The description of texture by means of a small number of components (preferred orientations) is an exceptionally concise method. It may reveal relevant information about the texture modifying process
even in those cases where the texture information, contained in the experimental pole figures, is rather limited. Some examples for texture estimates and interpretation of local textures in thin layers (SiC films synthesized by carbonization of silicon with fullerenes) and bulk materials (shear bands in brass and titanium) are presented.

K. Helming

B. Rauschenbach

R. A. Schwarzer

Analysis of Crystallographic Texture in Small Sample Areas

Although the smoothing of experimental pole-density data modifies the primary data set, the effect
of such a procedure on the Orientation Distribution Function and on the interpretation of the texture
was not considered until recently. The influence of smoothing on texture reproduction will be derived
for the case, that the Orientation Distribution Function is approximated by a linear combination of
normal distributions (ideal orientation components) and smoothing is carried out with normal
distributions, too. The characteristic component parameters are well-suited to indicate changes of the
Orientation Distribution Function. The observed texture variations as a consequence of smoothing lead
to the conclusion, that moderate smoothing does not falsifythe texture. Several possibilities to control
the effect of smoothing will be discussed. Based on the visual comparison of smoothed and unsmoothed
pole-figures it is argued, that even extreme smoothing may be useful for some purposes.

D. I. Nikolayev

K. Ullemeyer

The Effect of Smoothing on ODF Reproduction

Typical experimental situations of texture measurements are demonstrated involving failure to take into
account some physical factors responsible for an inadequate texture description or imaginary texture
changes. Among these factors there are inevitable texture inhomogeneities, inhomogeneous distribution
of defects in deformed metal materials and resulting inhomogeneous lattice perfection by their heat
treatment. It is shown that a formal approach to texture analysis does not allow to reveal a number
of important regularities of structure formation.

Yu. Perlovich

Some Physical Errors of X-Ray Texture Measurements

A new algorithm of quantitative texture analysis (QTA), which is called the modified maximum entropy method (MMEM), has been proposed and applied to determination of textures in polycrystalline samples of lower crystal symmetry with overlapping diffraction peaks (Wang and Xu, 1995a). By introducing directly the maximum entropy principle into the least square procedure of pole figure inversion (Bunge, 1969), then both minimizing the differences between experimental and postulated pole figure data, and maximizing entropy may be satisfied simultaneously. Thus, the maximum entropy principle is applied to the entire process of QTA in frame of the harmonic method (HM). The detailed comparisons among the three pole figure inversion methods, i.e. the traditional HM, the primary maximum entropy method (MEM) and the MMEM, are given through a model example of simulated fiber texture. It is shown that the precise and stable solution of inverse pole figure for the polycrystalline samples with smooth or sharp textures will be obtained by the MMEM even using a less number of pole figures. The minimum range of polar angle and the least number of pole figures, which are needed in the QTA for pretended tetragonal materials by the MMEM, are discussed in detail.

Y. D. Wang

J. Z. Xu

Z. D. Liang

The Modified Maximum Entropy Method (MMEM) in QTA for Lower Symmetry Polycrystalline Aggregates

A method is described that can be used for determining the retained austenite concentration in steel samples that have texture. The method is based on symmetrized harmonics expansion for the representation of the orientation distribution of the crystallites in the sample and it presumes the use of specimen spinner on the data collection.For demonstrating the application of this method integrated intensities of seven reflections from three steel samples with different degree of texture is measured using <i>CuK&#x3B1;</i> radiation and the retained austenite concentration is determined.

Matti J&#xE4;rvinen

Texture Effect in X-Ray Analysis of Retained Austenite in Steels

The present work is devoted to the extraction of pole figures from time-of-flight neutron spectra with
different methods. Two aspects are mainly considered. The first one is to give a quantitative estimate
of the errors in the extracted pole figures and to relate the errors of spectra to the errors of the pole
figures. The second aspect is to elaborate criteria to determine the minimal exposure time, which is
necessary to accumulate a spectrum with an acceptable error level.

V. Luzin

D. Nikolayev

On the Errors of the Experimental Pole Figures

The development of the crystallographic preferred orientation &#x28;texture&#x29; of polycrystalline pyrrhotite from
Sullivan mine, Canada, and Cerro de Pasco, Peru was determined by neutron texture analyses before
and after experimental deformation. The pyrrhotite ore from Sullivan has an initial texture with a distinct
c-axis maximum perpendicular to the foliation whereas the ore from Cerro de Pasco shows a weak
and moreover inhomogeneous texture within the specimen.The deformation texture and deformation behaviour of samples from Sullivan were investigated as
a function of temperature, total strain and the angle between the compression axis and the initial c-axis
maximum. The deformation textures show the influence of different activated glide modes as a
function of the compression direction and temperature. Investigations of the deformation texture and
deformation behaviour of samples from Cerro de Pasco were carried out as a function of temperature,
total strain and strain rate. The inhomogeneous texture of the starting material did not allow to draw
conclusions about the texture development as a function of strain rate and temperature. Nevertheless
the preferred orientation of the c-axes parallel to the compression axis becomes more evident with
increasing total strain.

Elke Niederschlag

Heinrich Siemes

Influence of Initial Texture, Temperature and Total Strain on the Texture Development of Polycrystalline Pyrrhotite Ores in Deformation Experiments

H. J. Bunge

In Memoriam William Hsun Hu

Natural chalcopyrite samples from Mt. Isa, Australia were axially shortened at a constant confining
pressure of 300 (400) MPa, at different temperatures from 25&#x2013;450&#xB0;C, in the strain rate range of
<mml:math id="E1" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mn>3</mml:mn><mml:mo>&#x22C5;</mml:mo><mml:msup><mml:mrow><mml:mn>10</mml:mn></mml:mrow><mml:mrow><mml:mo>&#x2212;</mml:mo><mml:mn>5</mml:mn></mml:mrow></mml:msup><mml:mo>&#x2212;</mml:mo><mml:mn>6</mml:mn><mml:mo>&#x22C5;</mml:mo><mml:msup><mml:mrow><mml:mn>10</mml:mn></mml:mrow><mml:mrow><mml:mo>&#x2212;</mml:mo><mml:mn>8</mml:mn></mml:mrow></mml:msup><mml:msup><mml:mrow><mml:mtext>sec</mml:mtext></mml:mrow><mml:mrow><mml:mo>&#x2212;</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>. Neutron diffraction texture analyses of all deformed samples were carried out and compared to the preferred orientation before the experimental deformation.The preferred orientation of the experimentally undeformed samples consists of three main orientation components, which become weaker with deformation at temperatures to 200&#xB0;C. One or two new components &#x28;A, B&#x29; develop with the c-axes perpendicular to the principal strain direction. At a deformation temperature of 250&#xB0;C and to slower strain rates at 200&#xB0;C the relics of the original components are stronger. After deformation at temperatures of 300&#xB0;C to 450&#xB0;C in general two different types of preferred orientation were detected. One type &#x28;2NF&#x29; shows two different new components &#x28;A<sup>&#x2A;</sup>, C&#x29;, the original components are completely dissolved. The other type &#x28;IN&#x29; shows the original components partially more concentrated, especially to slower strain rates, and shifting into the directions of the new components of the type 2NF.

E. M. Jansen

H.-G. Brokmeier

H. Siemes

Neutron Texture Investigations on Natural Mt. Isa Chalcopyrite Ore &#x2013; Part II: Preferred Orientation of Chalcopyrite After Different Experimental Deformation Conditions

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Texture, Stress, and Microstructure