Effect of molybdenum addition on aluminium grain refined by titanium on its metallurgical and mechanical characteristics in the as cast condition and after pressing by the equal angular channel process

Zinc aluminum alloys are getting increasingly in use in industrial and engineering applications especially after the development of zinc alloys with higher aluminum content. These new developed zinc aluminum based alloys have high strength and hardness, improved creep and wear resistances and lower density. However they have the disadvantage of solidifying in dendritic structure with large grain size which adversely affects their mechanical strength, toughness and surface quality. Grain refinement of metals and alloys by rare earth elements has engaged the materials researchers for the last seven decades. In this paper the effect of molybdenum addition diagram to zinc 22 wt. % aluminum, ZA22, alloy grain refined by Ti-B at a rate of 0.1 wt. %, which corresponds to the peretictic point on the Al-Zn phase diagram in the as cast condition was carried out. The effect of the addition on the metallurgical and mechanical characteristics of the alloy were investigated and the obtained results are presented and discussed.

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Microstructural Features and Properties of Al-Cu-Mg Alloy Containing Silver and Cerium

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.316.533 ◽

2021 ◽

Vol 316 ◽

pp. 533-537

Author(s):

Pavel L. Reznik ◽

Boris V. Ovsyannikov

Keyword(s):

Heat Treatment ◽

Mechanical Characteristics ◽

Dendritic Segregation ◽

Scanning Calorimetry ◽

Electron Probe Micro Analyzer ◽

Melting Temperatures ◽

Heat Treatment Mode ◽

Cast Condition ◽

Component Phase ◽

Non Equilibrium

The article presents the results of an investigation of microstructural features and mechanical characteristics of Al-5.0Cu-0.5Mg alloy containing up to 0.4 wt. % Ag and up to 0.1 wt. % Ce. The experiment was conducted using optical microscopy, Scanning Electron Microscopy as well as an electron probe micro-analyzer and Differential Scanning Calorimetry. Samples in cast condition and after heat treatment were examined. The melting temperatures of non-equilibrium eutectics (non-equilibrium solidus), equilibrium solidus and liquidus were determined. The optimal temperature of the homogenizing heat treatment was determined, which was 500°C. Using this heat treatment mode resulted in the elimination of dendritic segregation and complete dissolution of silver in aluminum. Injection of cerium into the Al-Cu-Mg-Ag system during crystallization of the melt is accompanied by the formation of a coarse four-component phase, which has the morphology of polyhedrons, is on the grain boundaries. The estimation of the relation between microstructure characteristics and mechanical properties of the alloy has been made.

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Effect of Addition of Some Grain Refiners to Zinc-Aluminum 22, ZA22, Alloy on its Grain Size, Mechanical Characteristics in the Cast and after Pressing by the Equal Channel Angular Pressing, ECAP

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1105.172 ◽

2015 ◽

Vol 1105 ◽

pp. 172-177 ◽

Cited By ~ 1

Author(s):

Adnan I.O. Zaid ◽

Jehad A.S. AlKasasbeh ◽

S.M.A. Al-Qawabah

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Severe Plastic Deformation ◽

Equal Channel Angular Pressing ◽

Mechanical Characteristics ◽

The Other ◽

Angular Pressing ◽

Ecap Process ◽

Maximum Decrease ◽

Cast Condition

In this paper, the effect of addition of some grain refiners namely: molybdenum, titanium and titanium+boron to zinc-aluminum 22%, ZA22, alloy on its microstructure and mechanical characteristics is investigated in two conditions one in the cast condition and the other after pressing by the equal channel angular pressing, ECAP. Recently the ECAP process has been used to produce severe plastic deformation. It was found that addition of any of these elements to ZA22 alloy resulted in grain refinement of its structure both in the cast and after pressing by the ECAP conditions, being more pronounced after pressing by ECAP. The maximum decrease was %. Furthermore, it resulted in enhancement of its mechanical strength at, indicating softening of the alloy. Regarding the effect on its hardness, it decreased by th addition of either Mo or Ti+B. at any rate of Mo addition.

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Comparison between Mo Addition to Al Grain Refined by Ti and Ti+B on its Metallurgical and Mechanical Characteristics in the Cast and after ECAP Process Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.689.23 ◽

2016 ◽

Vol 689 ◽

pp. 23-28

Author(s):

Safwan M.A. Al-Qawabah ◽

Adnan I.O. Zaid ◽

Ahmad Qandil

Keyword(s):

Automobile Industry ◽

Mechanical Characteristics ◽

Pure Aluminum ◽

Weight Ratio ◽

High Strength ◽

Columnar Structure ◽

Process Conditions ◽

Ecap Process ◽

Commercially Pure ◽

Molybdenum Addition

Aluminum and its alloys are widely used materials; they are next to steel in use mainly in the automobile industry due to their high strength – to – weight ratio and corrosion resistance beside its other attractive properties. Against their attractive properties; they have the disadvantage of solidifying in columnar structure which tends to reduce their mechanical characteristics and surface quality. Therefore it became customary to grain refine them either by Ti or Ti+B to overcome this discrepancy. In this paper, comparison between Molybdenum addition to commercially pure aluminum grain refined by Ti and Ti+B on its grain size and mechanical characteristics both in the cast and after pressing by the ECAP process is investigated and the obtained results are presented and discussed.

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Microstructural characterization of a cast RENi5-based alloy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151714 ◽

1993 ◽

Vol 51 ◽

pp. 1176-1177

Author(s):

G. M. Micha ◽

L. Zhang

Keyword(s):

Electron Microscopy ◽

Rare Earth ◽

Microstructural Characterization ◽

Binary Compound ◽

Nickel Metal ◽

Cast Material ◽

Nickel Metal Hydride ◽

Transmission Electron ◽

Cast Condition

RENi5 (RE: rare earth) based alloys have been extensively evaluated for use as an electrode material for nickel-metal hydride batteries. A variety of alloys have been developed from the prototype intermetallic compound LaNi5. The use of mischmetal as a source of rare earth combined with transition metal and Al substitutions for Ni has caused the evolution of the alloy from a binary compound to one containing eight or more elements. This study evaluated the microstructural features of a complex commercial RENi5 based alloy using scanning and transmission electron microscopy.The alloy was evaluated in the as-cast condition. Its chemistry in at. pct. determined by bulk techniques was 12.1 La, 3.2 Ce, 1.5 Pr, 4.9 Nd, 50.2 Ni, 10.4 Co, 5.3 Mn and 2.0 Al. The as-cast material was of low strength, very brittle and contained a multitude of internal cracks. TEM foils could only be prepared by first embedding pieces of the alloy in epoxy.

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