Mg-1.6Gd binary alloy was subjected to uniaxial warm rolling at a unidirectional and cross-sectional with a reduction ratio of 95% in order to observe the relationship between its microstructural changes to the degradation behavior. The warm rolling was performed at a temperature range of its recrystallization temperature, which were 400°C and 560°C, and a feed rate of 10 mm/min. Degradation behaviors of Mg-1.6Gd binary alloy was evaluated by means of potentiodynamic polarization and hydrogen evolution test in modified Kokubo’s SBF solution at temperature of 37 ± 1ºC. The lowest corrosion rate of 0.126 mm/year derived from potentiodynamic polarization test was showed by unidirectional-rolled specimen at temperature of 560 °C. Hydrogen evolution test results showed the lowest hydrogen gas formed during 24 hours of immersion was found on unidirectional-rolled specimen at temperature of 560°C with a rate of 0.268 cc/cm2/hours. While cross rolled specimens showed a high corrosion and hydrogen evolution rate of 20 mm/year and 0.28 cc/cm2/hours.

The paper presents research of metallic glass based on a Mg72Zn24Ca4 alloy. Metallic glass was prepared using induction melting and further injection on a spinning copper wheel. The X-ray diffractometer and differential scanning calorimeter (DSC) were used to investigate the phase transformation of the amorphous ribbon. The heat released in the crystallization process, during isothermal annealing, based on the differential scanning calorimeter investigation, was determined to be 166.18 Jg-1. The effect of isothermal annealing temperature on the kinetics of the amorphous alloy crystallization process using differential scanning calorimeter was investigated. For this purpose, two isothermal annealing temperatures were selected. The incubation time decreases as the temperature of the isothermal annealing increases from 300 to 252 seconds. The same relationship is visible in the case of duration of the phase transformation, which also decreases as the temperature of the isothermal annealing increases from 360 to 228 seconds. The obtained results show a significant influence of isothermal annealing temperature on the degree of phase transformation.

High-power terahertz sources operating at room-temperature are promising for many applications such as explosive materials detection, non-invasive medical imaging, and high speed telecommunication. Here we report the results of a simulation study, which shows the significantly improved performance of room-temperature terahertz quantum cascade lasers (THz QCLs) based on a ZnMgO/ZnO material system employing a 2-well design scheme with variable barrier heights and a delta-doped injector well. We found that by varying and optimizing constituent layer widths and doping level of the injector well, high power performance of THz QCLs can be achieved at room temperature: optical gain and radiation frequency is varied from 108 cm⁻¹ @ 2.18 THz to 300 cm⁻¹ @ 4.96 THz. These results show that among II–VI compounds the ZnMgO/ZnO material system is optimally suited for high-performance room-temperature THz QCLs.

The magnesium alloy investment castings have greater potential for automobile and air-craft applications due to the higher strength to weight ratio of magnesium alloys and capability of the investment casting process to produce near net shape complex castings. The interfacial-mould metal reactions during investment casting of magnesium alloy inhibit successful production of quality castings. This paper presents the investigation done on the reactions at corners of AZ91 magnesium alloy cast part produced through investment casting. The stepped shape geometry of casting was selected to study the reactions at convex and concave corners of the cast part. The reacted surfaces were characterised using the SEM-EDX and XRD. The formation of oxides was observed on cast surface from characterisation. The temperature profile recorded at corners were helpful to understand the heat dissipation during the solidification of metal at corners. It was observed that the reactions occurred at the concave corner were more as compared to the convex corner of the cast part.

This paper aims to investigate the microstructural evolution and mechanical properties of hot-deformed AlMg4 alloys with Mn, Fe, and Si as the main impurities. For this purpose, solidification behavior and microstructural evolution during hot-rolling and heat-treatment processes are investigated by using theoretical calculations and experimental characterization. The crystallization and morphological transformation of intermetallic Al3Fe, Al6Mn, and Mg2Si phases are revealed and discussed in terms of the variation in chemical composition. Following a homogenization heat-treatment, the effect of heat treatment on the intermetallic compounds is also investigated after hot-rolling. It was revealed that the Mg2Si phase can be broken into small particles and spherodized more easily than the Al3Fe intermetallic phase during the hot-rolling process. For the Mn containing alloys, both yield and ultimate tensile strength of the hot-rolled alloys increased from 270 to 296 MPa while elongation decreased from 17 to 13%, which can be attributed to Mn-containing intermetallic as well as dispersoid.

This article deals with the effect of manganese that is the most applied element to eliminate the negative effect of iron in the investigated alloy AlSi7Mg0.3. In this time are several methods that are used for elimination harmful effect of iron. The most used method is elimination by applying the additive elements, so-called iron correctors. The influence of manganese on the morphology of excluded ironbased intermetallic phases was analysed at various iron contents (0.4; 0.8 and 1.2 wt. %). The effect of manganese was assessed in additions of 0.1; 0.2; 0.4 and 0.6 wt. % Mn. The morphology of iron intermetallic phases was assessed using electron microscopy (SEM) and EDX analysis. The increase of iron content in investigated alloys caused the formation of more intermetallic phases and this effect has been more significant with higher concentrations of manganese. The measurements carried out also showed that alloys with the same Mn/Fe ratio can manifest different structures and characteristics of excluded iron-based intermetallic phases, which might, at the same time, be related to different resulting mechanical properties.