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Metal amorphous nanocomposites (MANCs) offer lower losses than silicon steels and higher saturation inductions than amorphous alloys. Their application in motors will require a detailed understanding of their mechanical properties. Co74.6Fe2.7Mn2.7Nb4Si2B14 was studied by nanoindentation and tensile testing to determine hardness, elongation, Young's modulus, ultimate tensile strength (UTS), and Poisson's ratio. Young's modulus was observed to increase with crystallization at 50 MPa, and then decrease when annealing under applied stress. Annealing at even higher stress resulted in no significant change in Young's modulus. This trend was replicated in nanohardness results. The UTS and elongation decrease with crystallization and show a large increase in standard deviation. Reduction in UTS and elongation has been attributed to embrittlement, as well as the high surface roughness of the ribbon material. Poisson's ratio remained relatively constant at 0.31–0.33 for all samples. X-ray diffraction (XRD) was performed on annealed samples, revealing fine nanocrystals. Profilometry indicates significant surface roughness, which contribute to reduction of UTS and elongation. Hardness, UTS, and elongation compare favorably to existing materials, but embrittlement of the material needs to be addressed to allow use in electric motor applications.

In the integration of oxy-fuel combustion to turbine power generation system, turbine alloys are exposed to high temperature and an atmosphere comprised of steam, CO2 and O2. While surface and internal oxidation of the alloy takes place, the microstructure in the subsurface region also changes due to oxidation. In this study, bare metal coupons of Ni-base superalloys were exposed in oxy-fuel combustion environment for up to 1000 h and the oxidation-related microstructures were examined. Phase transformation occurred in the subsurface region in Ni-based superalloy and led to twinning. The transformation product phases were analyzed through thermodynamic equilibrium calculations and various electron microscopy techniques, including scanning electron microscopy (SEM), orientation imaging microscopy (OIM) and transmission electron microscopy (TEM). The mechanism by which the phase transformation and the formation of the microstructure occurred was also discussed. The possible effects of the product phases on the performance of the alloy in service were discussed.

In the paper ‘‘Crystal structure and zinc location in the BaZnFe6O11 Y-type hexagonal ferrite’’ by Collomb et al. [1], the detailed list of atomic positions gives the fractional coordinate location of the Me5 atom at the 18h symmetry site as x: 0.50317, y: –0.50317, and z: 0.19073 in a hexagonal cell. We believe this to be a typographical error, and that the fractional coordinate for the z-position should be approximately z: 0.109. The Y-type hexagonal ferrite has the space group symmetry R-3m. When this symmetry is applied to the positions given in the paper, using CrystalMaker software, the center to center distance between the Me5 atoms and the O5 atoms is only 0.27 A, an unrealistic number. In the paper, the closest-approach distance between Me5 and O5 atoms is listed as 2.048 A. Since the R-3m symmetry of the system is well-documented, the issue must lie with either the oxygen or metal atom fractional coordinate. Since the oxygen positions are consistent with the placement of the other oxygen layers in the unit cell, the misalignment appears to be in the Me5 position. Another paper on Y-type