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Doping is an effective way to optimize the performance of thermoelectric materials. In order to investigate the effect of Bi doping on microstructures and thermoelectric properties of Ge0.90Pb0.10Te, a series of Ge0.90−xPb0.10BixTe compounds were prepared by a melting-quenching-annealing process followed by spark plasma sintering. The Bi doping on Ge site acts as an electron donor, which effectively optimized the carrier concentration from 1.1 × 1021 cm−3 to 3.5 × 1020 cm−3. Besides, the lattice distortions originated from Bi doping further promoted the solubility of Pb in the GeTe matrix, which have great advantage for obtaining lower thermal conductivity compared with pristine Ge0.90Pb0.10Te sample. Low lattice thermal conductivity of about 0.77 W/mK was obtained in Ge0.86Pb0.10Bi0.04Te owing to the additional lattice defects introduced by Bi doping. Consequently, the highest ZT of 1.1 was obtained in Ge0.86Pb0.10Bi0.04Te at 600 K with an average ZT of 0.6. These results have confirmed that Bi doing is an efficient way to boost the thermoelectric performance of GeTe-based alloys.

Ferritic steels containing copper have been studied as model systems for clusters/precipitate formation in reactor pressure vessel steels. The samples were aged at 400 °C for 4000 h and subsequently cold rolled to 30% reduction at room temperature. The microstructural characteristics of the samples were analyzed using high-resolution transmission electron microscopy. Direct evidence was found that the fivefold twinning occurs via simultaneous emission of two Shockley partial dislocations from two particular α-Fe/Cu interfaces, and then the pileup tips of the twofold twin.

Al and Ti doped ZnO thin films have been prepared by direct current magnetron cosputtering and thermal oxidation. The effects of these dopants on the microstructural, morphological and electrical properties of deposited films have been studied. The SEM demonstrated that the undoped ZnO thin film consisted of globular ZnO with particle size of ∼100 nm. Scanning electron microscopy EDX analysis confirmed that the dopant content in the ZnO–Al and ZnO–Ti thin film was 2·78 and 3·75 at-% respectively. The particle in the ZnO–Ti thin film was blocky or granular with thorns and its size was several micrometers, while the particle in ZnO–Al thin film was porous granular and the size was ∼2 μm. Resistance value testing and R/R calculation revealed that pure ZnO thin film had the highest gas sensitivity.

4 mol.% Y 2 O 3 stabilized ZrO 2 (YSZ) doped with various quantities of Gd 2 O 3 (G-YSZ) ceramic coatings were synthesized by electrophoretic deposition method, and followed by vacuum sintering and isothermally annealing at 1000 °C for different durations. X-ray diffraction (XRD) was used to investigate their phase composition. Scanning electron microscopy (SEM) was employed to examine their microstructure, while energy dispersive X-ray spectrometer (EDS) was used to assess composition of the composite coatings. The results indicated that YSZ coating was composed of tetragonal and monoclinic phase after vacuum sintering at 1000 °C for 2 h under vacuum ( −3 Pa). G-YSZ composite coatings were composed of tetragonal, monoclinic phase and a small amount of Gd 2 Zr 2 O 7 phase after vacuum sintering at 1000 °C for 2 h, whereas the content of monoclinic phase in G-YSZ composite coatings increased with increasing Gd 2 O 3 concentration. It was found that G-YSZ composite coatings were composed of tetragonal ZrO 2 phase, monoclinic ZrO 2 phase and cubic phase, whereas Gd 2 Zr 2 O 7 phase disappeared, after G-YSZ composite coatings were isothermally annealed at 1000 °C in air for 100 h. A detailed description of the results and their discussion was presented in the paper.

The TiN/Ni composite coatings were deposited on 7005 aluminium alloy by high speed jet electroplating and then processed with plasma transferred arc(PTA) scanning process. The microstructure, microhardness and friction coefficient of PTA scanning treated specimens were investigated. It is shown that the PTA scanning treated specimens have a rapidly solidified microstructure consisting of the uniformly distributed TiN phase and fine Al3Ni2 intermetallic phases. The composite coating has an average microhardness of approximately HV 800. The friction coefficient of PTA scanning treated specimens (oscillated at around 0.25) is considerably lower than that of TiN/Ni composite coating (oscillated at around 0.35). The corrosion behavior of the composite coating in 3.5% NaCl solution at room temperature was also determined using a potentiostat system. In comparison with the corrosion potential ϕcorr of −0.753 V for 7005 aluminium alloy, the corrosion potentials for TiN/Ti composite coating and PTA scanning treated specimen are increased by 0.148 V and 0.305 V, respectively. The PTA scanning treated specimen has the lowest corrosion current densityJcorr as well as the highest corrosion potential ϕcorr, showing an improved corrosion resistance compared with 7005 aluminium alloy.

Exchange coupling multilayer thin films, which combined giant magnetostriction and soft magnetic properties, were of growing interest for applications. The TbFe/FeAl multilayer thin films were prepared by dc magnetron sputtering onto glass substrates. The microstructure, magnetic, and magnetostrictive properties of TbFe/FeAl multilayer thin film was investigated at different annealing temperatures. The results indicated that the soft magnetic and magnetostrictive properties for TbFe/FeAl multilayer thin film compared with TbFe single layer film were obviously improved. In comparison with the intrinsic coercivity J H c of 59.2 kA/m for TbFe single layer film, the intrinsic coercivity J H c for TbFe/FeAl multilayer thin films rapidly dropped to 29.6 kA/m. After optimal annealing (350 °C×60 min), magnetic properties of H s =96 kA/m and J H c =16 kA/m were obtained, and magnetostrictive coefficient could reach to 574×10 −6 under an external magnetic field of 400 kAm −1 for the TbFe/FeAl multilayer thin film.