Formation of fine skeletal Co–Ag by chemical leaching of Al–Co–Ag ternary alloys

Yamauchi, Isamu; Kawamura, H.; Nakano, Katsutoshi; Tanaka, Takeo

doi:10.1016/j.jallcom.2004.06.048

Cited by 13 publications

(13 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(1) Al-Co alloys (7,10,15,20 wt.% Co) were prepared by vacuum arc remelting. Highly directional microstructures were attained.…”

Section: Discussionmentioning

confidence: 99%

“…Al-Co alloys (7,10,15,20 wt.% Co or 3.3, 4.9, 7.5, 10.3 at.% Co, respectively) were fabricated by vacuum arc remelting (VAR). Appropriate mixtures of Al powder (finer than 44 µm, 99.5% purity) and Co powder (finer than 37 µm, 99.5% purity), were introduced into the furnace (placed in a water cooled copper crucible) and were melted at~(2200-2500)˝C.…”

Section: Raw Materials and Fabricationmentioning

confidence: 99%

See 1 more Smart Citation

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Lekatou

Sfikas

Petsa

et al. 2016

Metals

View full text Add to dashboard Cite

Hypereutectic Al-Co alloys of various Co contents (7-20 weight % (wt.%) Co) were prepared by vacuum arc melting, aiming at investigating the influence of the cobalt content on the microstructure and corrosion behavior. Quite uniform and directional microstructures were attained. The obtained microstructures depended on the Co content, ranging from fully eutectic growth (7 wt.% and 10 wt.% Co) to coarse primary Al 9 Co 2 predominance (20 wt.% Co). Co dissolution in Al far exceeded the negligible equilibrium solubility of Co in Al; however, it was hardly uniform. By increasing the cobalt content, the fraction and coarseness of Al 9 Co 2 , the content of Co dissolved in the Al matrix, and the hardness and porosity of the alloy increased. All alloys exhibited similar corrosion behavior in 3.5 wt.% NaCl with high resistance to localized corrosion. Al-7 wt.% Co showed slightly superior corrosion resistance than the other compositions in terms of relatively low corrosion rate, relatively low passivation current density and scarcity of stress corrosion cracking indications. All Al-Co compositions demonstrated substantially higher resistance to localized corrosion than commercially pure Al produced by casting, cold rolling and arc melting. A corrosion mechanism was formulated. Surface films were identified.

show abstract

“…(1) Al-Co alloys (7,10,15,20 wt.% Co) were prepared by vacuum arc remelting. Highly directional microstructures were attained.…”

Section: Discussionmentioning

confidence: 99%

Section: Raw Materials and Fabricationmentioning

confidence: 99%

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Lekatou

Sfikas

Petsa

et al. 2016

Metals

View full text Add to dashboard Cite

show abstract

“…It has also been reported that nanoporous Pt thin film on Si can be obtained by electrochemical dealloying of amorphous Pt x Si 1-x alloy in aqueous HF solutions [18]. Until now, dealloying has been observed in several ternary alloy systems including Ni-Cu-Mn [19], Cu-Al-Zn [20], AlCo-Ag [21,22], etc., all of which are ternary solid solutions precursors, yielding uniform microstructure by dealloying. However, research on the ternary alloy with multiphase consisting of different compositions has rarely been carried out.…”

Section: Introductionmentioning

confidence: 99%

Preparation and characterization of nanoporous Cu6Sn5/Cu composite by chemical dealloying of Al–Cu–Sn ternary alloy

et al. 2012

View full text Add to dashboard Cite

In this article, a new ternary Al-Cu-Sn alloy system has been exploited to fabricate nanoporous Cu 6 Sn 5 / Cu composite slices through chemical dealloying in a 20 wt% NaOH solution at an elevated temperature. The microstructure of the sliced nanoporous Cu 6 Sn 5 /Cu composite was characterized using x-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, and transmission electron microscopy. The experimental results show that multi-phase precursor alloy comprises a-Al, Sn, and h-Al 2 Cu phases. The new phase Cu 6 Sn 5 emerges through dealloying, and the as-dealloyed samples have three-dimensional (3D) structure composed of large-sized channels (hundreds of nanometers) and small-sized channels (tens of nanometers). Both the large-and small-sized pores are 3D, open and bicontinuous. The synergetic dealloying of a-Al and h-Al 2 Cu in the three-phase Al-CuSn alloy and fast surface diffusion of Cu atoms and Sn atoms result in the formation of Cu 6 Sn 5 /Cu composite with bimodal channel size distributions. In addition, the dealloying duration plays a significant role in the formation of Cu 6 Sn 5 and the length scales of the small-sized ligament/ channels at a settled temperature.

show abstract

“…Despite the significant research interest in the intermetallic compounds of Al, only few studies have been devoted to cobalt aluminides, possibly due to their limited, until recently, application potential. Co-aluminides may find applications as active heterogeneous catalysts [2], metallization layers in III-V semiconductor devices [3], to hydrogen fuel cell technologies [4] etc. Recently, the development of a new category of materials, that of Complex Metallic Alloys (CMAs)-Quasi Crystals (QCs) [5] has rekindled the interest in the Al-Co system: CMAs constitute a new class of intermetallic compounds with high structural complexity, giant unit cells containing from tens to more than a thousand atoms and lattice parameters of several nanometers [6].…”

Section: Introductionmentioning

confidence: 99%

Solid Particle Erosion of Aluminum In-Situ Reinforced with a Cobalt Aluminide

Lekatou¹

2017

Mater. Sci. Eng. Adv. Res

View full text Add to dashboard Cite

The present effort studies the comparative solid particle erosion behaviour of Al-Co alloys of various compositions in the AlAl 9 Co 2 side of the Al-Co phase diagram. The alloys have been prepared by vacuum arc melting. The main concept behind the selection of the Al-Al 9 Co 2 region of the Al-Co phase diagram was the attainment of a two-phase structure (Al + Al 9 Co 2 ) that could combine the beneficial attributes of Al 9 Co 2 , as a Complex Metallic Alloy in-situ reinforcement, with the ductility/toughness of Al, as a matrix to the brittle intermetallic.Hypereutectic Al-Co alloys of various Co contents (7, 10, 15 and 20 wt.% Co), as well as monolithic commercially pure Al, were prepared by vacuum arc melting. The alloys were subjected to solid particle erosion testing at two impact angles (60° and 90°). The test results were interpreted based on weight change measurements and scanning electronic microscopy. It was revealed that the governing mechanisms change as the impact angle and the reinforcement volume fraction change. It was shown that factors affecting the brittle/ductile character of the material, such as Al 9 Co 2 volume fraction, Al 9 Co 2 coarseness, Co dissolved in Al, play a primary role on the erosion response of the alloys. The Al-Co alloys showed higher wear rates than Al. The wear rate increased with Co and, consequently, Al 9 Co 2 increasing. The surface characteristics and degradation mechanisms are being discussed.

show abstract

Formation of fine skeletal Co–Ag by chemical leaching of Al–Co–Ag ternary alloys

Cited by 13 publications

References 11 publications

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Al-Co Alloys Prepared by Vacuum Arc Melting: Correlating Microstructure Evolution and Aqueous Corrosion Behavior with Co Content

Preparation and characterization of nanoporous Cu6Sn5/Cu composite by chemical dealloying of Al–Cu–Sn ternary alloy

Solid Particle Erosion of Aluminum In-Situ Reinforced with a Cobalt Aluminide

Contact Info

Product

Resources

About