Toughness
Mostrando 25-36 de 299 artigos, teses e dissertações.
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25. Experimental analysis of load capacity in beams with steel fiber reinforcement on the compression face
Resumo A utilização de fibras de aço no concreto visa aumentar principalmente a tenacidade, em função da aderência das fibras à matriz cimentícia. Entretanto como existem diversas tipologias de fibras de aço, as principais diferenças estão no fator de forma (relação entre comprimento e diâmetro), na geometria das fibras, e, na caracterização
Rev. IBRACON Estrut. Mater.. Publicado em: 2019-02
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26. Shredders prefer soft and fungal-conditioned leaves, regardless of their initial chemical traits
RESUMO Nós investigamos em experimento de campo e de laboratório os efeitos das características foliares e condicionamento microbiano de duas espécies de árvores na abundância, biomassa e preferência alimentar de um fragmentador típico. No experimento de campo, comparamos a associação do Phylloicus (Calamoceratidae, Trichoptera) entre duas espécie
Iheringia, Sér. Zool.. Publicado em: 14/01/2019
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27. Densification and microstructure of Si3N4-TiN ceramic composites
Abstract Silicon nitride is a ceramic material widely used in various structural applications at high temperatures owing to its excellent combination of mechanical and thermal properties. To increase the application of Si3N4, many researches have been developed to improve its fracture toughness and processing conditions. In this study, the sintering and micr
Cerâmica. Publicado em: 2019-01
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28. Izod impact energy study of re-forced polisher matrix compounds with curaous fibers aligned and epoxy matrix reinforced with piassava fibers
ABSTRACT Polymer matrix composites have been applied in components such as helmets and shielding for which toughness is a major requirement. Natural fiber presents interfacial characteristics with polymeric matrices that favor a high impact energy absorption by the composite structure. The objective of this work was then to assess the Izod impact resistance
Matéria (Rio J.). Publicado em: 06/12/2018
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29. Influence of Cryogenic Treatment on the Tribological Behaviour of AISI H21 Tool Steel
The aim of the present work was to find out the optimum cryosoaking duration of deep cryogenic treatment to reduce the wear rate. The AISI H21 hot work tool steel specimens were hardened at 1195 ºC, cryotreated at -185 ºC for 6 to 30 h, double tempered at 540 ºC and soft tempered at 100 ºC. The hardness, impact toughness, wear rate and microstructural ch
Mat. Res.. Publicado em: 29/10/2018
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30. Effect of Hot Deformation on Microstructure, Hardness and Precipitation Kinetics in a C350 Maraging Steel Modified by Titanium Addition
Maraging steels are alloys with a good balance between strength and fracture toughness. These properties are obtained by quenching and aging treatments, where the precipitation of intermetallic compounds is promoted in a martensitic matrix. In this context, this paper aims to evaluate the effect of hot deformation on microstructure, kinetics and formation of
Mat. Res.. Publicado em: 17/09/2018
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31. Microstructure, Mechanical Properties and in vitro Biological Behavior of Silicon Nitride Ceramics
The bioinert surface of silicon nitride ceramics led us to investigate the additions of SiO2, CaO and Al2O3 in order to aid the liquid phase sintering and improve the mechanical properties and biological behavior of the final materials. The sintered materials reached ca. 97% of theoretical density and total α→β-Si3N4 transformation. The samples had relat
Mat. Res.. Publicado em: 13/09/2018
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32. The effect of the austenite grain refinement on the tensile and impact properties of cast Hadfield steel
This paper studied the effect of the austenite grain refinement on the tensile and impact properties of a cast Hadfield steel (12 % Mn, 1.2 %C and 0.65 % Si). The austenite grain refinement was obtained by hafnium inoculation. Microstructural characterization showed that the Hf-refined cast Hadfield steel featured a grain size of 600 µm, while the non-refin
Mat. Res.. Publicado em: 02/08/2018
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33. Evaluation of Fracture Toughness of Ultraviolet-Irradiated Polycarbonate Using the Essential Work of Fracture Method
The essential work of fracture (EWF) method provides useful parameters to characterize the fracture toughness of polymers exposed to degrading environments under conditions associated with plane-stress state of failure. Exposure of polymeric engineering materials to ultraviolet (UV) radiation may produce macromolecular changes that impair their fracture toug
Mat. Res.. Publicado em: 26/07/2018
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34. Determinación de la tenacidad a la fractura J en laminados fibra-metal del tipo CARALL con láminas de aluminio 6061 y 1050
ABSTRACT Determination of fracture toughness in hybrid composites, fiber-metal laminates, FML (Fiber Metal Laminates) is very important to perform an analysis of structural integrity to estimate damage tolerance and residual strength of the material against the propagation of a crack This evaluation should be done in both naval and aircraft structures using
Matéria (Rio J.). Publicado em: 19/07/2018
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35. Estudio del comportamiento de fundición CADI sometida a FCR
ABSTRACT Ductile Iron (DI) is a development of the iron alloys introduced in the ´50s, with free graphite in the form of nodules. Austempered Ductile Iron (ADI) is a development of DI later introduced, consisting on austempering heat treatment in order to obtain a high strength and high toughness material. Carbidic Austempered Ductile Iron (CADI) is a more
Matéria (Rio J.). Publicado em: 19/07/2018
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36. Obtención de aceros de baja aleación con diferentes contenidos de Ni y similares microestructuras y propiedades mecánicas
ABSTRACT Low alloy steels are used in many applications in the oil and gas industry. The addition of Ni in these steels improves their low temperature fracture toughness and hardenability, with a low penalty on weldability. However, ISO 15156-2 standard restricts Ni content up to a 1 wt% limit, requiring additional and expensive tests if higher Ni steels are
Matéria (Rio J.). Publicado em: 19/07/2018