated “enamel prisms” of about 20μm diameter [1]. The crystallographic structure, respectively the orientation of the HAP-crystals in the prisms has not been investigated in detail up to now [2-4]. It is known, that the prisms penetrate through the enamel undisturbed from the dentine to the surface [1,5]. Structural built-up information about the prisms like the often described feather-like spreading [6] originate from light optical and electron microscopy descriptions about 160 respectively 50 years ago [7-10]. Thereby the real spatial orientation of the crystallites can differ in contrast to these shape based observations. The exact crystallographic orientation of the crystallites within the prisms has not been described. In this study, the spatial orientation of of the HAP crystallites was determined using X-ray texture analysis. The method is described in detail elsewhere [11]. Source of the X-ray beam was the wiggler BW5 at the synchrotron DORIS, Hamburg, Germany. A monochromatic beam with a wavelength of 0.12155 A°and a rectangular size of 500 μm x 500 μm was used. The textures have been examined in more then 150 local positions within all kind of teeth. For each position 33 diffraction images at different orientation angles were taken. The images were evaluated with the program MAUD [12] finally providing information of the orientation g of the lattice planes (h k l). Exemplary the data for molar tooth 11 and incisor tooth 17 (FDI Notation) is shown here (cf. Fig 1). All data points from other teeth show comparable trends, supporting the results presented here. For interpreting textures of human dental enamel, it is sufficient to look at the (0 0 1) pole figures which likewise show the orientation of the c-axis of the unit cell, since the present texture type originates from a free rotation around the normal of the tilted (0 0 1) crystal planes [13-15].

Niobium micro-alloyed high strength low alloy (HSLA) steels are widely used in civil construction, automobile and line pipe applications. These steels rely on thermo-mechanical rolling, a technique that simultaneously provides high strength and toughness by grain refinement. Since these steels typically contain low carbon contents, they also have excellent welding and cold forming properties. The most important role of niobium as a micro-alloying element in thermo-mechanically rolled steel is the retardation of austenite recrystallization, which provides more nuclei for the γ/α transformation and thus a finer grain size. Besides niobium’s role in solid solution by delaying all diffusion controlled processes, its tendency to form carbides provides the dominant effect [3, 4]. HSLA-Steels contain either the elements niobium, vanadium and titanium or a combination of them. Premature precipitation of Nb(C, N) in the secondary cooling section of the continuous caster may trigger hot embrittlement and transverse cracking. Furthermore Niobium has to remain in solid solution in order to make optimum use of its metallurgical potential during thermo-mechanical hot rolling. This is of particular importance in a coupled casting and direct hot rolling process. Depending on the hot rolling parameters, such as deformation amount and rate, temperature and interpass time, niobium carbide precipitation is generally incomplete with regard to the thermodynamic equilibrium state. As a result, a part of the niobium stays in solid solution after finish rolling in the austenite phase and is effective in retarding the transformation or allowing a strength increase by precipitation hardening in the ferrite phase [4]. The niobium in solid solution at the finish-rolling temperature is available for the formation of fine niobium carbo-nitride precipitates in ferrite. These are of the appropriate size for providing a strength increase via precipitation hardening. In accelerated cooled and tempered steel specimens some investigations did not reveal any evidence that additional precipitation in the ferrite occurred. Precipitation in ferrite was only found after subsequent cold deforming and tempering of the considered samples [3, 4]. Hence, the occurrence of precipitation depends strongly of the deformation, the cooling conditions and the chemical composition of the steel. It is the main intention of these investigations to identify the possible formation process of niobium carbides or other precipitations. It can be assumed that the orientation distribution of the niobium carbide precipitates is not random, because of the strong texture of the Fe-matrix. This could be a reason for anisotropic mechanical behavior.

Knowing the elastic modulus of human dental enamel is of high importance since dental filling materials should posses equal mechanical properties as enamel itself. If this demand is not fulfilled, the interaction between filling and enamel is not equivalent, so that healthy enamel could be simply abrased during chewing. Hence it is astonishing that the literature shows a big variety of suggestions for the elastic modulus. This paper will give a short overview about some existing results (maybe not all) and tries to compare and evaluate them. The experiments have been done too, trying to make it more easy for the experienced reader to make up his own mind about the elastic modulus of human dental enamel.

Obtaining information about the intrinsic structure of polycrystalline materials is of prime importance owing to the anisotropic behaviour of individual crystallites. Grain orientation and its statistical distribution, i.e. the texture, have an important influence on the material properties. Crystallographic orientations play an important role in all kinds of polycrystalline materials such as metallic, geological and biological. Using synchrotron diffraction techniques the texture can be measured with high local and angular resolving power. Here methods are presented which allow the spatial orientation of the crystallites to be determined and information about the anisotropy of mechanical properties, such as elastic modulus or thermal expansion, to obtained. The methods are adapted to all crystal and several sample symmetries as well as to different phases, for example with overlapping diffraction peaks. To demonstrate the abilities of the methods, human dental enamel has been chosen, showing even overlapping diffraction peaks. Likewise it is of special interest to learn more about the orientation and anisotropic properties of dental enamel, since only basic information is available up to now. The texture of enamel has been found to be a tilted fibre texture of high strength (up to 12.5×). The calculated elastic modulus is up to 155 GPa and the thermal expansion up to 22.3 × 10(-6)°C(-1).

The knowledge about the orientation of the prisms in human dental enamel is mainly based on morphological observations (light optical, SEM, etc.). Hence there are many schematic drawings, showing the orientation as seen in the microscope. Locally resolved direct measurements of the orientations, proofing the observations, have not been done in detail up to now. X-ray diffraction methods adapted from material science are used in this study, providing directly the orientation of the crystallites in the examined positions. Hereby new and better detailed information was obtained, showing the orientation of the prisms and giving information about their intrinsic structure. Based on the measurements, existing prism orientation models can be enhanced and two structural suggestions can be made, showing possible inner building principles for the prisms. Future planned measurements will even allow deciding which of the two models is more likely.

The exoskeleton of the crustacean Homarus americanus, the American lobster, is a biological multiphase composite consisting of a crystalline organic matrix (chitin), crystalline biominerals (calcite), amorphous calcium carbonate and proteins. One special structural aspect is the occurrence of pronounced crystallographic orientations and resulting directional anisotropic mechanical properties. The crystallographic textures of chitin and calcite have been measured by wide-angle Bragg diffraction, calculating the Orientation Distribution Function (ODF) from pole figures by using the series expansion method according to Bunge. A general strong relationship can be established between the crystallographic and the resulting mechanical and physical properties.

Dental enamel is the most highly mineralized and ha rdest biological tissue in human body [1]. The mineral which the dental enamel is almost made of i s hydroxylapatite (HAP) Ca5(PO4)3(OH), which occurs in prisms. Although HAP is the hardest mineral, it can be dissolved easily in a process, which is known as enamel demineralization by lactic acid produced by bacteria. In addition, the direct consumption of acid (e.g. citr i , lactic or phosphoric acid in soft drinks) can harm the dental enamel in a similar way. When these processes go on too long, the damage of the dental enamel can be so big that it is dissolved co mpletely and a cavity occurs. At this point, the health of the tooth is in serious danger cause now the dental pulp and the nerve can be also affected by the caries. The best would be to go to the denti st, so that the cavity could be cleaned and filled. The materials for a dental filling vary a lot. It c ould be gold, amalgam, ceramics or plastic material . When the filling is made, the danger for the health of the tooth is repelled. However, in the progress there can occur other dangers in direct combination with the filling. The mechanical properties of the materials used to fill cavities differ signific ant from the ones of the dental enamel. In the wors t case, the filling of a tooth can damage the enamel of the opposite tooth, hence by chewing the interaction of enamel and filling is not equivalent , so that the harder filling can abrase the softer enamel of the healthy tooth at the opposite side. T his could be avoided if the mechanical properties of dental enamel would be known in detail, hence th n another filling could be searched or fabricated as an equivalent opponent for the dental en mel with equal properties. To find such a material, one has to characterize the properties of dental enamel first in detail, e.g. to get the anisotropic elastic modulus of human enamel. This c ould be done by texture analysis, hence a general strong relationship exists between crystall ographic and morphological textures and the resulting mechanical and functional anisotropy of c rystalline materials [2]. So far, the accurate arrangement of the HAP-crystals in the dental ename l is not known, only described as "highly complex" [1]. First results of the texture analysis for selected teeth are shown here.

Dental enamel is the most highly mineralised and hardest biological tissue in human body [1]. Dental enamel is made of hydroxylapatite (HAP) - Ca5(PO4)3(OH), which is hexagonal (6/m). The lattice parameters are a = b = 0.9418 nm und c = 0.6875 nm [1]. Although HAP is a very hard mineral, it can be dissolved easily in a process which is known as enamel demineralization by lactic acid produced by bacteria. Also the direct consumption of acid (e.g. citric, lactic or phosphoric acid in soft drinks) can harm the dental enamel in a similar way. These processes can damage the dental enamel. It will be dissolved completely and a cavity occurs. The cavity must then be cleaned and filled. It exists a lot of dental fillings, like gold, amalgam, ceramics or polymeric materials. After filling other dangers can occur: The mechanical properties of the materials used to fill cavities can differ strongly from the ones of the dental enamel itself. In the worst case, the filling of a tooth can damage the enamel of the opposite tooth by chewing if the interaction of enamel and filling is not equivalent, so that the harder fillings can abrade the softer enamel of the healthy tooth at the opposite side. This could be avoided if the anisotropic mechanical properties of dental enamel would be known in detail, hence then another filling could be searched or fabricated as an equivalent opponent for the dental enamel with equal properties. To find such a material, one has to characterise the properties of dental enamel first in detail for the different types of teeth (incisor, canine, premolar and molar). This is here exemplary done for a human incisor tooth by texture analysis with the program MAUD from 2D synchrotron transmission images [2,3,4].

In order to get information about the transition mechanism, the temperature-induced transformation in the binary com¬pound NiS was investigated. Above 379 °C, a single crystal of millerite -NiS transforms to polycrystalline NiAs type -NiS with a sharp texture. Pole figures of both phases in the same orientation were measured using synchrotron radiation and an imaging plate detector. The Rietveld texture analysis showed that there are at least three components of the high-temperature -NiS phase. The main component shows the following orientation relations: [001]NiAs type  [001]millerite, [100]NiAs type  [210]millerite, [210]NiAs type  [100]millerite. The broad peaks of the recovered polycrystalline millerite occur at the same positions as the reflections of the original single crystal.

The exoskeleton of the crustacean Humans americans, the American lobster, is a biological multiphase composite consisting of a crystalline organic matrix (chitin), crystalline biominerals (calcite), amorphous calcium carbonate and proteins. Variations in the composition and in the crystallographic arrangement of the crystalline phases of this tissue can lead either to a rigid material serving as a protective armor layer or it can render the material highly flexible serving as a constructional element as in articular membranes at joints. Beside these properties, the exoskeleton has a rather low density in view of the high stiffness it can provide in parts. One special structural aspect which has not yet been studied in detail is the occurrence of pronounced crystallographic orientations and resulting directional anisotropic mechanical properties. So far only separate pole figures have been interpreted [I, 2]. The crystallographic textures of chitin and calcite have been measured by wide angle Bragg diffraction, calculating the Orientation Distribution Function (ODF) from pole figures by using the series expansion method according to Bunge. A general strong relationship can be established between the crystallographic and the resulting mechanical and physical properties. In biological matter this aspect seems to be of particular importance since natural constructions exploit the presence of structural anisotropy of its components in a much more efficient and elegant way than usually encountered in man-made materials.

The 'Moving Area Detector Method' with high energy synchrotron radiation allows to measure textures and microstructures of materials with high location and orientation resolution, e.g. so called Multipeak Textures. In this paper the measuring method is described shortly, as well as a description and the calculation of Multipeak Textures are given. A few examples of synthetic calculated Multipeak pole figures are shown.

The new developed “sweeping detector” techniques using high energy synchrotron radiation allow to measure textures and microstructures of materials and their change during heat treatment with high location and orientation resolution. Here we show these new methods applied to cold rolled and subsequently annealed nickel samples. The grain-resolved measurements show, impressively, many details of the recrystallization process which can otherwise not be seen. The results of these measurements can be the base for omprehensive recrystallization theories.

The newly developed “sweeping detector” technique with high energy synchrotron radiation allows to measure textures and microstructures of materials with high location and orientation resolution. This method was applied to hot rolled aluminium manganese alloys and to rolled nickel samples in different recrystallization stages. The grain-resolved measurements show, impressively, many details of the recrystallization process which can otherwise not be seen. That can be the base for comprehensive recrystallization theories.