ملخص البحث :

In recent years, the demand for high-durability parts are rising too much. These challenges are difficult to overcome without an innovative framework based on an accurate database. The problems of high stress generated due to the hard friction and severe crystal dislocation during the forming process need to be solved. High frictional forces between the contact surfaces while forming lead to high sticking between the parts. In this work, forming process of the large sheet metal has been explored based on some parameters like material properties, stress generation, and their effects on the product quality. For this purpose, square sheet metal of 721*721*5 mm is considered, and the product formation through many forming steps was carried out. This work includes adopting some design steps, modeling, and analysis to control some parameters and minimize the generation stresses. The finite element software (ABAQUS/CAE) has been adopted for analyzing this process. In this simulation, the forming process evolution in different steps has been analyzed, and the influence of the effective parameters was performed. As a result, it’s found that the generation stresses are highly concentrated near the fillet zones and proportional to the pressure, and depend on the nature of contact and friction. Simulation results also revealed that the uniform pressure during forming will leads to minimizing the friction and stress generation (5 %) and this will improve the product quality. Also, it’s possible to identify and facilitate many difficulties and evaluate the possibilities before further investing in tooling. It’s concluded that any accurate process like this must depend on some sequence steps like design, modeling, and simulation. Moreover, folding the large surface area needs accurate and adjustable types of equipment.

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Abstract. The present study is to evaluate the performance of steel reinforcement under NaCl concentration chloride exposure. The loss of weight, yield stress and ultimate stress were tested to evaluate the performance of steel reinforcement before and after exposure. The exposure was also repeated under a variable temperature of (50, 60 and 70 C0). The steel was treated to improve its properties by using hardening in the oxy-acetylene torch, epoxy coating and aluminium spread coating. Results showed that the reduction in reinforcement properties was reduced significantly by using the hardening method and the maximum reduction in the performance of steel reinforcement was in the higher temperature chloride exposure. The increasing of concentration (0.1, 0.2, 0.3 and 0.4 NaCl %) was due to high corrosion in steel wire. The results showed that the treatment of reinforcement was significantly improved.

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Research papers deals with using the strain gauge technique with equipment of dynamic strain measuring to get of maximum practical readings for "Shaping Tool Strain" which is known there physical and mechanical properties from beginning of cutting process to cutting stroke end .The" Merchant cycle" is using to analysis of cutting forces and measuring of label piece's dimensions that is getting at shear plane by changing cutting depth (2, 3 ,5 mm). The theoretical dynamic strain is determine by knowing mechanical properties of cutting material. The standard deviation (0.00016) and correction factor (0.3) that is referring to the ability of the technique can be using to improve cutting process and increase service life of tool cutting 30% approximately .The process is repeated with using one of lubricant liquid to determine dynamic strain values during lubrication and comparing with the previous one can be predict lubrication coefficient during cutting process that average value is (0.93). Key word: dynamic shear strain , shaping tool, strain gauge technique