Medium-sized Parts Research Articles

LUCEFIN GROUP 16MnCr5 (1.7131), 16MnCrS5 (1.7139)

Abstract Lucefin Group 16MnCr5 and 16MnCrS5 are low-carbon, 1.2Mn-1Cr, alloy case-hardening steels that are used in the carburized or carbonitrided, and subsequently quench hardened and tempered condition. In general, these steels are used for small and medium size parts requiring high wear resistance and fatigue strength. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-864. Producer or Source: Lucefin S.p.A.

LUCEFIN GROUP 41Cr4 (1.7035), 41CrS4 (1.7039)

Abstract Lucefin Group 41Cr4 and 41CrS4 are medium-carbon, 1% chromium, direct hardening alloy steels that are also suitable for flame and induction hardening. These steels are low hardenability steels in the 0.40 to 0.42 mean carbon content classification. They are used for small and medium size parts that require a higher degree of strength and toughness. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength. It also includes information on forming, heat treating, machining, and joining. Filing Code: SA-860. Producer or source: Lucefin S.p.A..

Installation Design Capacity for Finish Treatment of Complex Profile Medium Size Parts by Unsupported Abrasive

Installation Design Capacity for Finish Treatment of Complex Profile Medium Size Parts by Unsupported Abrasive

Analytic Methods for Stress Analysis of Two-Dimensional Flat Anisotropic Plates With Notches: An Overview

The anisotropy of composite plates often poses difficulties for stress field analysis in the presence of notches. The most common methods for these analyses are: (i) analytical means (AM), (ii) finite element analysis (FEA), and (iii) semi-analytical means (SAM). In industry, FEA has been especially popular for the determination of stresses in small to medium size parts but can require a considerable amount of computing power and time. For faster analyses, one can use AM. The available solutions for a given problem, however, can be quite limited. Additionally, AM implemented in commercial computer software are scarce and difficult to find. Due to this, these methods are not widespread and SAM were proposed. SAM combine the (easy) implementation of complex problems from FEA and the computational efficiency from AM to reduce the difficulty on mathematical operation and increase computational speed with respect to FEA. AM, however, are still the fastest and most accurate way to determine the stress field in a given problem. Complex problems, however, e.g., finite width plates with multiple loaded/unloaded notches, require a significant amount of mathematical involvement which quickly discourages, even seasoned, scientists, and engineers. To encourage the use of AM, this paper gives a brief review of the mathematical basis of AM followed by a historic perspective on the expansions originating from this mathematical basis. Specifically the case of a two-dimensional anisotropic plate with unloaded cut-outs subjected to in-plane static load is presented.

Avaliação dos comportamentos mecânico e térmico de laminados de PPS/fibra de carbono processados em autoclave sob diferentes ciclos de consolidação

Usualmente, um dos processos mais utilizados para fabricação de componentes em termoplásticos estruturais é a moldagem por compressão a quente, porém restringindo-se na obtenção de peças de pequeno e médio porte. Tal restrição deve-se à limitação do tamanho das prensas utilizadas, principalmente pelo custo envolvido. Procurando ampliar a aplicação de compósitos termoplásticos, possibilitando a fabricação de peças maiores e com maior potencial de integração, pelo uso de infra-estrutura já disponível em processadores de compósitos, este trabalho aborda o processamento de laminados de poli(sulfeto de fenileno) (PPS) reforçado com fibra de carbono em autoclave, pelo uso de quatro diferentes ciclos de consolidação. Os laminados obtidos foram caracterizados por inspeção por ultrassom, análises de DSC para a determinação da cristalinidade e avaliação das propriedades mecânicas em flexão, compressão e cisalhamento interlaminar. Os resultados mostram que laminados obtidos com taxas de resfriamento mais lentas apresentam menor resistência e módulo em compressão, uma vez que o maior grau de cristalinidade (~30%) promove maior fragilização da matriz polimérica.

Pulse CVI-slurry joint process for manufacturing of small and medium size parts

In order to construct a suitable process for fabricating small and medium size CMC parts, attempts have been made to try to apply a pulse CVI-slurry joint process for making 3D carbon-fiber/SiC composites. The joint process consisted of slurry infiltration, polymer infiltration and pyrolysis, and pulse CVI. In the polymer infiltration and pyrolysis process, polycarbosilane was used as a preceramic polymer. The pulse CVI was carried out in a reaction temperature between 1323 K and 1423 K, using a source gas system of SiCl4-CH4-H2. The deposited phase varied with reaction temperature, gas concentration and reacting time. At 1373 K, a large amount of mass filling into a porous-matrix was observed. The flexural strength of the composite remarkably increased after the pulse CVI application. The joint process is effective for fabrication of thin and relatively simple shape parts.