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The influence of La, Ce elements and thermal-mechanical treatment on microstructure and mechanical properties of Al-Zn-Mg-Cu alloy are presented in this study. According to the results, when the alloy was added to the La, Ce elements, after casting, the grain size of samples was around 40-50µm compared to that of without about 65µm; and then these impurity samples attained 30µm after homogeneous mixture the grain sizes. After the cold deformation process, the distance between plates is 10µm. This homogenization process contributes to increasing the ductility of the studied alloy. In addition, the EDS lines study shows that after the combination of the deformation and heat treatment, the uniformation of elements mainly focuses on the boundary and in the grain. After recrystallization annealing, the grain size is around 10 µm with the modification sample. Further, as a result of ability deformation from the tensile test, these results demonstrate that the tensile test obtained 140 % when adding La, Ce contents into the alloy combined with thermal-mechanical treatment. The combined use of La; Ce and thermal-mechanical treatment have increased the ductility of Al-Zn-Mg-Cu alloy. The combination of modification and thermal-mechanical treatment has created a small grain size for the studied alloy.

Influence of rare-earth (La, Ce) and thermo-mechanical treatment on microstructure and mechanical properties of Al-Zn-Mg-Cu alloy are presented in this article. After casting, the alloy which was modified by La, Ce, the grain size of samples obtained around 40–50 µm compared to that of without about 65 µm; and after homogeneous, the grain sizes is about 30 µm. After the cold deformation process, the distance between plates is 10 µm. By EDS after casting, the samples have tended to more La, Ce elements at the grain boundary, after homogeneous, the uniformation distribution of rare-earths was presented by mapping of EDS’s results. In addition, after rolling and heat treatment, the elements were found on the grain boundary and matrix. After recrystallization annealing, the grain size is around 10 µm with the modification sample. The grain size was reduced by two processes of modification as well as thermal-mechanical treatment is a condition for increasing the ductility of the studied alloy. Further, as a result of ability deformation from the tensile test, these results demonstrate that the tensile test obtained 140 % when adding La, Ce contents into the alloy combine with thermal-mechanical treatment. The combined used of La, Ce and thermal-mechanical treatment have increased the ductility of Al-Zn-Mg-Cu alloy

High strength elastic alloy has an important role in the manufacture of electrical equipment and machine building. Along with the development of information and telecommunications technology, the application of this alloy in electrical and electronic equipment is very increasingly. Even on boards or connectors of common electrical equipment such as computers, cell phones, these connectors are usually made of high strength elastic copper alloy. The design required features are small, precision built, with high mechanical strength and elasticity, heat resistance, abrasion and corrosion resistance in the operating environment to ensure its/the power and signal stability for a long time. The design trend is reduced in size but still assure the equipment quality is growing significantly and the corporation to manufacture equipment is researched thoroughly. Accordingly, this article presents the research results about the alloy copper with 9%Ni and 6%Sn which has the high elastic strength and elasticity properties of elastomers after heat treatment. The properties of the microstructure, hardness, conductivity, dry friction coefficient, the corrosion resistance of the alloy from which to determine the parameters for the materials selection procedure and the design of the manufacturing of magnetic contact of this alloy. The results of the study show that after heat treatment and deformation, the Cu-9Ni-6Sn has a strength of alloy up to 1200MPa, the elastic limit is 1100MPa and the conductivity is 8.4%IACS, respectively. The values ​​of this characteristic are consistent with the working conditions of the electrical contact. With the deformation process combined with the heat treatment process, the results of our research group created a single-phase homogeneous microstructure that is chemically stable with the spinodal decomposition in appropriate to the treatment of aging process. By modern methods, this paper demonstrates the durability of the alloy due to the spinodal decomposition during aging treatment at 350°C. This structure of spinodal decomposition is about 20-40nm in size, dispersed throughout the entire cross-section of the sample.

Spilled oil has been considering as extremely serious disaster in the maritime field and oil exploration, and its effects lasted for decades, even hundreds of years. Oil spill treatment and recover...

This paper’s aim is to describe the results of the phase transformation of BCuAl9Fe4 alloy after casting, quenching and aging. After casting, the microstructure of this alloy consists of [Formula: see text] phase with grain size about 100 [Formula: see text]m, mixture [Formula: see text] and the inter-metallic phase Fe3Al. However, the proportion of the [Formula: see text] phase in the casting alloy is coarse. The alloy was heated at [Formula: see text]C for 2 h then quickly cooling in water. After quenching, the microstructure of alloy shows that the grain size reduced to about 40 [Formula: see text]m. After quenching, the alloy was aged at [Formula: see text]C for 2 h, the martensite phase of this alloy decomposed into order phase ([Formula: see text] with fine grain size, dispersed in the matrix. The intermetallic phase was fine and evenly dispersed in the matrix. By TEM analysis, after heat treatment, the structure of martensite and the inter-metallic phase in this alloy which had small grain size were formed.

This paper investigates a high electrical conductivity and high strength of alloys based on Cu-Ni-Si system It proclaimed the results of the effect of tin (Sn) component on the mechanical properties and microstructure of Cu-Ni-Sn alloy. The conditions for processing the Cu-Ni-Si alloy were presented, the analysis of microstructure and mechanical properties after heat treatment was examined by X-ray, SEM, EDS and specialized machines. The results showed that with 3% mass of Sn added into the Cu-Ni-Sn alloy along with heat treatment and deformation, the hardness value reached the range of 221-240HV, the tensile strength and elastic limit reached around 1060MPa and 903MPa respectively. However, after heat treatment and deformation for the Cu-Ni-Sn alloy based on 6% mass of Sn, the hardness value reached the range of 221-318HV, the tensile strength and elastic limit were respectively 222MPa and 263MPa higher than those of the Cu-Ni-Sn alloy with 3% mass of Sn. The result from X-ray analysis showed the deflection of peaks. Nonetheless, the new phases were not observed in SEM and EDS, contrariwise, generated modular structure was considered as the proof of the Spinodal cluster. This fact might be explained by two mechanisms: deformation mechanism and Spinodal decomposition.

The thermal spray has been commonly used in several applications to replace the plating technology due to high adhesion, low cost, and environmental pollution. The thermal coating is usually used to rehibilitate the small disrepair of the crankshaft but the dimension and mechanical properties of such parts are still maintaned. Commonly, the microstructure and mechanical properties are greatly affected by depth of thermal coating, and thermal coating needs to be conducted the heat treatment to homogenize the microstructure between metals of coating and base metals as well as to improve the adhesion, hardness, and wear intensity. In this work, the effects of heat treatment on the microstructure and mechanical properties of the coating layer based on 80Ni-20Cr onto the surface of CT38 steel were conducted. SEM images and EDS analysis were used to determine the distribution of elements before and after heat treatment. In addition, mechanical properties such as Vicker hardness (HV), wear intensity, and adhesion were practically measured. As a result, after heat treatment by annealing under 1100oC during 8h, HV and adhesion were significantly higher than the case of non-heat treatment; meanwhile, wear intensity was found with 3 times lower compared to the unheated sample. The strong bi-lateral diffusion between Cr from coating layer and C from CT38 steel component to form carbide along with a formation of bond Ni-Fe was thought to be the main cause resulting in the improvement of mechanical properties and was demonstrated in this study.