Effects of β-cooling rates on microstructural characteristics and hardness of Ti–5Al–5Mo–5V–3Cr–1Fe metastable β Ti alloy

Solidiﬁcation and microstructural characteristics of Al-5wt.%Mg-1.5wt.%Si-0.6wt.%Mn-0.2wt.%Ti alloy have been investigated in high pressure die casting. The average size of dendrites and fragmented dendrites of the primary α-Al phase formed in the shot sleeve is 43 m, and the globular α-Al grains formed inside the die cavity is 7.5 m. Solidification inside the die cavity also forms the lamellar Al-Mg2Si eutectic phase and the Fe-rich intermetallics. The size of the eutectic cells is about 10 m, in which the lamellar α-Al phase is 0.41 m thick. The Fe-rich intermetallic compound exhibits a compact morphology and is less than 2 m. Calculations using the Mullins and Sekerka stability criterion reveal that the solidiﬁcation of the primary α-Al phase inside the die cavity has completed before the spherical α-Al globules begin to lose their stability, but the α-Al grains formed in the shot sleeve exceed the limit of spherical growth and therefore exhibit a dendritic morphology.

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Effects of the microstructural characteristics of a metastable β Ti alloy on its corrosion fatigue properties

International Journal of Fatigue ◽

10.1016/j.ijfatigue.2013.04.010 ◽

2013 ◽

Vol 54 ◽

pp. 32-37 ◽

Cited By ~ 6

Author(s):

A. Cremasco ◽

E.S.N. Lopes ◽

F.F. Cardoso ◽

R.J. Contieri ◽

I. Ferreira ◽

...

Keyword(s):

Corrosion Fatigue ◽

Fatigue Properties ◽

Ti Alloy ◽

Microstructural Characteristics

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U--0.83 wt% Ti alloy: cooling rates of gamma-quenched alloy, resulting microstructure and response to aging

10.2172/4295006 ◽

1974 ◽

Author(s):

C.A. Javorsky

Keyword(s):

Ti Alloy ◽

Cooling Rates

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A multiscale investigation elucidating the structural complexities and electrochemical properties of layered–layered composite cathode materials synthesized at low temperatures

Physical Chemistry Chemical Physics ◽

10.1039/c9cp06165g ◽

2020 ◽

Vol 22 (10) ◽

pp. 5439-5448

Author(s):

Songyoot Kaewmala ◽

Narinthorn Wiriya ◽

Patcharapohn Chantrasuwan ◽

Visittapong Yordsri ◽

Wanwisa Limphirat ◽

...

Keyword(s):

Electrochemical Properties ◽

Structural Stability ◽

Cathode Materials ◽

Low Temperatures ◽

Composite Cathode ◽

Layered Composite ◽

Microstructural Characteristics ◽

Cooling Rates ◽

Heating And Cooling ◽

Composite Cathodes

0.5Li2MnO3·0.5LiCoO2 composite cathodes prepared using various heating and cooling rates under 600 °C reveal different microstructural characteristics that significantly impact their structural stability and electrochemical properties.

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Typical Microstructural Characteristics of Ti–5Al–5Mo–5V–3Cr–1Fe Metastable β Ti Alloy Forged in α + β Region

Acta Metallurgica Sinica (English Letters) ◽

10.1007/s40195-020-01115-y ◽

2020 ◽

Vol 33 (12) ◽

pp. 1601-1608 ◽

Cited By ~ 1

Author(s):

Zhiying Zheng ◽

Linjiang Chai ◽

Kang Xiang ◽

Weijiu Huang ◽

Yongfeng Wang ◽

...

Keyword(s):

Ti Alloy ◽

Microstructural Characteristics

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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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