Finite volume and spectral methods applied to Pb-30%TI alloy solidification

Evaluation concepts for theGrowth Restriction Factor, Q, in multicomponent alloys are discussed and illustrated for ternary Al-Si-Ti alloys involving precipitation of primary intermetallic phases.

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Study of Convective Non-Newtonian Alloy Solidification in Molds by the PSIMPLER/Finite-Volume Method

Numerical Heat Transfer Part A Applications ◽

10.1080/10407782.2010.490171 ◽

2010 ◽

Vol 57 (12) ◽

pp. 936-953 ◽

Cited By ~ 15

Author(s):

Nelson O. Moraga ◽

Sandy del C. Ramírez ◽

Mauricio J. Godoy ◽

Pier'Angelo D. Ticchione

Keyword(s):

Finite Volume Method ◽

Finite Volume ◽

Alloy Solidification ◽

Volume Method

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Three-dimensional natural heat convection and ternary alloy solidification problems by finite volume geometric multigrid method

Numerical Heat Transfer Part A Applications ◽

10.1080/10407782.2020.1713685 ◽

2020 ◽

Vol 77 (6) ◽

pp. 632-648

Author(s):

Nelson O. Moraga ◽

Marcelo A. Marambio

Keyword(s):

Finite Volume ◽

Ternary Alloy ◽

Multigrid Method ◽

Three Dimensional ◽

Heat Convection ◽

Alloy Solidification ◽

Geometric Multigrid Method ◽

Natural Heat Convection ◽

Geometric Multigrid

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Shock consolidation of Ni-Ti alloy powder

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143730 ◽

1986 ◽

Vol 44 ◽

pp. 430-431

Author(s):

Naresh N. Thadhani ◽

Thad Vreeland ◽

Thomas J. Ahrens

Keyword(s):

Alloy Powder ◽

Amorphous Material ◽

Ti Alloy ◽

Two Phase ◽

Near Surface ◽

Optical Micrograph ◽

Shock Compaction ◽

Powder Particles ◽

Ti Powder ◽

Rapidly Solidified

A spherically-shaped, microcrystalline Ni-Ti alloy powder having fairly nonhomogeneous particle size distribution and chemical composition was consolidated with shock input energy of 316 kJ/kg. In the process of consolidation, shock energy is preferentially input at particle surfaces, resulting in melting of near-surface material and interparticle welding. The Ni-Ti powder particles were 2-60 μm in diameter (Fig. 1). About 30-40% of the powder particles were Ni-65wt% and balance were Ni-45wt%Ti (estimated by EMPA).Upon shock compaction, the two phase Ni-Ti powder particles were bonded together by the interparticle melt which rapidly solidified, usually to amorphous material. Fig. 2 is an optical micrograph (in plane of shock) of the consolidated Ni-Ti alloy powder, showing the particles with different etching contrast.

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Evolution of the microstructure of Cu(Ti)/SiO2 layers annealed in NH3

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100138634 ◽

1995 ◽

Vol 53 ◽

pp. 452-453

Author(s):

J. Liu ◽

N. D. Theodore ◽

D. Adams ◽

S. Russell ◽

T. L. Alford ◽

...

Keyword(s):

Thermal Stability ◽

Titanium Nitride ◽

Large Scale ◽

Standard Procedure ◽

Alloy Film ◽

Electron Beam Evaporation ◽

Copper Metallization ◽

Nominal Composition ◽

Ti Alloy ◽

Thermally Grown

Copper-based metallization has recently attracted extensive research because of its potential application in ultra-large-scale integration (ULSI) of semiconductor devices. The feasibility of copper metallization is, however, limited due to its thermal stability issues. In order to utilize copper in metallization systems diffusion barriers such as titanium nitride and other refractory materials, have been employed to enhance the thermal stability of copper. Titanium nitride layers can be formed by annealing Cu(Ti) alloy film evaporated on thermally grown SiO2 substrates in an ammonia ambient. We report here the microstructural evolution of Cu(Ti)/SiO2 layers during annealing in NH3 flowing ambient.The Cu(Ti) films used in this experiment were prepared by electron beam evaporation onto thermally grown SiO2 substrates. The nominal composition of the Cu(Ti) alloy was Cu73Ti27. Thermal treatments were conducted in NH3 flowing ambient for 30 minutes at temperatures ranging from 450°C to 650°C. Cross-section TEM specimens were prepared by the standard procedure.

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