Al2O3 Preforms with Gradient Porosity for Brake Disk Application

It has been known for many years that the incorporation of metallic particulates into a ceramic matrix can bring about the improvement of the mechanical properties of ceramics. Alumina/copper composites are well-known for their good frictional wear resistance, high resistance to thermal fatigue, high thermal conductivity as well as high absorption and dissipation of heat. The combination of the properties offered by alumina-copper composites makes them particularly interesting for wear applications in both automobile and aerospace industries. In the present paper we report on the design and production of a new class of alumina-copper functionally graded materials (FGM) which have technological potential for application in automotive brake disks. More specifically, this work deals with the development of the interpenetrating network structure of the FGM material. The manufacturing procedure was based on the gas-pressure infiltration of graded porous alumina preforms by liquid copper. The graded porous ceramic preforms with porosity ranging between 20 and 60% were made by casting foils made from slurries, the main components of which were alumina powder and rice starch powder (a pore forming agent), laminating these foils, subsequently burning-out the starch and last but not least performing a sintering process. A fundamental part of the presented investigations was to correlate the grain size of the alumina powders (Almatis, HVA FG and CT 1200 SG) and the pore size distribution, microstructure and selected mechanical and thermal properties of the porous ceramic preforms.

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Fabrication of 3Y-TZP/SUS304 functionally graded materials by slip casting; application of porous alumina molds

Materials Letters ◽

10.1016/s0167-577x(98)00112-8 ◽

1998 ◽

Vol 37 (6) ◽

pp. 312-319 ◽

Cited By ~ 13

Author(s):

Yeon-Gil Jung ◽

Sung-Churl Choi

Keyword(s):

Functionally Graded Materials ◽

Porous Alumina ◽

Slip Casting ◽

Functionally Graded ◽

Graded Materials

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Thermo-Elastic Analysis Of A Rotating Hollow Cylinder Made Of Arbitrary Functionally Graded Materials

Journal of Theoretical and Applied Mechanics ◽

10.1515/jtam-2015-0023 ◽

2015 ◽

Vol 45 (4) ◽

pp. 41-60

Author(s):

Mohammad Arefi ◽

Iman Nahas ◽

Majid Abedi

Keyword(s):

Radial Displacement ◽

Mechanical Analysis ◽

Functionally Graded ◽

Mechanical And Thermal Properties ◽

Elastic Analysis ◽

Graded Materials ◽

Hollow Structures ◽

Study Power ◽

Rotating Hollow Cylinder

AbstractThermo-mechanical analysis of the functionally graded orthotropic rotating hollow structures, subjected to thermo-mechanical loadings is studied in this paper. The relations were derived for both plane strain and plane stress conditions as a cylinder and disk, respectively. Non homogeneity was considered arbitrary through thickness direction for all mechanical and thermal properties. The responses of the system including temperature distribution, radial displacement and radial and circumferential stresses were derived in the general state. As case study, power law gradation was assumed for functionally graded cylinder and the mentioned results were evaluated in terms of parameters of the system such as non-homogeneous index and angular velocity.

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Toolpaths for additive manufacturing of functionally graded materials (FGM) parts

Rapid Prototyping Journal ◽

10.1108/rpj-01-2013-0011 ◽

2014 ◽

Vol 20 (6) ◽

pp. 511-522 ◽

Cited By ~ 19

Author(s):

Pierre Muller ◽

Jean-Yves Hascoet ◽

Pascal Mognol

Keyword(s):

Additive Manufacturing ◽

Path Planning ◽

Functionally Graded Materials ◽

Process Modeling ◽

Functionally Graded ◽

System Control ◽

Graded Materials ◽

Content Type ◽

Manufacturing Procedure ◽

Selection Of

Purpose – The purpose of this paper is to propose an evaluation of toolpaths for additive manufacturing of functionally graded materials (FGM) parts to ensure the manufacturing of parts in compliance with the desired material distribution. The selection of an appropriate path strategy is critical when manufacturing FGM parts. Design/methodology/approach – The selection of a path strategy is based on a process modeling and an additive laser melting (ALM) system control. To do that, some path strategies are selected, simulated and compared. Findings – The comparison of some paths strategies was applied on a study case from the biomedical field. Test-parts were manufactured and analyzed. Results show a good correlation between the simulated and the deposited material distributions. The evaluation of toolpaths based on the process modeling and the system control was validated. Originality/value – Nowadays, FGM parts manufactured with ALM processes are not functional. To move from these samples to functional parts, it is necessary to have a global approach of the manufacturing procedure centered on the path planning. Few methodologies of path planning are adapted to FGM parts but are still limited.

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Bending Response of Composite Material Plates with Specific Properties, Case of a Typical FGM "Ceramic/Metal" in Thermal Environments

Periodica Polytechnica Civil Engineering ◽

10.3311/ppci.11891 ◽

2018 ◽

Author(s):

Abdelrahmane Bekaddour Benyamina ◽

Bachir Bouderba ◽

Abdelkader Saoula

Keyword(s):

Composite Material ◽

Composite Structures ◽

Structural Engineering ◽

Rapid Development ◽

Functionally Graded ◽

Mechanical And Thermal Properties ◽

Graded Materials ◽

Thermal Environments ◽

Shear Function ◽

Electronic Chemical

The rapid development of composite materials and structures in recent years has attracted the increased attention of many engineers and researchers. These materials are widely used in aerospace, military, mechanical, nuclear, marine, optical, electronic, chemical, biomedical, energy sources, automotive fields, ship building and structural engineering industries. In conventional laminate composite structures, homogeneous elastic plate are bonded together to obtain improved mechanical and thermal properties. However, the abrupt change in material properties across the interface between the different materials can cause strong inter-laminar stresses leading to delamination, cracking, and other damage mechanisms at the interface between the layers. To remedy these defects, functionally graded materials (FGM) are used, in which the properties of materials vary constantly. The purpose of this paper is to analyze the thermomechanical bending behavior of functionally graded thick plates (FGM) made in ceramic/metal. This work presents a model that employed a new transverse shear function. The numerical results obtained by the present analysis are presented and compared with those available in the literature (classical, first-order, and other higher-order theories). It can be concluded that this theory is effective and simple for the static analysis of composite material plates with specific properties "Case of a typical FGM (ceramic/metal)" in thermal environments.

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Graded Powder Composites by Freeze Drying, Electrophoretic Deposition and Sintering

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.1533 ◽

2007 ◽

Vol 534-536 ◽

pp. 1533-1536 ◽

Cited By ~ 3

Author(s):

Eugene Olevsky ◽

Xuan Wang

Keyword(s):

Electrophoretic Deposition ◽

Freeze Drying ◽

Microwave Sintering ◽

Porous Ceramic ◽

Continuum Theory ◽

Functionally Graded ◽

Grain Structure ◽

Graded Materials ◽

Powder Composites

Two approaches for the fabrication of tailored powder composites with specially distributed pore-grain structure and chemical composition are investigated. Electrophoretic Deposition (EPD) followed by microwave sintering is employed to obtain functionally graded materials (FGM) by in-situ controlling the deposition bath suspension composition. Al2O3/ZrO2 and zeolite FGM are successfully synthesized using this technique. In order to fabricate an aligned porous structure, unidirectional freezing followed by freeze drying and sintering is employed. By controlling the temperature gradient during freezing of powder slurry, a unidirectional ice-ceramic structure is obtained. The frozen specimen is then subjected to freeze drying to sublimate the ice. The obtained capillary-porous ceramic specimen is consolidated by sintering. The sintering of the graded structure is modeled by the continuum theory of sintering.

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Effect of the Fillers Contents on the Chemical, Mechanical and Thermal Properties of Polymer Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.442.342 ◽

2010 ◽

Vol 442 ◽

pp. 342-348 ◽

Cited By ~ 2

Author(s):

A. Quddos ◽

S.M. Hussain ◽

Hafiz-ur-Rehman ◽

T. Abbas

Keyword(s):

Polymer Composites ◽

Process Condition ◽

Spectroscopic Studies ◽

Functionally Graded ◽

Extreme Condition ◽

Optimum Process ◽

Mechanical And Thermal Properties ◽

Graded Materials ◽

Ft Ir ◽

Ir Spectroscopic

Polymer composites are used in numerous applications. In spite of this fact, new developments are still under way to explore in other field of application of these materials and to tailor their properties for more extreme condition. A particular emphasis is focused on fillers content is summarized. Some steps towards the functionally graded materials are illustrated. The FT-IR spectroscopic studies revealed the information about curing of epoxy with fillers. It was observed that mechanical properties like tensile strength, hardness etc get enhanced up with filler contents. The effect of the different formulations were investigated and discussed for optimum process condition.

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