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Most polycrystalline metals contain crystals which are not randomly oriented in space, but rather, their axes are approximately aligned with the macroscopic shape of the sample. The non-random distribution arises because of oriented processing, heat-treatment or phase transformation. The sample is then said to be crystallographically textured and exhibits macroscopically anisotropic properties, which reflect the orientation distribution. Such anisotropy can be advantageous. In ferritic iron, the magnetic flux density rises most easily along ͗100͘ directions, in contrast to ͗111͘ directions which are said to be magnetically hard. Steels which are used for electrical applications involving rapid changes in magnetic field therefore perform better in terms of energy loss, permeability as well as magnetic flux density when the crystals are aligned with ͗100͘ directions parallel to the sheet normal. The {100} planes which contain two perpendicular ͗001͘ directions and no ͗111͘ direction are naturally the planes of easy magnetisation, so a texture in which these planes are aligned to the sheet surface with the cube edges parallel to the sample axes is known as the cube texture, {100}͗001͘. A cube-on-face texture on the other hand corresponds to the {100}͗0vw͘ orientation.Due to the magnetic anisotropy, the texture control is a fundamental tool to improve magnetic properties of electrical steels and can have a very large impact on energy consumption. Electrical steels are soft magnetic iron-silicon alloys with varying silicon contents, which are used for transformers, motors, generators, alternators, ballasts and a variety of other electromagnetic applications. Since more than half of the electricity generated is used to drive electrical motors, efficiency of motors affects energy consumption significantly and thereby green house gas emissions. Typical efficiency of motors ranges from 83 to 92%, and their operating efficiency is far below, 62%.1,2) The only way to improve motor efficiency is to reduce motor losses. Loss components in an induction motor consist of the core loss in iron cores, the copper loss in rotors and stators, the stray load loss, and the friction and windage loss. 1) Among them, the copper loss and the core loss, which cover at least 75% of the overall losses, can be reduced significantly by improving magnetic flux density along with reducing iron loss through the texture control of core materials.Although the ideal texture for rotating machines is known to be the cube-on-face, there is no efficient method for its manufacture. In Fe and Fe-base bcc alloys, the cubeon-face texture does not evolve by the ordinary cold rolling and recrystallization processes. Although a strong a fiber develops during the cold rolling process, which includes the {100}͗011͘ component, it disappears almost completely after the indispensable recrystallization for good magnetic properties. The resulting recrystallization texture is a strong g fiber, instead.3) Since late 1950's, various process routes have been proposed to ...

Al 7075 alloys since the oxalic ions enhance separation between the pitting and corrosion potentials, whereas the nitrate ions appreciably increase the corrosion potential. Thus the combination of the two ions results not only in separation of the two potentials, but also to an appreciable positive shift of the pitting potential. The immersion test experiments showed a preferential dissolution of the Zn contained in the alloy in the presence of nitrate ions. ABSTRACTThe objective of this work is to provide a better understanding of the role of microstructure in intergranular stress corrosion cracking (SCC) of controlled-purity, Inconel 600type alloys in high temperature, high purity water. High purity heats Ni-16Cr-9Fe alloys with controlled additions of carbon, phosphorus, and boron were heat treated to produce chromium depletion, grain boundary impurity segregation, and inter-and intragranular precipitation of chromium carbides. Constant extension rate tensile (CERT) tests were conducted at 3600 C in deaerated (<10 ppb 02) high purity water containing a hydrogen overpressure, and in 360 to 400'C Ar atmosphere at an initial strain rate of 3 x 10 -' sew'. Rf:sults showed that (1) the high purity Ni-Cr-Fe alloy exhibited inherent lG cracking susceptibility in water and Ar, (2) prior cold work introduced by compression significantly increased IG cracking susceptibility, (3) carbon in solution enhanced IG cracking resistance, (4) phosphorus and boron segregation retarded IG cracking, and (5) chromium depletion did not affect IG cracking. The results also suggest that creep plays a role in IG cracking in 360C water and in Ar at 360 and 400' C.°

The texture can be evolved through the γ to α transformation by cooling in Fe-Si alloy systems. Oxygen in the annealing atmosphere hampers the evolution of the texture. The texture evolution is associated with the fact that the {100} faces are elastically compliant so that the texture can develop in a manner consistent with minimization of strain energy. By alloying Mn to Fe-Si alloys, the texture evolves in relatively high oxygen containing annealing atmosphere. The role of Mn in the texture evolution appears to be preventing formation of surface oxides, which modify the elastic modulus of metal surface, thereby suppress the development of the correct texture.