Fabrication of porous forsterite-spinel-periclase ceramics by transient liquid phase diffusion process for high-temperature thermal isolation

Aluminum metal matrix composites are materials frequently used in the automotive and aerospace industries due to their high strength-to-weight ratio, formability, corrosion resistance, and long-term durability. However, despite the unique properties of these materials, the lack of a reliable joining method has restricted their full potential in engineering applications. This article explores the effect of bonding time on transient liquid phase diffusion bonding of Al6061 containing 15 vol.% alumina particles using a 5 μm electrodeposited Ni-coating containing nano-sized alumina particles as the interlayer. Joint formation was attributed to the solid-state diffusion of Ni into the Al6061 alloy followed by eutectic formation and isothermal solidification at the joint interface. Examination of the joint region using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction showed the formation of eutectic phases such as Al3Ni, Al9FeNi, and Ni3Si within the joint zone. The results indicate that the addition of nano-size reinforcements into the interlayer can be used to improve joint strength. The joint strength recorded was 136 MPa at a bonding time of 10 min with a marginal increase in the shear strength when the bonding time is increased to 30 min.

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Oil Layer as Source of Hydrocarbon Emissions in SI Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2818198 ◽

1998 ◽

Vol 120 (3) ◽

pp. 669-677 ◽

Cited By ~ 2

Author(s):

K. Min ◽

W. K. Cheng

Keyword(s):

Liquid Phase ◽

Film Thickness ◽

Diffusion Process ◽

Penetration Depth ◽

Layer Thickness ◽

Hydrocarbon Emissions ◽

Source Strength ◽

Henry's Constant ◽

Oil Film ◽

Phase Diffusion

The role of lubrication oil film on the cylinder liner as a source of hydrocarbon emissions in spark-ignition engines is assessed. First, the “source strength” is examined via an analytical model of the gasoline vapor absorption/desorption process. The solution shows that depending on engine operating conditions, there are three regimes. The process could be (1) limited by the gas side diffusion process, (2) limited by the liquid phase diffusion process, with the absorbed fuel fully penetrating the oil layer thickness (thin oil film regime), and (3) again limited by the liquid phase diffusion process, but with the absorbed fuel penetration depth small compared to the oil layer thickness (thick oil film regime). In regime (1), the source strength (the integrated absorption or desorption flux over one cycle) is proportional to the inverse of the square root of the rpm, but independent of oil layer parameters. In regimes (2), the strength is proportional to the oil film thickness divided by the Henry’s constant. In regime (3), the strength is independent of the oil film thickness, but is proportional to the fuel penetration depth divided by the Henry’s constant. Then, the oxidation of the desorbed fuel (using iso-octane as fuel) is examined with a one-dimensional reaction/diffusion model. The novel feature of the model is that the desorbed fuel is being exposed to the piston crevice hydrocarbon, which is laid along the liner as the piston descends. At stoichiometric conditions, the oxidation of the crevice HC is reduced by the presence of the desorbed HC from the oil layer.

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Transient liquid phase diffusion bonding Al-6061 using nano-dispersed Ni coatings

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2011.04.051 ◽

2012 ◽

Vol 33 ◽

pp. 469-475 ◽

Cited By ~ 29

Author(s):

Kavian O. Cooke ◽

Tahir I. Khan ◽

Gossett D. Oliver

Keyword(s):

Liquid Phase ◽

Diffusion Bonding ◽

Transient Liquid Phase ◽

Phase Diffusion ◽

Al 6061

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Microstructure of Transient Liquid Phase Sintering Joint by Sn-Coated Cu Particles for High Temperature Packaging

International Symposium on Microelectronics ◽

10.4071/isom-2015-wp43 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 000449-000452 ◽

Cited By ~ 2

Author(s):

Xiangdong Liu ◽

Hiroshi Nishikawa

Keyword(s):

Shear Strength ◽

High Temperature ◽

Liquid Phase ◽

Applied Pressure ◽

Transient Liquid Phase ◽

Liquid Phase Sintering ◽

Thermally Stable ◽

Bonding System ◽

Cu Substrates ◽

Transient Liquid Phase Sintering

We develop a transient liquid phase sinter (TLPS) bonding using Sn-coated Cu micro-sized particles. With this bonding process, a thermally stable joint comprising Cu3Sn phase and a dispersion of ductile Cu particles can be obtained. The particle paste, which contained Cu particles with a thin Sn coating and terpineol, was used to join Cu substrates. The setup was bonded at 300 °C for 30s under an applied pressure of 10 MPa using a thermo-compression bonding system under a formic acid gas atmosphere for reducing the oxide layer on the Sn coating and the Cu substrate. After bonding, the TLPS joint showed a thermally stable microstructure with a good shear strength, which was fully consisted of Cu3Sn intermetallic compounds matrix and embedded ductile Cu particles. The kinetics of the microstructure transformation and high temperature reliability of the TLPS joint were investigated. After 300 °C isothermal aging for 200h, the shear strength and microstructure of the TLPS joints showed almost unchanged. The results demonstrate that joint with high-melting-point obtained by the TLPS bonding using Sn-coated Cu particle paste has the potential to fulfill the requirement of high temperature electronic packaging.

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