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Analyzing the diffusion kinetics behavior that leads to precipitates formation can assist in understanding the properties of Zr alloy materials. In this study, coarsening growth kinetics of precipitates in N36 zirconium alloy with Nb dominant are experimentally calculated during the isothermal and isochronal aging process (580 °C–700 °C, 0.5–30 h respectively). Microstructure observation and the second phase particles (SPPs) have been investigated and numerically extracted through several processes, including the use of an optical microscope (OM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), in addition to image software tools. Conclusions confirm that as the temperature or aging period increases, the SPPs begin to lose fine and linear distribution properties ranging from α-plate grain boundary to the random distributions. Moreover, the small particles dissolve, whereas the

In this study, the initial temperature of the (α) to (α + β) phase transformation of β-quenched N36 zirconium alloy was determined using differential scanning calorimetry (DSC) and metallographic techniques. Diagnosis and analysis of the difference between the two techniques were also conducted. It was found that the phase transition temperature, obtained by metallographic techniques, lies in a temperature range of 710–715 °C. This value is lower than that recorded by DSC analysis. A peak separation successfully explained the dissolution of the second phase particles (SPP)s and α→β phase transformation using the DSC analysis. Compared with previous studies, the results of this study showed that β-quenched starting material is responsible for the delay of β-Zr formation during the heat treatment of the N36 zirconium alloy.

In-situ tension test in a transmission electron microscope (TEM) was used to study the fracture process of aluminium, as well as the real-time crack formation process and atomic-scale results of crack tip propagation were captured. The experimental results show that multiple Frank-Read dislocation sources are formed in the crystal thinning area at the front of the crack, and the nanocrack nucleates on the dislocation loops emitted by the dislocation source. The perfect dislocations that were continuously emitted from the crack tip slip and decompose in the crystal, resulting in the relative rotation of the crystal to form a twin boundary. After the perfect dislocation decomposition, a part of the residual dislocation formed a dislocation wall at the twin boundary to form a subgrain boundary, and the other part formed a stacking fault, and then the residual dislocation dragged the stacking fault to slip at the twin boundary.

As a new type of grain refiner, rare earth element Sc has a strong grain refining effect on the microstructure of cast aluminum alloys. During the solidification of Sc-containing aluminum alloys, Al3Sc particles are formed in the molten metal and act as heterogeneous nucleation cores of Al in the nucleation process, which significantly increases the nucleation rate and refines the grains. In this paper, a focused ion beam (FIB) microscope was used to extract Al3Sc particles from an Al-Sc alloy, and the internal structure of the particles was systematically observed. At the same time, a scanning electron microscope (SEM) and high-resolution transmission electron microscope (HRTEM) were used to study the morphological characteristics of particles and the crystallographic orientation relationships (ORs) at the interface. The study found that under the influence of strong anisotropy, the growth rate of Al3Sc crystal high …

Abstract: Low carbon steels wide range using materials, chemical composition and physical properties controls by using heat treatment process that including heating and then cool by appropriate quenching mediums. The effects of polyethylene glycol diluted with water as quenching medium on the mechanical properties (hardness, compression) and microstructural properties of low carbon steel were investigated with the aim at improving their compatibility with polymer quenching. The tested samples were prepared and subjected to heat treatment process used electrical resistance furnace soaked for 1 hour and then quenched in polyethylene (PE) diluted with water in controlled percentages of PE% (25%, 35%,45%). Used digital microhardness and universal test machine resulted an enhancement in their mechanical properties, they though (PE) gives good cool rates. The dominant of martensitic phase in microstructures resulting in their enhancement of low carbon steel properties. The hardness improvement about 83.5% as illustrated with this paper, also the compressive strength improved about 23.3% with this work. Also, an enhancement of surface cracks was observed with increasing (PE) percentage. It is assumed that polyethylene solution will help to develop high performance of low carbon steel properties for industrial fields applications

Incremental sheet metal forming is adaptable rapid manufacturing in sheet forming process that lead to cost and time effective and good quality products, more flexible and less set up cost to any complexity parts, so that it is highly versatile nowadays. Therefore, incremental sheet metal forming technology solving many problems found in conventional sheet forming. More than researchers continue in studying improvement (ISMF) process. In this work, simple and complex shapes manufacture by Single Point Incremental Forming process (SPIF) without using a dedicated die depending on helical tool path was generated by Unigraphics- NX10 (UGS-NX10) programing system. The aim of the presented work is to investigate the feasibility of the incremental forming process for different geometry shapes by using computer numerical control (CNC) depending on zero spindle speed using 1050 aluminum sheet material. The results from this work gives good indication about the complexity of using different shapes in (ISMF). Therefore, improvement of this process by using different shapes as a design tool for incremental sheet forming very important things.