Physical and Mechanical Properties of Mullite-Whisker Reinforced Alumina Composites

2007 ◽  
Vol 334-335 ◽  
pp. 325-328 ◽  
Author(s):  
Wei Kong Pang ◽  
Nobuo Tezuka ◽  
It Meng Low ◽  
E.G. Mehrtens ◽  
Bruno A. Latella
Keyword(s):  
Mechanical Properties ◽  
Thermal Analysis ◽  
Hot Isostatic Pressing ◽  
Physical And Mechanical Properties ◽  
Reaction Sintering ◽  
Alumina Matrix ◽  
Young’S Moduli ◽  
Solid Density ◽  
Alumina Composites

Reaction sintering and hot-isostatic-pressing (HIP) have been used for the compaction and densification of mullite-whisker-reinforced alumina composites. The effect of alumina matrix constraints on the in-situ transformation sequence in alumina-halloysite-AlF3 system was studied using differential thermal analysis. The physical and mechanical properties of the HIPed samples have been characterized in terms of bulk density, apparent solid density, porosity, Young’s moduli, flexural strength, hardness and the fracture toughness.

The Effect of Dispersion Method on the Mechanical Properties of Graphene Reinforced Alumina Composites

2018 ◽  
Vol 281 ◽  
pp. 93-98 ◽  
Author(s):  
Lu Wang ◽  
Jian Qiang Bi ◽  
Wei Li Wang ◽  
Xu Xia Hao ◽  
Xi Cheng Gao ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Bending Strength ◽  
Great Influence ◽  
Physical And Mechanical Properties ◽  
Structural Ceramics ◽  
Alumina Matrix ◽  
Dispersion Method ◽  
Mechanical Stirring ◽  
Alumina Composites ◽  
Scanning Electron

Due to the remarkable physical and mechanical properties of graphene, it is considered to be one of the most promising reinforcements for structural ceramics. In this paper, the composite material is compacted by hot pressing and the effects of mechanical stirring and ultrasonic on dispersion of graphene in alumina matrix were investigated, which was believed to have a great influence on the mechanical properties of the hot-pressed composites. It is found that from Scanning electron microscopy (SEM) observation. Compared with ultrasonic, the composite, in which graphene was dispersed by mechanical stirring, showed higher bending strength (555.1MPaVS432.3MPa) and fracture toughness (4.4MPa·m1/2VS 4.1MPa·m1/2). The result is much more promising to be employed in the designing and processing of graphene composites.

In Situ Fabrication of Particles Reinforced Al-Si-Al2O3 Composites by Hot Isostatic Pressing

2011 ◽  
Vol 284-286 ◽  
pp. 38-42 ◽  
Author(s):  
Ying Gao ◽  
Dei Gui Zhu ◽  
Ling Cheng ◽  
Hong Liang Sun ◽  
Qing Wang
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Hot Isostatic Pressing ◽  
Reaction Sintering ◽  
Test Results ◽  
Isostatic Pressing ◽  
In Situ Reaction ◽  
Heating Up ◽  
Sintering Processes

Particles reinforced Al-xwt.%Si-Al2O3(x=10,20) composites are fabricated through in situ reaction sintering of Al and SiO2powder by hot isostatic pressing. Outgassing process and the microstructure of composites under different sintering processes are studied.XRD analysis confirms that the best hot outgassing temperature is 500°C,in situ reaction achieves completely and samples A2 and B2 have better microstructure at 550°C then heating-up to 700°C only for 1h.The microstructure analysis indicates that the reinforcement particulates distribute uniformly in the aluminum matrix.The mechanical properties test results show that the tensile strength of A2 is higher than B2. whenx=10,the Al-Si-Al2O3composites have better performance.

A Novel In-Situ Nanoindentation Characterization of Phase Transforming Materials

2015 ◽  
Vol 1754 ◽  
pp. 19-24
Author(s):  
A. Alipour Skandani ◽  
R. Ctvrtlik ◽  
M. Al-Haik
Keyword(s):  
Mechanical Properties ◽  
Phase Transformation ◽  
Creep Compliance ◽  
Physical And Mechanical Properties ◽  
In Situ Methods ◽  
Negative Creep ◽  
Nanoindentation Instrument ◽  
Structural Instabilities

ABSTRACTMaterials with different allotropes can undergo one or more phase transformations based on the changes in the thermodynamic states. Each phase is stable in a certain temperature/pressure range and can possess different physical and mechanical properties compared to the other phases. The majority of material characterizations have been carried out for materials under equilibrium conditions where the material is stabilized in a certain phase and a lesser portion is devoted for onset of transformation. Alternatively, in situ measurements can be utilized to characterize materials while undergoing phase transformation. However, most of the in situ methods are aimed at measuring the physical properties such as dielectric constant, thermal/electrical conductivity and optical properties. Changes in material dimensions associated with phase transformation, makes direct measurement of the mechanical properties very challenging if not impossible. In this study a novel non-isothermal nanoindentation technique is introduced to directly measure the mechanical properties such as stiffness and creep compliance of a material at the phase transformation point. Single crystal ferroelectric triglycine sulfate (TGS) was synthetized and tested with this method using a temperature controlled nanoindentation instrument. The results reveal that the material, at the transformation point, exhibits structural instabilities such as negative stiffness and negative creep compliance which is in agreement with the findings of published works on the composites with ferroelectric inclusions.

Microstructure Development and Mechanical Properties of Ce-TZP/La- β-Alumina Composites

1992 ◽  
Vol 274 ◽  
Author(s):  
Takashi Fujii ◽  
Hironobu Muragaki ◽  
Hiraku Hatano ◽  
Shin-Ichi Hirano
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Hydrothermal Treatment ◽  
Fracture Strength ◽  
Sintered Body ◽  
Microstructure Development ◽  
Lanthanum Aluminate ◽  
Alumina Composites ◽  
In Situ Formation

ABSTRACTSimultaneous additions of lanthanum aluminate(LAL) and Al2O3 to Ce-TZP (12mol% CeO2-ZrO2) lead to the in-situ formation of lanthanum- β-alumina(LBA) platelets (∼1.0.μ m in width and 5 ∼10 μ m in length) in the Ce-TZP matrix during sintering. The composites showed a fracture toughness(SEPB method) of 9.5 MPa · m0.5 and fracture strength of 960 MPa. which are remarkably improved from Ce-TZP sintered body (8.5 MPa · m0.5 and 560 MPa).The composites also exhibit the no degradation by hydrothermal treatment.

CHARACTERIZATION AND APPLICATION OF CONDUCTING POLYMER COATED TEXTILES

2009 ◽  
Vol 23 (06n07) ◽  
pp. 1241-1247 ◽  
Author(s):  
LIJING WANG ◽  
TONG LIN ◽  
XUNGAI WANG
Keyword(s):  
Mechanical Properties ◽  
Physical Properties ◽  
Conducting Polymer ◽  
Physical And Mechanical Properties ◽  
Fibrous Materials ◽  
Conductive Coating ◽  
Coating Durability

This paper reports on some physical properties of a conducting polymer, polypyrrole, coated textiles. Polypyrrole was coated on textiles chemically through in-situ solution or vapor polymerisation to produce conducting textiles. The effects of the conductive coating on the physical and mechanical properties of the fibrous materials are presented. The coating durability and conductivity of the textiles have also been examined.

Nickel-Alumina Composites: In Situ Synthesis by a Displacement Reaction, and Mechanical Properties

1994 ◽  
Vol 365 ◽  
Author(s):  
Steven A. Jones ◽  
James M. Burlitch ◽  
Ersan Üstündag ◽  
Jeannie Yoo ◽  
Alan T. Zehnder
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Elastic Constants ◽  
High Performance ◽  
In Situ Synthesis ◽  
Displacement Reaction ◽  
Ductile Phase ◽  
Flexure Strength ◽  
Alumina Composites

ABSTRACTNickel-alumina composites have the potential to be high performance materials. Alumina, with its excellent oxidation resistance, combined with a ductile phase such as nickel may provide a tough material with a lower density and higher Young's modulus, overall, a higher specific modulus than typical Superalloys. Dense, interpenetrating Ni-Al2O3 composites were synthesized using a displacement reaction between NiO and aluminum. The resulting composites were characterized in terms of their mechanical properties such as hardness, flexure strength, fracture toughness and elastic constants. The synthesis, characterization, and mechanical properties, as well as the effect of the interpenetrating microstructure on the toughening mechanisms and other properties will be discussed.

Efficacy of Activated Carbon In Situ to Oil Palm Frond Paper for Active Packaging on Mechanical Properties

2012 ◽  
Vol 506 ◽  
pp. 607-610 ◽  
Author(s):  
N. Thongjun ◽  
Lerpong Jarupan ◽  
Chiravoot Pechyen
Keyword(s):  
Mechanical Properties ◽  
Activated Carbon ◽  
Moisture Content ◽  
Oil Palm ◽  
Physical And Mechanical Properties ◽  
Active Packaging ◽  
Modulus Of Rupture ◽  
Oil Palm Frond ◽  
Palm Frond

Oil palm frond pulp (OPF) was blended with activated carbon for the purpose of active packaging in this preliminary study. It was aimed to investigate the effect of in-situ activated carbon on physical and mechanical properties of the pulp handsheets made from OPF. Testing of property performances of the resulted handsheets included density, moisture content, thickness swelling, folding, tensile strength, %elongation, stiffness, and modulus of rupture. Ultimately, the intention is to use for prospected active packaging for fresh produce. OPF pulp was prepared by the kraft process. The pulp stock was mixed with different proportions of activated carbon (0, 10, 20, and 30% w/w). The results showed that an increased proportion of activated carbon decreased density and thickness selling, but had no effect on moisture content.

Formation and properties of nanocomposites made up from solid aspen wood, melamine-urea-formaldehyde, and clay

Holzforschung ◽  
2007 ◽  
Vol 61 (2) ◽  
pp. 148-154 ◽  
Author(s):  
Xiaolin Cai ◽  
Bernard Riedl ◽  
S.Y. Zhang ◽  
Hui Wan
Keyword(s):  
Mechanical Properties ◽  
Ball Mill ◽  
Urea Formaldehyde ◽  
Surface Hardness ◽  
Physical And Mechanical Properties ◽  
Water Soluble ◽  
Aspen Wood ◽  
Wood Polymer ◽  
Density Surface

Abstract Wood polymer nanocomposites were prepared from solid aspen wood, water-soluble melamine-urea-formaldehyde (MUF) resin, and silicate nanoclays. The nanofillers were ground with a ball-mill before being mixed with the MUF resin and impregnated into the wood. The water-soluble prepolymer was mixed with the nanoclays at a mixing speed of 3050 rpm for 20 min to form impregnation solutions. Wood was impregnated with resin, which polymerized in situ under certain conditions. The physical and mechanical properties of the composite and the effect of ball-milling treatment of nanofillers on these properties were investigated. Significant improvements in physical and mechanical properties, such as density, surface hardness, and modulus of elasticity, were obtained for specimens impregnated with MUF resin and nanoclay-MUF resin mixtures. Ball-mill treatment favors dispersion of the nanofillers into the wood, but also appears to interfere with particle-resin adhesion.

Structural, Physical and Mechanical Properties of Mg-Al Alloys Processed under CO2 Atmosphere

2012 ◽  
Vol 545 ◽  
pp. 247-250 ◽  
Author(s):  
Subramanian Jayalakshmi ◽  
Khoo Chee Guan ◽  
Kuma Joshua ◽  
Manoj Gupta
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Yield Strength ◽  
Magnesium Alloys ◽  
Physical And Mechanical Properties ◽  
Melting Process ◽  
Al Alloys ◽  
Compressive Yield Strength ◽  
Protective Atmospheres

Magnesium alloys are the lightest structural materials known that are increasingly replacing steel and aluminium. However, due to its flammable nature, protective atmospheres are employed during Mg-alloy production. In this novel work, Mg-Al alloys with ~3 and ~5 wt.% Al were processed in CO2atmosphere, so as to utilize the CO2during the melting process. The cast Mg-Al alloys were extruded and studied for their structural, physical and mechanical properties. Results showed improvements in mechanical properties such as hardness, tensile strength and compressive yield strength. The improvement in properties was attributed to thein situformation of Al4C3arising due to molten metal-carbon interaction. It is noteworthy that the incorporation of CO2during processing did not adversely affect the mechanical properties of the alloys. Further, the process is eco-friendly as it not only utilized CO2, but also eliminates use of harmful cover gases.

Sign in / Sign up

Export Citation Format

Share Document