Pedro Américo Almeida Magalhães Júnior

Stress-Strain Compression of AA6082-T6 Aluminum Alloy at Room Temperature

Short cylindrical specimens made of AA6082-T6 aluminum alloy were studied experimentally (compression tests), analytically (normalized Cockcroft-Latham criteria—nCL), and numerically (finite element analysis—FEA). The mechanical properties were determined with the stress-strain curves by the Hollomon equation. The elastic modulus obtained experimentally differs from the real value, as expected, and it is also explained. Finite element (FE) analysis was carried out with satisfactory correlation to the experimental results, as it differs about 1,5% from the damage analysis by the nCL concerning the experimental data obtained by compression tests.

Simulation Mechanism with 2 Degrees of Freedom

This article discusses the historical analysis of the development of simulators applied to aviation. From the development with the application of the first necessity, at the beginning of the 20th century, to the nowadays technology. Today the technology is used in several fields, justifying the increasing business investment destined to the sector, such as training, recycling, development and entertainment. Its advantage, compared to the real model, is the lower cost and greater security. Some simulator mechanisms were studied in order to select one that meets practical USAge demands, and, in the end, a mechanism design is presented, aiming at the future construction and study of the different systems of a simulator in practice.

Adhesive and abrasive wear resistance evaluation of a ABNT 52100 steel from a Stretch Bending Roll coated with WC-Co and NICCr applied by the HVOF Process

The tungsten carbide coatings in the cobalt matrix (WC-Co) and nickel-chromium carbide (NiCCr) are widely used to give greater resistance to abrasive wear to carbon steel. In this work, the possibility of applying these two coatings in the ABNT 52100 steel of a stretch bending roll, with the addition or not of an intermediate NiAl layer, using the thermal spray process HVOF (High Velocity Oxygen fuel), since this process has a small thermal input and allows the possibility of applying a great variety of coatings, including non-metallic ones. It was proposed to evaluate the performance of the samples in situations of high abrasive wear, also evaluating the role of the intermediate layer to improve adhesion of the coating to the substrate. For the evaluation of the resistance to abrasive wear and adhesive, the pin-on-disc tests (ASTM G99-17) and tensile tests (ASTM E8E8M-16a), respectively, were used. The surfaces of the samples were also evaluated by optical microscopy and electronic scanning. In addition, the hardness of each sample was also evaluated. With the tests, it was concluded that the samples with higher hardness and the presence of intermediate layerpresented faults in the interface of thesubstrate with coating, and the resistance to abrasive wear did not deviate much from the values in the literature.

Analysis of Elastic Recovery in The Process of Bending Sheets of Duplex Steel SAF 2205 via Experimental Method and Numerical Simulation

The mechanical conformation is widely used in metal materials manufacture, being the bending process one of the most applied in the metal-mechanical industry. The material behavior analysis is important in this kind of process, since fabrication problems can compromise the final performance of bent components. During the bending process of metal sheets, the sheet undergoes a geometric variation after the withdrawal of the load. This effect, as known as elastic recovery, can be harmful when it is needed to fit two components with low tolerances. The comparative between elastic recovery problem analyses in folded sheets by numerical simulation and the experimental method seeks to anticipate possible inconveniences and additional costs during the try out tests. The numerical results are compared with the experimental laboratory tests. The contact and the interaction between the tool components and the sample boundary conditions are evaluated. Thereby, we consider the aspects necessary for modeling the elastic recovery in agreement with the experimental test, obtaining a very close result between the two methods.

Experimental Determination of the Convective Coefficient of Heat Transfer Using the Global Capacitance Method

The heat transfer coefficient (h) is an extremely important variable in the evaluation of convective heat transfer, however, its determination is a great challenge due to the various factors that influence it: fluid viscosity, fluid density, specific heat of the fluid, thermal conductivity of the fluid, coefficient of volumetric expansion, fluid velocity. The objective of this work is the experimental determination of the convective heat transfer coefficient by means of the global capacitance method. Three test bodies, two cylindrical bodies and one spherical body were used. These specimens were individually heated in a stove, and heating was monitored by means of a thermocouple and a data logger. The results showed a good concordance between the values of h obtained experimentally and the literature.

Introduction to the Method of Finite Elements by a balance Sheet Problem: A Simplification for an Initial understanding of the Method

The Finite Element method is one of the most widely used methods by Engineers in the various areas of activity, especially Mechanical Engineering, to design or solve problems. However, the understanding of the method is not always easy to perform, since in the literature, when explaining the method, the examples are generic or presented quickly. Thus, this paper presents the solution of a problem involving a rocking beam (set), which is solved analytically and later by the finite element method. The comparison of the solutions found is established as reflection analysis. Elasticity theory, Ordinary Differential Equations and Finite Element Method are used to approximate the reader of the Finite Element Method, in a concise and objective, easy-to-understand reading performed with a reduced explanation. Comparing the method by means of a problem.

Evaluation of the Stiffness Effect of Pipe Supports in Relation to Static and Dynamic Loads in a Flexibility Analysis

Piping flexibility analysis is done to ensure structural integrity in all operating conditions that may occur over the life of a system, whether static or dynamic. In industrial designs generally the rigidity of the support is neglected in the analysis of flexibility. The work presents an evaluation of the loads transmitted the structures in function of the rigidity of the pipe support. The evaluation was done through computer simulation using finite element techniques. The computational simulation made possible the evaluation of the forces transmitted to the support structures of an existing project of an orifice station, when considering the rigidity of the support. The work also shows that it is possible to refine projects when taken into consideration the influence of the rigidity of the supports, making a more adequate sizing the structure, portraying more faithfully the behavior of the system. The work also evaluates the influence, advantages and disadvantages in the use of stiffness in the supports with regard to the load transmitted to the support structures (support, base and tube).

New numerical method for the photoelastic technique

The objective of this research is to find new equations for a novel phase-shifting method in digital photoelasticity. Some innovations are proposed. In terms of phase-shifting, only the analyzer is rotated, and the other equations are deduced by applying a new numerical technique instead of the usual algebraic techniques. This approach can be used to calculate a larger sequence of images. Each image represents a measurement of the stresses present in the object. Every photographic image has errors and random noise, but the uncertainties due to these effects can be reduced with a larger number of observations. Keywords: photoelasticity, metrology, stress analysis, optical measurement