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High-temperature processes induce creep and corrosion, primarily resulting in failure of thin-walled pressure vessels. Investigating alloy creep behavior in these vessels is crucial due to its often undetected nature, leading to sudden and costly failures, posing irreversible risks to health and the environment. This study investigates the creep behavior of carbon steel A516-Gr70 at different loads at a constant temperature of 600 °C. The specimens were subjected to high-temperature creep tests until failure at the specified temperature and at different loads of 100, 150, and 250 kg. The results indicated a nearly linear correlation between the creep rate in the stable region and the applied load. Additionally, it was observed that utilizing the hardness versus time-to-failure diagram enables the prediction of the remaining creep life of the components. [ABSTRACT FROM AUTHOR]

This study investigated the effect of ferrite band formation for preventing the diffusion of molten copper (Cu) into steel grain boundaries. To this end, the gas tungsten arc welding method was exploited for cladding ERCuAl-A2 and ERCuSi-A filler metals on plain carbon steel. Then, microstructure, cracks, and ferrite bands were characterized and the conditions for the formation of 4.20 wt.% Si in the ferrite band were evaluated using the design of experiments methodology. The results indicated that when cladding with 7.60 wt.% Si takes place with minimum heat input (0.9 kJ/mm), the penetration of the molten Cu will not occur in the grain boundaries of the heat-affected zone in the presence of the %overlap. [ABSTRACT FROM AUTHOR]

Values of some haematological indices were assessed in 30 Barbus grypus (mean length, 22.88 ± 4.16 cm; mean weight, 101.01 ± 58.50 g). The fishes were randomly selected from ponds of Dashte Azadegan Aquaculture Centre. The blood samples were collected from the caudal vein after adaptation to laboratory conditions. The values of the haematological parameter were measured using standardized and approved methods. The following values (mean±SD) were recorded. Packed cell volume (PCV), 46 ± 5.71%; haemoglobin (Hb), 9.5 ± 4.58 g/dL; white blood cell, 3,196.6 ± 716.54 in each mm; red blood cell, 1,378,667 ± 195,408.2 in mm, mean corpuscular haemoglobin concentration, 34.68 ± 20.23%; mean corpuscular haemoglobin 12.53 ± 70.02 (pg); mean corpuscular volume, 7.58 ± 34.1 (fl); neutrophils, 25.40 ± 6.04%; lymphocytes, 72.2 ± 4.58%; monocytes 1.13 ± 0.97% and eosinophil 0.6 ± 0.67%. A significant ( p < 0.05) interaction was found between total length, weight and PCV as PCV value increases with increasing weight and length. Data obtained from this study will serve as baseline haematological parameters for use in monitoring of health and productivity of B. grypus regarding the increasing interest in this fish for aquaculture purposes. [ABSTRACT FROM AUTHOR]

The development of Friction Stir Welding (FSW) has provided an alternative approach for producing high-quality welds, in a fast and reliable manner. This study focuses on the mechanical properties of the dissimilar friction stir welding of AA6061-T6 and AA7075-T6 aluminum alloys. The FSW process parameters such as tool rotational speed, tool traverse speed, tilt angle, and tool offset influence the mechanical properties of the friction stir welded joints significantly. A mathematical regression model is developed to determine the empirical relationship between the FSW process parameters and mechanical properties, and the results are validated. In order to obtain the optimal values of process parameters that simultaneously optimize the ultimate tensile strength, elongation, and minimum hardness in the heat affected zone (HAZ), a metaheuristic, multi objective algorithm based on biogeography based optimization is proposed. The Pareto optimal frontiers for triple and dual objective functions are obtained and the best optimal solution is selected through using two different decision making techniques, technique for order of preference by similarity to ideal solution (TOPSIS) and Shannon’s entropy. [ABSTRACT FROM AUTHOR]

The properties of aluminum alloy AA6061-T6 after aging at 220°C for 0.5 - 8 h are studied by the methods of light and scanning electron microscopy and fractography. The mechanical characteristics of the alloy are determined by tensile tests. [ABSTRACT FROM AUTHOR]