• Journal of Powder Materials
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• v.17 no.6
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• pp.489-493
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• 2010

Nickel-based and iron-based alloys have been developed and commercialized for a wide range of high performance applications at severely corrosive and high temperature environment. This alloy foam has an outstanding performance which is predestinated for diesel particulate filters, heat exchangers, and catalyst support, noise absorbers, battery, fuel cell, and flame distributers in burners in chemical and automotive industry. Production of alloy foam starts from high-tech coating technology and heat treatment of transient liquid-phase sintering in the high temperature. These technology allow for preparation of a wide variety of foam compositions such as Ni, Cr, Al, Fe on various pore size of pure nickel foam or iron foam in order for tailoring material properties to a specific application.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.347-347
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• 2010

We designed a new experimental set-up for measuring activity of heterogeneously catalyzed reactions. Using this set-up, we studied reduction of carbon dioxide by carbon dioxide reforming of methane (CRM) using nickel powder as catalyst. The properties of the catalysts were characterized by X-ray diffraction (XRD), Brunauer, Emmett & Teller (BET) surface area and X-ray photoelectron spectroscopy (XPS) techniques. The reactivity experiments were performed in the temperature range of $300\;-\;500^{\circ}C$. At reactivity experiment, result showed consumption of $CO_2$ and $CH_4$ with a 1:1 stoichiometry. At the same time, carbon monoxide and hydrogen were produced, which could be used for synthesizing fuels such as methanol. During the reaction, deposition of carbon on Ni was observed, which caused deactivation of the catalyst.

• Journal of Technologic Dentistry
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• v.7 no.1
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• pp.19-25
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• 1985

In oder to compare and measure bond strength of ceramometal system with use of ceramco porcelain powder including SnO2 and uni metal, Rexillium III, Vera Bond as non precious alloys manufactured for porecelain-metal restorations. Total 24 test sample were constructed. All Test sample were measured with a Mitutoyo micrometer graduated to 0.01mm. It is as follows measured of thickness 3.3mm(metal : 1.1mm, porcelain: 2.2mm), width 12mm, length 30mm(porcelain 12mm x 12mm), Compared maximum bending stress test. The results obtained were as follows: 1. Bond strength of each metal with ceramco porcelain powder showed statistical significance.(P<0.05) 2. Vera Bond and uni metal, uni metal and Rexillium III revealed no statistical Significance.(P>0.05) Vera Bond and Rexillium III showed statistical significance.(P<0.05) 3. The order of maximum bending stress was Rexillium III, uni metal, vera Bond. The order of bond strength ratio making bending stress was Vera bond, uni metal, Rexillium III.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.559-560
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• 2006

Powder forging is used for heavy-loaded parts (rings of rolling-contact bearings, gears etc.) production. Rolling contact fatigue is material property values of which characterize possibility of practical utilization of such parts. Rolling contact fatigue of some steels obtained out of prealloyed powders Astaloy CrM, Atomet 4601, Atomet 4901 and powder blends iron-carbon-nickel by hot forging is studied in the present paper. Effect of various kinds of heat and thermomechanical treatment on rolling contact fatigue is determined. Thermomechanical treatment provides optimal values of rolling contact fatigue. In this case steel structure contains up to 40% of retained metastable austenite which is transformed to martensite on trials. Thus typically crack is generated on residual pores and non-metallic inclusions instead of martensite zones in wrought steels.

• Journal of the Korean Ceramic Society
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• v.42 no.6 s.277
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• pp.432-436
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• 2005

Nickel powders synthesized by the reduction of hydrazine of nickel salts fiom diethanolamine(DEA) solution, and investigated the morphological characteristics of nickel powders with the addition of hydrazine, reaction temperature, the composition of mixed solvents. The addition of hydrazine in DEA solution largely affected on size control of nickel powders. Under $N_2H_4/Ni^{2+}$ molar ratio= 1.5 and 2.0 conditions, spherical nickel powders in the submicron range obtained, owing to higher the reduction rate. An increase of temperature increased the size of nickel particles. At $220^{\circ}C$ for 40 min, the nickel powders composed of polyhedral particles with high crystalline in the submicron range. The mixed volume ratio of TEA to DEA affected on the increase of particle size and the inhibition of agglomerate between particles.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.27 no.6
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• pp.303-308
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• 2017

The $FeCl_3$ waste solution used to etch various metals contains valuable metal such as nickel. In this study, we recovered as high purity nickel carbonate crystalline powders from nickel-containing etching waste solution after regeneration of iron chloride. Firstly we eliminated about of the iron impurities under the condition of pH 4 using 5 % NaOH aqueous solution and then removed the remaining impurities such as Ca, Mn and Zn etc. by using solvent extractant D2EHPA (Di-(2-ethylhexyl) phosphoric acid). Thereafter, nickel carbonate powder having a purity of 99.9 % or more was obtained through reaction with sodium carbonate in a nickel chloride solution.

• Resources Recycling
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• v.17 no.1
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• pp.59-65
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• 2008

The adsorption features of nickel ion in wastewater on manganese dioxide from spent batteries were investigated for its usage as an adsorbent. The aquatic behavior of nickel ion was characterized by MINTEQ program and the considered influential variables on the adsorption of nickel ion were its initial concentration, reaction temperature, the amount of adsorbent, and pH. The adsorption ratio of nickel ion decreased with increasing its initial concentration and thermodynamic estimation has been carried out based on the adsorption characteristics of nickel ion depending on temperature. In addition, the adsorption of nickel ion was shown to be promoted according to the amount of manganese dioxide and a lot of nickel ions were adsorbed as the solution pH was raised.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.05a
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• pp.81-81
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• 2002

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.165.1-165
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• 2002

• Journal of Powder Materials
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• v.6 no.2
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• pp.145-151
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• 1999

Nickel silicides ($Ni_5$Si$_2$, Ni$_2$Si and NiSi) have been synthesized by mechanical alloying (MA) of Ni-27.9at.9at%Si, Ni-33.3at% and Ni-50.0at% powder mixtures, respectively. From in situ thermal analysis, eash citical milling period for the formation of the three phases was observed to be 40.2, 34.9 and 57.5 min, at which there was a rapid increase in temperature. This indicates that rapid, self-propagating high-temperature synthesis (SHS) reactions were observed to produce the three phases during room-temperature high-energy ball milling of elemental powders. Each Ni silicide, Ni and Si, however, coexisted for an extended milling time even after the critical milling period. The powders mechanically alloyed after the critical period showed the rapid increase in microhardness. The Hv values were found to be higher than 1000kgf/mm$^2$. The formation of nickel silicides by mechanical alloying and the relevant reaction rates appeared to be influenced by the critical milling period and the heat of formation of the products involved ($Ni_5$Si$_2$$\rightarrow$-43.1kJ/mol.at., Ni$_2$Si$\rightarrow$-47.6kJ/mol.at., NiSi$\rightarrow$-42.4kJ/mol.at).