Elaboration and Characterization of Zinc-Based Foams

For over a decade, metal foams have attracted a growing research interest because of the development of certain production processes. The advantages of metal foams most cited in the scientific literature are their low weight. However, one of the obstacles to their use on an industrial scale is the dispersion of their mechanical properties, in part because of their microstructural heterogeneity.

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Graphene Composites

Diffusion Foundations ◽

10.4028/www.scientific.net/df.23.57 ◽

2019 ◽

Vol 23 ◽

pp. 57-63 ◽

Cited By ~ 1

Author(s):

Chin Wei Lai

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

Polymer Composites ◽

Applied Research ◽

Scientific Literature ◽

Filler Content ◽

2D Materials ◽

Industrial Applications ◽

Research Interest ◽

Two Dimensional

This chapter reviews recent development of graphene-based polymer composites. The formation of graphene oxide and graphene are a vital two dimensional (2D) material has received a lot of research interest in commercialization aspect due to its excellent electrical, thermal as well as mechanical properties at very low filler content. In this manner, utilization of graphene-based polymer composites with different polymer matrixes have been attracted increasing attention in recent years for both fundamental studies and applied research into industrial applications in many fields. Herein, novel properties of polymer (epoxy, polystyrene, and PANI) / graphene composites will be reviewed along with detailed examples drawn from the scientific literature. Keywords: Graphene-based polymer composites, thermo-mechanical properties, two dimensional (2D) materials

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Characterization of Polypropylene Nanocomposite Structures

Journal of Engineering Materials and Technology ◽

10.1115/1.2400264 ◽

2006 ◽

Vol 129 (1) ◽

pp. 105-112 ◽

Cited By ~ 16

Author(s):

K. Kanny ◽

V. K. Moodley

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Material Properties ◽

Melt Blending ◽

Transmission Electron ◽

Low Weight ◽

Static Tensile ◽

Exfoliated Nanocomposite ◽

Nanocomposite Structures

This study describes the synthesis, mechanical properties, and morphology of nanophased polypropylene structures. The structures were manufactured by melt-blending low weight percentages of montmorillonite nanoclays and polypropylene thermoplastic. Both virgin and infused polypropylene structures were then subjected to quasi-static tensile, flexural, hardness and impact tests. Analysis of test data show that the mechanical properties increase with an increase in nanoclay loading up to a threshold of 2wt.%; thereafter, the material properties degrade. At low weight nanoclay loadings the enhancement of properties is attributed to the lower percolation points created by the high aspect ratio nanoclays. The increase in properties may also be attributed to the formation of intercalated and exfoliated nanocomposite structures formed at these loadings of clay. At higher weight loading, degradation in mechanical properties may be attributed to the formation of agglomerated clay tactoids. Results of transmission electron microscopy studies and scanning electron microscopy studies of the fractured surface of tensile specimens verify these hypotheses.

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Preparation and Characterization of Amorphous Al-Based Metal Foams

Materials Science Forum ◽

10.4028/www.scientific.net/msf.816.682 ◽

2015 ◽

Vol 816 ◽

pp. 682-687

Author(s):

Cong Bo Li ◽

Wei Wei Chen ◽

Lu Wang

Keyword(s):

Mechanical Properties ◽

Mechanical Behavior ◽

Intermetallic Compounds ◽

Dwell Time ◽

Metal Foam ◽

Metal Foams ◽

Plasma Sintering ◽

Spark Plasma ◽

Xrd Patterns

Amorphous Al-Cu-Ti metal foams with the porosity of 65% were prepared by spark plasma sintering with both the diameter and height of 10 mm. The SPS process was carried out under the pressure, the dwell time and the temperatures of 300 MPa, 5min and 623-673K, respectively. The microstructure and mechanical behavior of the amorphous Al-Cu-Ti metal foams were investigated. The results showed that sintering at high temperatures improved the crystallinity and adhesion between particles. The intermetallic compounds, i.e. Al-Ti, Al-Cu and Al-Cu-Ti were identified from the XRD patterns. It was found that weak adhesion and irregular shape of NaCl might reduce the mechanical properties. The highest strength of amorphous Al-based metal foam sintered at 653K, 300MPa was 7.97MPa.

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Preparation and Mechanical Properties of Graphene/Carbon Fiber-Reinforced Hierarchical Polymer Composites

Journal of Composites Science ◽

10.3390/jcs3010030 ◽

2019 ◽

Vol 3 (1) ◽

pp. 30 ◽

Cited By ~ 11

Author(s):

Jose Vázquez-Moreno ◽

Ruben Sánchez-Hidalgo ◽

Estela Sanz-Horcajo ◽

Jaime Viña ◽

Raquel Verdejo ◽

...

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Fiber Reinforced ◽

Reinforced Plastics ◽

Low Weight ◽

The Matrix ◽

Hierarchical Composites ◽

Superior Mechanical Properties ◽

Carbon Fiber Reinforced

Conventional carbon fiber-reinforced plastics (CFRP) have extensively been used as structural elements in a myriad of sectors due to their superior mechanical properties, low weight and ease of processing. However, the relatively weak compression and interlaminar properties of these composites limit their applications. Interest is, therefore, growing in the development of hierarchical or multiscale composites, in which, a nanoscale filler reinforcement is utilized to alleviate the existing limitations associated with the matrix-dominated properties. In this work, the fabrication and characterization of hierarchical composites are analyzed through the inclusion of graphene to conventional CFRP by vacuum-assisted resin infusion molding.

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Mechanical Characterization of Human Dentin: A Critical Review

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.541.75 ◽

2013 ◽

Vol 541 ◽

pp. 75-96 ◽

Cited By ~ 1

Author(s):

Ilaria Cappelloni ◽

Roberto Montanari

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Scientific Literature ◽

Mechanical Characterization ◽

Local Scale ◽

Functionally Graded ◽

Creep Stress ◽

Human Dentin ◽

Graded Material

In the last years, several experimental techniques have been improved to measure mechanical properties of human dentin. Dentin exhibits a behavior like a functionally graded material with properties dependent on tubule density and orientation. This work describes and critically analyzes the elastic, anelastic and plastic characteristics of dentin on the basis of scientific literature, in particular data of Youngs modulus, shear modulus, Poissons ratio, yield and ultimate stress, hardness, fatigue, fracture toughness, creep, stress relaxation and damping have been considered. Finally, a new indentation technique (FIMEC test) is proposed to characterize the mechanical properties of dentin on a local scale.

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Microstructural and fractographic characterization of B4C-Al cermets tested under dynamic and static loading

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154780 ◽

1989 ◽

Vol 47 ◽

pp. 562-563

Author(s):

Gyeung Ho Kim ◽

Mehmet Sarikaya ◽

D. L. Milius ◽

I. A. Aksay

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Fracture Toughness ◽

Static Loading ◽

Carbon Deposition ◽

Full Density ◽

Unique Combination ◽

Strong Component ◽

Reaction Products

Cermets are designed to optimize the mechanical properties of ceramics (hard and strong component) and metals (ductile and tough component) into one system. However, the processing of such systems is a problem in obtaining fully dense composite without deleterious reaction products. In the lightweight (2.65 g/cc) B4C-Al cermet, many of the processing problems have been circumvented. It is now possible to process fully dense B4C-Al cermet with tailored microstructures and achieve unique combination of mechanical properties (fracture strength of over 600 MPa and fracture toughness of 12 MPa-m1/2). In this paper, microstructure and fractography of B4C-Al cermets, tested under dynamic and static loading conditions, are described.The cermet is prepared by infiltration of Al at 1150°C into partially sintered B4C compact under vacuum to full density. Fracture surface replicas were prepared by using cellulose acetate and thin-film carbon deposition. Samples were observed with a Philips 3000 at 100 kV.

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Characterization of interfaces in CVD-coated nicalon fiber-reinforced SiC

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100154755 ◽

1989 ◽

Vol 47 ◽

pp. 556-557

Author(s):

K.L. More ◽

R.A. Lowden

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Chemical Vapor ◽

Chemical Vapor Infiltration ◽

Frictional Stress ◽

Fiber Reinforced ◽

Pull Out ◽

Carbon Coated ◽

Fiber Matrix

The mechanical properties of fiber-reinforced composites are directly related to the nature of the fiber-matrix bond. Fracture toughness is improved when debonding, crack deflection, and fiber pull-out occur which in turn depend on a weak interfacial bond. The interfacial characteristics of fiber-reinforced ceramics can be altered by applying thin coatings to the fibers prior to composite fabrication. In a previous study, Lowden and co-workers coated Nicalon fibers (Nippon Carbon Company) with silicon and carbon prior to chemical vapor infiltration with SiC and determined the influence of interfacial frictional stress on fracture phenomena. They found that the silicon-coated Nicalon fiber-reinforced SiC had low flexure strengths and brittle fracture whereas the composites containing carbon coated fibers exhibited improved strength and fracture toughness. In this study, coatings of boron or BN were applied to Nicalon fibers via chemical vapor deposition (CVD) and the fibers were subsequently incorporated in a SiC matrix. The fiber-matrix interfaces were characterized using transmission and scanning electron microscopy (TEM and SEM). Mechanical properties were determined and compared to those obtained for uncoated Nicalon fiber-reinforced SiC.

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