Processing and characterization of functionally graded materials through mechanical properties and glass transition temperature

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.

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

Journal of Composites Science ◽

10.3390/jcs5100254 ◽

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.

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Characterization of Fullerene / TriA-PI Composites

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.51.75 ◽

2006 ◽

Vol 51 ◽

pp. 75-80

Author(s):

Yasuaki Shinoda ◽

Ichiro Shiota ◽

Yuichi Ishida ◽

Toshio Ogasawara ◽

Rikio Yokota

Keyword(s):

Mechanical Properties ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Dynamic Mechanical Analysis ◽

Mechanical Analysis ◽

High Glass Transition Temperature ◽

Dynamic Mechanical ◽

Nano Size

TriA-PI is a newly developed phenylethnyl terminated polyimide. It exhibits excellent mechanical properties and processability with high glass transition temperature (Tg>300°C). Nano-size particles of fullerene were dispersed throughout a thermosetting polyimide Triple API (TriA-PI) to elevate the glass transition temperature. The increase of the glass transition temperature of the composites with the fullerene was confirmed by dynamic mechanical analysis (DMA).

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Studies on the Modification of Commercial Bisphenol-A-Based Epoxy Resin Using Different Multifunctional Epoxy Systems

Applied Mechanics ◽

10.3390/applmech2020023 ◽

2021 ◽

Vol 2 (2) ◽

pp. 419-430

Author(s):

Ankur Bajpai ◽

James R. Davidson ◽

Colin Robert

Keyword(s):

Mechanical Properties ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Bisphenol A ◽

Epoxy Resin ◽

Tensile Fracture ◽

Chemical Structures ◽

Amino Phenol ◽

Epoxy Systems

The tensile fracture mechanics and thermo-mechanical properties of mixtures composed of two kinds of epoxy resins of different chemical structures and functional groups were studied. The base resin was a bi-functional epoxy resin based on diglycidyl ether of bisphenol-A (DGEBA) and the other resins were (a) distilled triglycidylether of meta-amino phenol (b) 1, 6–naphthalene di epoxy and (c) fluorene di epoxy. This research shows that a small number of multifunctional epoxy systems, both di- and tri-functional, can significantly increase tensile strength (14%) over neat DGEBA while having no negative impact on other mechanical properties including glass transition temperature and elastic modulus. In fact, when compared to unmodified DGEBA, the tri-functional epoxy shows a slight increase (5%) in glass transition temperature at 10 wt.% concentration. The enhanced crosslinking of DGEBA (90 wt.%)/distilled triglycidylether of meta-amino phenol (10 wt.%) blends may be the possible reason for the improved glass transition. Finally, the influence of strain rate, temperature and moisture were investigated for both the neat DGEBA and the best performing modified system. The neat DGEBA was steadily outperformed by its modified counterpart in every condition.

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Synthesis, Properties, and Biodegradability of Thermoplastic Elastomers Made from 2-Methyl-1,3-propanediol, Glutaric Acid and Lactide

Life ◽

10.3390/life11010043 ◽

2021 ◽

Vol 11 (1) ◽

pp. 43

Author(s):

Lamya Zahir ◽

Takumitsu Kida ◽

Ryo Tanaka ◽

Yuushou Nakayama ◽

Takeshi Shiono ◽

...

Keyword(s):

Mechanical Properties ◽

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Glutaric Acid ◽

Triblock Copolymers ◽

Tensile Tests ◽

Thermoplastic Elastomers ◽

Proteinase K ◽

Synthesis Properties

An innovative type of biodegradable thermoplastic elastomers with improved mechanical properties from very common and potentially renewable sources, poly(L-lactide)-b-poly(2-methyl-1,3-propylene glutarate)-b-poly(L-lactide) (PLA-b-PMPG-b-PLA)s, has been developed for the first time. PLA-b-PMPG-b-PLAs were synthesized by polycondensation of 2-methyl-1,3-propanediol and glutaric acid and successive ring-opening polymerization of L-lactide, where PMPG is an amorphous central block with low glass transition temperature and PLA is hard semicrystalline terminal blocks. The copolymers showed glass transition temperature at lower than −40 °C and melting temperature at 130–152 °C. The tensile tests of these copolymers were also performed to evaluate their mechanical properties. The degradation of the copolymers and PMPG by enzymes proteinase K and lipase PS were investigated. Microbial biodegradation in seawater was also performed at 27 °C. The triblock copolymers and PMPG homopolymer were found to show 9–15% biodegradation within 28 days, representing their relatively high biodegradability in seawater. The macromolecular structure of the triblock copolymers of PLA and PMPG can be controlled to tune their mechanical and biodegradation properties, demonstrating their potential use in various applications.

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A review on solid state fabrication methods and property characterization of functionally graded materials

Materials Today Proceedings ◽

10.1016/j.matpr.2021.03.634 ◽

2021 ◽

Author(s):

Ranjeet Kumar Singh ◽

Vikas Rastogi

Keyword(s):

Solid State ◽

Functionally Graded Materials ◽

Functionally Graded ◽

Graded Materials ◽

Property Characterization

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Design of an n-type low glass transition temperature radical polymer

Polymer Chemistry ◽

10.1039/d0py01645d ◽

2021 ◽

Author(s):

Teng Chi ◽

Siddhartha Akkiraju ◽

Zihao Liang ◽

Ying Tan ◽

Ho Joong Kim ◽

...

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Glass Transition Temperature ◽

Synthesis And Characterization ◽

Design Synthesis

We document the design, synthesis, and characterization of the first low glass transition temperature, n-type (i.e., preferentially-reduced) radical polymer.

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