Orientador: Sérgio Tonini Button / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-27T18:58:44Z (GMT). No. of bitstreams: 1 Batalha_MarioHenriqueFernandes_M.pdf: 5393156 bytes, checksum: a53f9730323b17df3ef4631f7f7de1e7 (MD5) Previous issue date: 2015 / Resumo: Este estudo teve como finalidade avaliar a estampabilidade de chapas de aço de ultra-alta resistência mecânica (da sigla inglesa UHSS), neste caso o aço DIN 27MnCrB5-2 (nº 1.7182), para a estampagem a quente com estiramento controlado. Esse processo é conhecido por associar a alta produtividade da estampagem com o tratamento térmico de têmpera durante a conformação, o que se torna vantajoso no caso de aços UHSS, já que simultaneamente, reduz os esforços durante a conformação, praticamente elimina o efeito de retorno elástico e permite gerar produtos com limite de resistência superior a 1.500 MPa. O objetivo principal de associar a redução de espessura à estampagem a quente é de gerar uma peça que atenda aos esforços aplicados e que não apresente variações bruscas de microestrutura devidas à variação local na têmpera ou pela união de chapas que seria uma alternativa para a obtenção de seções com espessuras diferentes. Além disso, também tem-se por objetivos elevar a complexidade geométrica, diminuir o peso do componente estrutural e reduzir o custo de produção. Nesse caso, buscou-se avaliar a capacidade do material de confeccionar peças com redução de espessura variável durante a conformação a quente, por meio da análise dos limites de conformabilidade, obtidos pelo ensaio Nakazima em um modelo real e outro virtual, no caso, utilizando o software Forge 2008 ® que é baseado no método de elementos finitos. Além disso, foi confeccionado um componente com variação de espessura em sua parede, a fim de exemplificar em um modelo real a aplicação das informações obtidas no ensaio Nakazima. Ao final da análise, foi possível determinar uma faixa de deformação verdadeira segura de trabalho, válida para os diferentes estados de tensão e deformação, e verificou-se uma coerência na previsão do modelo virtual previamente calibrado com os resultados experimentais / Abstract: This study aimed to evaluate the formability of ultra-high strength steel (UHSS), in this case the DIN 27MnCrB5-2 (No. 1.7182), for hot stamping with controlled stretching. The process is known by its high productivity in stamping with simultaneous heat treatment of quenching, which is advantageous in the case of UHSS steel, since it simultaneously reduces the loads during forming, practically eliminates the "springback" effect and generates products with ultimate tensile strength exceeding 1.500 MPa. The main purpose of associating the reduction of thickness with hot stamping, is to generate a continuous structure that support the loading, or in other words, without abrupt changes in microstructure due to local variation in quenching conditions or welding of blanks which is another alternative to obtain parts with different thickness along the product. Moreover, it allows high geometric complexity, reduce component weight and reduce the cost of production. In this context, it was evaluated the capacity of the material to produce parts with variable thickness reduction during forming, by analyzing the limits of formability obtained by Nakazima test in a real and virtual model with the software Forge 2008 ® which is based in the Finite Element Method. Furthermore, it was manufactured a component with varying thickness in its wall, in order to exemplify the application of the data obtained in the Nakazima tests. After the analysis, it was determined a range of safe deformation, valid for the different states of stress and strain, also it was noticed a consistency in predicting hot formability between the virtual calibrated model and experimental results / Mestrado / Materiais e Processos de Fabricação / Mestre em Engenharia Mecânica

The master’s thesis deals with proposal of technological process for production of computer case in EMKO Case a.s. Computer case is manufactured from a DX51D + Z275 steel sheet with thickness 1 mm. For manufacturing were chosen technology punching and press-brake bending as the best technologies. Master’s thesis contains literary studies of these chosen technologies. Based on literary studies were made technological calculations, proposal of technological process and choice of machines. For punching was chosen machine TRUMPF TruPunch 2000, for press-brake bending hydraulic machine TRUMPF TrumaBend 50V. For chosen solution is made technical and economical evaluation.

The thesis focuses on the production concept of component Cage ECR 10 12, which is used as assembly element together with a nut during the bus production. Sheet metal part is made from 11 321 steel 1,5 mm thick in production 10 000 parts per year. Technology of production in progressive tool was selected based on literature study. Progressive tool combines technology of shearing and bending. Tool was designed after the technological calculations. Forming machine was selected after the stamping force calculation. Eccentric press LEN 63 C with 630 kN forming force was selected for production.

This master’s thesis is focused on the design of the technology to produce a part of the TV bracket. The part is made of steel sheet with a thickness of 2.5 mm. The structural steel S235JR was chosen as the most suitable material with following powder coating. From the possible variants, the production by progressive forming tool was chosen with respect to production requirements and a series size of 30 000 pieces by year. The part will be made in seven steps in designed tool and the total required force is 1013 kN. The production will take place on a mechanical press PCK12 from Bliss-Bret with a maximum force of 1250 kN. The final price of the part is 39.4 Kč.

This master´s thesis focuses on the concept of manufacturing of carbon brush holder, made of steel S235JRG (ČSN 11 343), with thickness of 1,5 mm. In order to reduce costs, it was decided to manufacture the holder with progresive stamping tool, which combines cutting, bending and edging operations in order to achieve specific part shape. Based on relevant calculations the mechanical press LEN 63 C was chosen. The production series was set at 50 000 pieces.

Project elaborate in terms of engineering studies branch 2303T002 submits proposal technology of production single parts from deep drawing press steel metal plate 11 305.21. On the basis literary study problems blanking, deep drawing and calculations was designed drawing in instrument with holder, to extrusion components serves lower ejector. Combination tool is set on hydraulic press CTH 250 with nominal tensile by force 250 kN. Drawable tools (drawing punch, drawing die) and shear pin tools (blanking punch, blanking die) are made from instrumental steels 19 436.3, heat treated condition to drawing documentation.

The project drawn up within engineering studies, field N2307-00, presents a design for processing a single part – the part is made of sheet steel number S235JRG1 by shearing and bending. On the basis of literary study was design compound tool which is working in three steps. The tool is fixed in eccentric press LEN 40 C (producer TOMA Industries, s.r.o.) with nominal force 400 kN. Blanking punch and blanking die are made from tool steel 19 436 according the drawing documentation.

The project, which have been created within the framework study of engineering branch N2301-2, submit technology project of presswork – car reinforcement from material H 220 P and concept of multi-tool set design for pressing operations 1, 2 and 3. Technology process was designed in six operations, based on literary study of blanking and drawing technology. Multi-tool set is design in according with transfer press Müller Weingarten 1250T-1, which was chosen on the basis of advantageousness calculation. Project includes technical and economical evaluation of elaborated technology whit two other variants of production.

The project elaborated in frame of engineering studies branch 2303T002. The project is submitting design of technology production of the part from the deep drawing sheet iron 11 320.30. Pursuant to of the literary pursuit a problem of the shearing, bending and calculation was designed manufacturing in transfer combined die, which is set on the eccentric press LEXN 100 C (producer TOMA INDUSTRIES s.r.o. Trnava), with nominal force 1000 kN. Functional parts of tool are produced of tool steel 19 436.3.

The in the framework of Master’s Studies developed project presents a technology- proposal for the production of a pressing tool for the manufacturing of parts from the sheet steel DD13. On the basis of a literary survey of problems of the component manufacturing through shearing, bending and the studies of heat treatment and applications of covering coat and calculation, manufacturing in the phase-shearing tool was proposed. The press GERB EDELHOFF 80 t was selected as the working device.