• Korean Journal of Metals and Materials
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• v.48 no.3
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• pp.241-247
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• 2010

In order to develop the vacuum distillation process of magnesium alloy scrap, a fundamental study on the evaporation behavior of magnesium alloy (AM50) scrap melt was carried out. Melt temperature, pressure, reaction time, and initial specific surface area of melt were considered as experimental variables. The evaporation rate of magnesium increased with the increase of melt temperature and initial specific surface area of melt, and with the decrease of the pressure. The activation energy of magnesium evaporation reaction calculated by an Arrhenius plot decreased with the decrease of the pressure and with the increase of the initial specific surface area of melt. An empirical equation was derived for the evaporation rate of magnesium from AM50 alloy melt.

• Resources Recycling
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• v.29 no.5
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• pp.3-14
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• 2020

Magnesium is the third most abundant structural metal after aluminum and iron. Magnesium is the lightest metal in the common metals. It has a density 33 % less than aluminum and 77% lower than steel. However, the primary magnesium production process is highly energy intensive. The recycling of magnesium scrap reduces the energy consumption and environmental burden, comparing to the primary metal production. However, the amount of recovered metal from scrap is limited because of the difficulties to remove the impurities in the scrap. This work provides an overview of the magnesium production and recycling process.

• Korean Journal of Metals and Materials
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• v.46 no.1
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• pp.13-19
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• 2008

To develop a recycling process of magnesium alloy scrap, a fundamental study on the distillation of magnesium alloy melt was carried out. Melt temperature, vacuum degree and reaction time were considered as experimental variables. The amount of vaporized magnesium melt per unit surface area of melt increases with the increase of melt temperature, reaction time and vacuum degree. The vapor condensed at the tip of water cooling Cu-condenser as a form of pine cone. Magnesium and zinc were vaporized easily from the melt. However, It's difficult to separate magnesium and zinc by vacuum distillation because vapor pressure of zinc is similar to one of magnesium. The contents of aluminum, manganese and iron, etc. in residual melt increase due to the decrease of magnesium and zinc content after the distillation of magnesium alloy.

• Resources Recycling
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• v.20 no.1
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• pp.69-79
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• 2011

Recently, magnesium alloys are in the spotlight as a promising materials in the fields of automobile parts and electronic appliances due to their merits representing light weight, high specific strength, damping property, shielding of electromagnetic wave and so on. However, magnesium alloys show a poor formability at room temperature because magnesium has HCP crystal structure with limited slip planes and strong basal texture is formed during plastic deformation process such as rolling and extrusion. Therefore, many R&D efforts have been paid for improvement of formability through grain refinement, texture control and various forming technologies. This paper is giving an overview about recent achievements on control of microstructures, forming technologies and magnesium scrap recycling.

• Resources Recycling
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• v.30 no.1
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• pp.26-34
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• 2021

Titanium is the fourth most abundant structural metal, after aluminum, iron, and magnesium. However, it is classified as a 'rare metals', because it is difficult to smelt. In particular, the primary titanium production process is highly energy-intensive. Recycling titanium scraps to produce ingots can reduce energy consumption and CO2 emissions by approximately 95 %. However, the amount of metal recycled from scrap remains limited of the difficulty in removing impurities such as iron and oxygen from the scrap. Generally, high-grade titanium and its alloy scraps are recycled by dilution with a virgin titanium sponge during the remelting process. Low-grade titanium scrap is recycled to ferrotitanium (cascade recycling). This paper provides an overview of titanium production and recycling processes.

• Journal of the Korean Society of Safety
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• v.21 no.1 s.73
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• pp.65-71
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• 2006

Flame retardancy and mechanical properties of polyolefinic mixed waste plastics/filler composites were investigated by using inorganic flame retardant(magnesium hydroxide) and PUB(polyurethane block) powder generated from cryogenic insulation process. All composites were obtained by extrusion and after compression molding. The effect of PUB powder on the properties of the composites was studied by tensile and izod impact test, morphology studies and flammability as LOI and UL94 vertical burning test and smoke density. The objective of this work is to obtain good mechanical properties from recycled PP composites with $Mg(OH)_{2}/PUB$ powder as fillers and optimum cost-performance balance, in addition to flame retardant characteristics.

• Resources Recycling
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• v.22 no.3
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• pp.73-80
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• 2013

Metal prices are rapidly rising due to increasing demand of metals and limited available resources according to the industrial requirement. As a result, securing a stable supply of these metal resources has been recognized as a core element of national competitiveness and sustained economic growth. In the case of magnesium and its alloys which are entirely depending on import, low-grade magnesium scraps from end-of-life vehicles and 3C(Camera, Computer, Communication) parts and magnesium wastes such as sludge and dross generated during melting process are hardly recycled. Accordingly, the development and commercialization of recycling technology of low-grade magnesium scrap is desperately needed to improve efficiency of resource circulation and to establish the required proprietary of resource metal supply and demand. In this study, papers and patents on recycling technologies of waste magnesium were analyzed. The range of search was limited in the open patents of USA (US), European Union (EP), Japan (JP), Korea (KR) and SCI journals from 1974 to 2012. Patents and journals were collected using key-words searching and filtered by filtering criteria. The trends of the patents and journals was analyzed by the years, countries, companies, and technologies.