scholarly journals Tribological Characterization of Carbon Nanotube/Aluminum Functionally Graded Materials Fabricated by Centrifugal Slurry Methods

2021 ◽  
Vol 5 (10) ◽  
pp. 254
Author(s):  
Hideaki Tsukamoto
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotube ◽  
Functionally Graded Materials ◽  
Potassium Carbonate ◽  
High Performance ◽  
Functionally Graded ◽  
Graded Materials ◽  
Tribological Characterization ◽  
Al Matrix

Although carbon nanotube (CNT) is a promising material due to its excellent mechanical and functional properties, CNT has not been effectively used for high performance composites due to the degradation of its mechanical properties as a result of insufficient dispersibility of CNT in its matrix. In this study, CNT/aluminum (Al) matrix functionally graded materials (FGMs) were fabricated by centrifugal slurry methods. The dispersion of CNT was carried out with the solvent of dimethylacetamide (DMAs), and the dispersant of potassium carbonate (K2CO3) under ultrasonic sonication conditions. Tribological characteristics on the FGMs were investigated using a ball-on-disk tribometer. It was demonstrated that the presence of CNT contributed to an increase of the coefficients of friction and an enhancement of wear resistances.

Fabrication of Carbon Nanotube/ Aluminum Matrix Functionally Graded Materials Using Centrifugal Slurry Methods

2021 ◽  
Vol 878 ◽  
pp. 31-40
Author(s):  
Satoshi Namigata ◽  
Hideaki Tsukamoto
Keyword(s):  
Carbon Nanotube ◽  
Functionally Graded Materials ◽  
High Performance ◽  
Inorganic Salt ◽  
Aluminum Matrix ◽  
Functionally Graded ◽  
Graded Materials ◽  
Dispersing Agent ◽  
The Matrix ◽  
Al Matrix

Carbon nanotube (CNT) has received broad scientific and industrial attention due to their excellent mechanical and functional properties. However, CNT has not been effectively used for high performance composites because of degradation of mechanical properties due to insufficient dispersibility of CNT in the matrix. In this study, CNT/ aluminum (Al) matrix functionally graded materials (FGMs) have been focused on. The processes of dispersion of CNT have been carried out with the solvent of dimethylacetamide, and the dispersing agent of potassium carbonate, which is an inorganic salt, under ultrasonic sonication conditions. Centrifugal slurry methods have been applied to obtain gradient of content of CNT in CNT/ Al matrix FGMs. Tribological characteristics on CNT/ Al matrix FGMs have been investigated using a ball-on-disk tribometer. It has been demonstrated that CNT contributes to enhance wear resistances.

Incremental Melting and Solidification Process/Mechanical Characterization of Functionally Graded Al-Si Alloys

2008 ◽  
Vol 587-588 ◽  
pp. 400-404
Author(s):  
P. Pinto ◽  
L. Mazare ◽  
Delfim Soares ◽  
F.S. Silva
Keyword(s):  
Mechanical Properties ◽  
Functionally Graded Materials ◽  
Phase Distribution ◽  
Solidification Process ◽  
Functionally Graded ◽  
Graded Materials ◽  
Graded Material ◽  
Gradual Variation ◽  
Melting And Solidification

The Incremental Melting and Solidification Process (IMSP) is a relatively new field for material processing for the production of functionally graded materials. In this process a controlled liquid bath is maintained at the top of the component where new materials are added changing the components composition. Thus, a functionally graded material is obtained with a varying composition along one direction of the component. This paper deals with the influence of one of the process parameters, namely displacement rates between heating coil and mould, in order to evaluate its influence on both metallurgical and mechanical properties of different Al-Si alloys. Hardness and phase distribution, along the main castings axis, were measured. To better assess and characterize the process, two different Al-Si alloys with and without variation of chemical composition along the specimen were analysed. Results demonstrate that a gradual variation of metallurgical and mechanical properties along the component is obtained. It is also shown that Al-Si functionally graded materials can be produced by the incremental melting and solidification process. Results show that the displacement rate is very important on metallurgical and mechanical properties of the obtained alloy.

scholarly journals Tribological Characterization of Al2O3/TiC/Ni Functionally Graded Materials.

1998 ◽  
Vol 45 (3) ◽  
pp. 242-247 ◽  
Author(s):  
Yoshinari Miyamoto ◽  
Jhunshan Lin ◽  
Masaaki Yamamoto ◽  
Ryohei Tanaka ◽  
Kazunori Umeda ◽  
...  
Keyword(s):  
Functionally Graded Materials ◽  
Functionally Graded ◽  
Graded Materials ◽  
Tribological Characterization

Functionally Graded Polymeric Composites Having Micro-Tailored Structure Formed by Electric Field

Materials ◽  
2003 ◽  
Author(s):  
Geun Hyung Kim ◽  
Daniel K. Moeller ◽  
Yuri M. Shkel
Keyword(s):  
Mechanical Properties ◽  
Electric Field ◽  
Functionally Graded Materials ◽  
Applied Electric Field ◽  
Polymeric Composites ◽  
Functionally Graded ◽  
Graded Materials ◽  
Functionally Graded Composites ◽  
Liquid Suspensions ◽  
Redistribution Effect

A solid composite having locally micro-tailored structure can be produced by curing liquid polymeric suspensions in an electric field. The redistribution effect of the field-induced forces exceeds the effect of centrifugation, presently employed to manufacture functionally graded materials. Moreover, unlike centrifugational sedimentation, one can electrically rearrange the inclusions in desired targeted areas. The applied electric field can be employed to produce a composite having uniformly oriented structure or only modify the material in selected regions. This technology enables polymeric composites to be locally micro-tailored for given design objectives. We discuss electrical and rheological inteactions in liquid suspensions. Relationships between microstructure and mechanical properties of the obtained functionally graded composites are presented.

scholarly journals A fracture mechanics model for a crack problem of functionally graded materials with stochastic mechanical properties

2012 ◽  
Vol 468 (2146) ◽  
pp. 2939-2961 ◽  
Author(s):  
Licheng Guo ◽  
Zhihai Wang ◽  
Naotake Noda
Keyword(s):  
Mechanical Properties ◽  
Fracture Mechanics ◽  
Functionally Graded Materials ◽  
Small Sample ◽  
Functionally Graded ◽  
Phase Volume ◽  
Graded Materials ◽  
Volume Fractions ◽  
Mechanics Model ◽  
Crack Problems

This study aimed to develop a method to build a ‘bridge’ between the macro fracture mechanics model and stochastic micromechanics-based properties so that the macro fracture mechanics model can be expanded to the fracture mechanics problem of functionally graded materials (FGMs) with stochastic mechanical properties. An analytical fracture mechanics model is developed to predict the stress intensity factors (SIFs) in FGMs with stochastic uncertainties in phase volume fractions. Considering the stochastic description of the phase volume fractions, a micromechanics-based method is developed to derive the explicit probabilistic characteristics of the effective properties of the FGMs so that the stochastic mechanical properties can be combined with the macro fracture mechanics model. A thought for choosing the samples efficiently is proposed so that the stable probabilistic characteristic of SIFs can be obtained with a very small sample size. The probability density function of SIFs can be determined by developing a histogram from the generated samples. The present method may provide a thought to establish an analytical model for the crack problems of FGMs with stochastic properties.

Approximate Functionally Graded Materials for Multi-Material Additive Manufacturing

2018 ◽  
Author(s):  
Yuen-Shan Leung ◽  
Huachao Mao ◽  
Yong Chen
Keyword(s):  
Mechanical Properties ◽  
Additive Manufacturing ◽  
Functionally Graded Materials ◽  
Functionally Graded ◽  
Gradual Transition ◽  
Material Distribution ◽  
Graded Materials ◽  
Base Materials ◽  
Multiple Materials ◽  
Am Processes

Functionally graded materials (FGM) possess superior properties of multiple materials due to the continuous transitions of these materials. Recent progresses in multi-material additive manufacturing (AM) processes enable the creation of arbitrary material composition, which significantly enlarges the manufacturing capability of FGMs. At the same time, the fabrication capability also introduces new challenges for the design of FGMs. A critical issue is to create the continuous material distribution under the fabrication constraints of multi-material AM processes. Using voxels to approximate gradient material distribution could be one plausible way for additive manufacturing. However, current FGM design methods are non-additive-manufacturing-oriented and unpredictable. For instance, some designs require a vast number of materials to achieve continuous transitions; however, the material choices that are available in a multi-material AM machine are rather limited. Other designs control the volume fraction of two materials to achieve gradual transition; however, such transition cannot be functionally guaranteed. To address these issues, we present a design and fabrication framework for FGMs that can efficiently and effectively generate printable and predictable FGM structures. We adopt a data-driven approach to approximate the behavior of FGM using two base materials. A digital material library is constructed with different combinations of the base materials, and their mechanical properties are extracted by Finite Element Analysis (FEA). The mechanical properties are then used for the conversion process between the FGM and the dual material structure such that similar behavior is guaranteed. An error diffusion algorithm is further developed to minimize the approximation error. Simulation results on four test cases show that our approach is robust and accurate, and the framework can successfully design and fabricate such FGM structures.

Sign in / Sign up

Export Citation Format

Share Document