Effective wave speeds in an SiC‐particle‐reinforced Al composite

1986 ◽  
Vol 79 (2) ◽  
pp. 239-248 ◽  
Author(s):  
H. M. Ledbetter ◽  
S. K. Datta
Keyword(s):  
Wave Speeds ◽  
Al Composite ◽  
Effective Wave ◽  
Sic Particle

Investigation on the influence of SiC particle parameters on the machinability of SiCp/Al composite

Vacuum ◽  
2021 ◽  
pp. 110340
Author(s):  
Ping Zhang ◽  
Xiujie Yue ◽  
Qiang Zhang ◽  
Chengguo Zong ◽  
Wei Lu ◽  
...  
Keyword(s):  
Al Composite ◽  
Particle Parameters ◽  
Sic Particle

Microstructure and Thermal Physical Properties of a β­SiCp/Al Composite for Electronic Packaging Produced by Powder Metallurgy

2017 ◽  
Vol 727 ◽  
pp. 565-570
Author(s):  
Yan Yan Shi ◽  
Xiao Gang Wang ◽  
Jun Tao Liu
Keyword(s):  
Physical Properties ◽  
Electronic Packaging ◽  
Volume Fraction ◽  
Coefficient Of Thermal Expansion ◽  
Weight Ratio ◽  
Pressing Method ◽  
Al Composite ◽  
The Relationship ◽  
Thermal Physical Properties ◽  
Sic Particle

The fabrication and thermal physical properties contain thermal conductivity (TC) and coefficient of thermal expansion (CTE) using 40%、50%、60% vol% β-SiC particle reinforced Al composite for electronic packaging respectively have been analyzed. The composites were produced by ball milling and pressing method. The composite which fabricated by tri-sized β-SiC particle with a weight ratio of 17:7:1,vol% of 50% and 60%.The dense and morphology were investigated. The relationship between volume fraction of β-SiC particle and thermal physical properties was discussed. Changed the volume fraction of β-SiC particle will led to a decreasing or increasing of TC and CTE. It found that values of TC and CTE were achieved their maximum balance when using tri-sized β-SiC particle of 160μm ,125μm as well as 38μm with a weight ratio of 17:7:1 and 50%vol of β-SiC particle reinforcing.

A Self-Consistent Approach to Multiple Scattering by Elastic Ellipsoidal Inclusions

1977 ◽  
Vol 44 (4) ◽  
pp. 657-662 ◽  
Author(s):  
S. K. Datta
Keyword(s):  
Multiple Scattering ◽  
Scattered Field ◽  
Homogeneous Function ◽  
Wave Number ◽  
Wave Speeds ◽  
Spherical Inclusions ◽  
Longitudinal And Shear Waves ◽  
Self Consistent ◽  
Effective Wave ◽  
Consistent Approach

This paper deals with the scattering of plane longitudinal and shear waves by a distribution of elastic ellipsoidal inclusions. The scattered field is determined correct to O(ε3) where ε is a nondimensional wave number, assumed small. Assuming then that the distribution of scatterer centers is random homogeneous function of position and using a self-consistent (“quasi-crystalline”) approximation effective wave speeds are determined for the case of preferred orientation. Various limiting cases, viz., spherical inclusions and voids, elliptic and penny-shaped cracks, and fluid-filled cavities, are derived.

Wave Propagation Through Elastically-Anisotropic Fluid-Saturated Porous Rocks

1989 ◽  
Vol 56 (4) ◽  
pp. 744-750 ◽  
Author(s):  
P. J. Digby ◽  
K. Walton
Keyword(s):  
Pore Space ◽  
Spherical Particles ◽  
Anisotropic Fluid ◽  
Coupling Coefficients ◽  
Porous Rocks ◽  
Dynamic Coupling ◽  
Wave Speeds ◽  
Averaged Equations ◽  
Effective Wave ◽  
Inviscid Compressible Fluid

An elastically-anisotropic sedimentary rock is modeled by a simple cubic packing of identical, contacting spherical particles. The connected pore space is filled with an inviscid, compressible fluid. A set of averaged equations is derived to relate the constitutive and dynamic coupling coefficients, and hence also the effective wave speeds in any given direction explicitly to the microstructural properties of the rock considered. Simple, explicit results are obtained when the propagation of either a purely longitudinal or a purely transverse wave is considered.

Compressible and Leaky Trains in Tunnels

1987 ◽  
Vol 201 (3) ◽  
pp. 209-215 ◽  
Author(s):  
A E Vardy ◽  
J A Fox
Keyword(s):  
Acoustic Wave ◽  
Wave Speed ◽  
Alternative Explanation ◽  
Blockage Ratio ◽  
Potential Influence ◽  
Wave Speeds ◽  
Effective Wave ◽  
Measured Pressure ◽  
Phase Differences

It is hypothesized that phase differences commonly observed between computed and measured pressure histories in railway tunnels may be caused in part by reduced acoustic wave speeds in the annular regions of flow alongside trains. Such reductions in wave speed are shown to be a possible consequence of the compressibility of trains and/or the leakage of air into and out of trains. These effects are shown to be capable in principle of reducing the effective wave speed by a factor of (1-β)1/2 where β denotes the train-tunnel area blockage ratio. The potential influence of reduced wave speeds due to these causes is shown to be much greater in short tunnels than in long tunnels. An alternative explanation for the discrepancies observed in long tunnels has yet to be found.

Wave Propagation Through Fluid Saturated Porous Rocks

1987 ◽  
Vol 54 (4) ◽  
pp. 788-793 ◽  
Author(s):  
K. Walton ◽  
P. J. Digby
Keyword(s):  
Pore Space ◽  
Low Frequency ◽  
Confining Pressure ◽  
Spherical Particles ◽  
Microstructural Properties ◽  
Porous Rocks ◽  
Wave Speeds ◽  
Expansion Technique ◽  
Effective Wave ◽  
Inviscid Compressible Fluid

A sedimentary rock is modeled by a random packing of identical spherical particles. The connected pore space is filled with an inviscid, compressible fluid. A low-frequency expansion technique is used to calculate the effective wave speeds explicitly in terms of the microstructural properties of the rock considered. The effect of both the pore fluid and the initial confining pressure to which the rock is subjected can be included in the calculations.

Effect of Current Density on Morphology and Corrosion Resistance of Anodized Coating on SiCp/2024 Al Composite

2007 ◽  
Vol 546-549 ◽  
pp. 661-666 ◽  
Author(s):  
Chun Lin He ◽  
Qing Kui Cai
Keyword(s):  
Corrosion Resistance ◽  
Current Density ◽  
Energy Dispersive Spectrometry ◽  
Surface Cracks ◽  
Sic Particles ◽  
Al Composite ◽  
Oxide Substrate ◽  
Current Densities ◽  
Reduced Rate ◽  
Sic Particle

The effects of current densities on the morphology and corrosion resistance of anodized coating formed on a SiCp/2024 Al metal matrix composite (MMC) in sulfuric acid solution were investigated by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and polarization curve. The results showed that the surface of the coating was not flat, and cracks existed when the current density increased to 20mA/cm2. The SiC particles could be oxidized during anodizing of the MMC. And the SiC particle anodized at a significantly reduced rate compared with the adjacent Al matrix. This gave rise to alumina film encroachment beneath the particle and occlusion of the partly anodized particle in the coating. As a consequence, the oxide/substrate interface became locally scalloped, and the anodized coating was non-uniform in thickness. Further, oxidation of SiC appeared to be associated with gas-filled cavities in the coating material. The size of cavities above the SiC particles increased obviously and the surface cracks developed when the current density increased. This shows that the anodized coating formed at higher current density has a structural feature with lower corrosion resistance. The polarization results indicated that the corrosion resistance of the coating decreases when the current density increases.

scholarly journals Effect of the Different High Volume Fraction of SiC Particles on the Junction of Bismuthate Glass-SiCp/Al Composite

Scanning ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-10
Author(s):  
Bin Wang ◽  
Shengguan Qu ◽  
Xiaoqiang Li
Keyword(s):  
Shear Strength ◽  
Volume Fraction ◽  
Coefficient Of Thermal Expansion ◽  
High Volume ◽  
Bonding Interface ◽  
Strength Testing ◽  
Infiltration Process ◽  
Sic Particles ◽  
Al Composite ◽  
Sic Particle

The in-house developed bismuthate glass and the SiCp/Al composites with different volume fractions of SiC particles (namely, 60 vol.%, 65 vol.%, 70 vol.%, and 75 vol.%) were jointed by vacuum hot-pressing process. The novel material can be used for the space mirror. The SiCp is an abbreviation for SiC particle. Firstly, the SiCp/Al composites with different vol.% of SiC particle were manufactured by using infiltration process. In order to obtain a stable bonding interface, the preoxide layers were fabricated on the surfaces of these composites for reacting with the bismuthate glass. The coefficient of thermal expansion (CTE) was carried out for characterizing the difference between the composites and bismuthate glass. The sealing quality of the composites and the bismuthate glass was quantified by using shear strength testing. The optical microstructures showed the particles were uniformly distributed in the Al matrix. The SEM image shows that a smooth oxidation layer was generated on the SiCp/Al composite. The CTE testing result indicated that the higher the vol.% of the particles in the composite, the lower the CTE value. The shear strength testing result disclosed that SiCp/Al composite with relatively low CTE value was favorable to obtain a bonding interface with high strength.

The microstructure of a TiB2/Ti-47 Al composite material

1989 ◽  
Vol 47 ◽  
pp. 674-675
Author(s):  
O. Popoola ◽  
A.H. Heuer ◽  
P. Pirouz
Keyword(s):  
Composite Material ◽  
Ion Beam ◽  
Chemical Properties ◽  
Intermetallic Alloys ◽  
Transmission Electron ◽  
Diamond Polishing ◽  
Al Composite ◽  
The Matrix ◽  
Argon Ion ◽  
And Chemical Properties

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.

Sign in / Sign up

Export Citation Format

Share Document