Interdiffusion and solid state reactions in powder mixtures—one more model

Гусак, А. М.; Lucenko, Gregory

doi:10.1016/s1359-6454(98)00054-8

Cited by 20 publications

(8 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Factors favorable for densification in heating prior to liquid formation are also favorable for densification during LPS. Despite the prevalence of practical systems based on mixed powder sintering, only a few quantitative models predict densification and microstructure changes [104][105][106]. The parameters that influence densification include particle size and green density as found in solid-state sintering.…”

Section: Preliquid Stagementioning

confidence: 99%

Review: liquid phase sintering

2009

View full text Add to dashboard Cite

Liquid phase sintering (LPS) is a process for forming high performance, multiple-phase components from powders. It involves sintering under conditions where solid grains coexist with a wetting liquid. Many variants of LPS are applied to a wide range of engineering materials. Example applications for this technology are found in automobile engine connecting rods and high-speed metal cutting inserts. Scientific advances in understanding LPS began in the 1950s. The resulting quantitative process models are now embedded in computer simulations to enable predictions of the sintered component dimensions, microstructure, and properties. However, there are remaining areas in need of research attention. This LPS review, based on over 2,500 publications, outlines what happens when mixed powders are heated to the LPS temperature, with a focus on the densification and microstructure evolution events.

show abstract

Section: Preliquid Stagementioning

confidence: 99%

Review: liquid phase sintering

2009

View full text Add to dashboard Cite

show abstract

“…Both methods were combined and allow account of interface kinetics and nucleation in the concentration gradient. 9,10 They contain the following implicit assumptions:…”

Section: Two-phase Growthmentioning

confidence: 99%

“…If the left terminal phase is fixed at its right boundary (the interphase velocity equals zero: X 0 ðtÞ¼0), the volume velocities in the phases forming the mixture are equal [follows from Eq. (10)]. The deviation of chemical potential at interfaces can be expressed by the deviation of concentration using Eq.…”

Section: Appendix C: Steady-state Growthmentioning

confidence: 99%

Chemical interdiffusion in binary systems; interface barriers and phase competition

Danielewski

Wierzba

Гусак

et al. 2011

Journal of Applied Physics

View full text Add to dashboard Cite

The problem of simultaneous growth and competition of intermediate phases during reactive diffusion is formulated and solved. In this paper, we compare existing models of steady state reaction diffusion and introduce the new one basing on the bi-velocity method. We extend old problem and propose method based on material (lattice) fixed frame of reference. It allows computing the material velocity in the reacting system in which reactions at several moving interfaces occur. All reactions lead to the lattice shift due to the difference of intrinsic diffusivities and different molar volumes. The following peculiarities are taken into account: (1) the deviation from local equilibrium at all interfaces; (2) the mobilities of the components in the bulk and interphase zone; and (3) the molar volumes of the components. We show the kinetic of the reactions, the non parabolic regime, the multiphase scale growth and present the practical application of the method. V

show abstract

“…Similarly, the higher effective concentration of Au at the growth interface adjacent to Au results in Au 4 Al ͑⌬HЉ = −19.0 kJ/ mol͒ readily forming ͑Table I͒. Although ⌬H is a reasonable indirect measure of Gibbs'-free energy release during interfacial reactions, the role of nucleation barriers and kinetics 27,45,[48][49][50] are of most consequence in predicating the phase assemblage in the bond. Pretorius et al 27 stated that the more atoms in a unit cell, the more difficult and less energetically favorable it is to crystallize.…”

Section: -5mentioning

confidence: 99%

A micromechanism study of thermosonic gold wire bonding on aluminum pad

Liu

Silberschmidt

et al. 2010

Journal of Applied Physics

View full text Add to dashboard Cite

A micromechanism of thermosonic gold wire bonding was elaborated by examining its interfacial characteristics as a result of the bonding process, including the fragmentation of the native aluminum oxide layer on Al pads, and formation of initial intermetallic compounds ͑IMCs͒. It is found that the existence of an approximately 5 nm thick native oxide layer on original Al pads has a significant effect on the bonding, and the nucleation of IMCs during the bonding process must overcome this relatively inert thin film. Bonding strength was fundamentally determined by the degree of fragmentation of the oxide films, through which the formation of IMCs can be initiated due to the direct contact of the metal surfaces to be bonded. The extent of fracture the oxide layer was strongly influenced by the level of ultrasonic power, as at its high level alumina fragmentation becomes pervasive resulting in contiguous alloy interfaces and robust bonds. The IMCs formed at the interfaces were identified as Al 4 Al and AuAl 2 with a thickness of 150-300 nm. The formation mechanism of such IMCs was explained by the effective heat of formation theory.

show abstract

Interdiffusion and solid state reactions in powder mixtures—one more model

Cited by 20 publications

References 10 publications

Review: liquid phase sintering

Review: liquid phase sintering

Chemical interdiffusion in binary systems; interface barriers and phase competition

A micromechanism study of thermosonic gold wire bonding on aluminum pad

Contact Info

Product

Resources

About