• Journal of the Korean institute of surface engineering
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• v.27 no.6
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• pp.319-326
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• 1994

The effects of electrolysis conditions on the composition and preferred orientation of Ni-Fe alloy were studied using the sulfate-chloride baths paddle agitated. Cathode current efficiency is higher in the deposits from bath 2 than that of deposits from bath 1. The Fe content of alloy deposits from bath 2 is nearly constant(19∼21wt.%) in the wide range of current density, while it decreases noticeably with current density in the deposits from bath 1. The variation of Fe content at the edge of specimen is lower in deposits from bath 2 than those from bath 1. The alloy deposits show (111) & (200) preferred orientation for the deposits from bath 1 and bath 2 respectively.

• Journal of the Korean institute of surface engineering
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• v.33 no.5
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• pp.339-348
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• 2000

The study was conducted on the effect of bath composition on the surface appearance, the hardness and the crystal orientation of zinc electrodeposits from the chloride bath. (1) The hardness of the zinc electrodeposits from the chloride bath was increased by suppressing mass transfer of zinc through adding the organic additives and the chlorine ion in the electrolyte. (2) The surface whiteness of zinc deposits was decreased due to the change of the preferred orientation from (002) , (103) to (101) , (100) through increasing the organic additives and chlorine ion in the electrolyte. (3) The addition of Cu, Sn, Ni or Co in the chloride bath elevated the hardness of the zinc deposits but darkened the surface whiteness. (4) The optimum condition of the organic additives and the chlorine ion for increasing the hardness of zinc deposits and preventing dark surface ranges 0.3 m1/1 to 0.4 m1/1 and 6.5 mol/1 to 6.8mol/l respectively.

• Journal of Power System Engineering
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• v.5 no.1
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• pp.89-96
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• 2001

Decorative property of chromium deposition from oxalic acid bath containing chromium oxide and ammonium sulfate, has been examined over a wide range of bath compositions and plating conditions. The followings were determined as optimum bath composition, $CrO_3\;200{\sim}250g/{\ell},\;H_2C_2O_4{\cdot}2H_2O\;500{\sim}700g/{\ell},\;(NH_4){_2}SO_4\;40{\sim}120g/{\ell}$, and operation conditions; pH $2.0{\sim}2.5$, current density of $15{\sim}250Adm^2 $ at the bath temperatures of $30{\sim}80^{\circ}C$. Bright chromium deposits were obtained over a wide range of ammonium sulfate concentration, bath temperature, and current density. The current efficiency decreased with increasing current density and bath pH, and increased with Increasing bath temperature. The highest current efficiency was obtained in the bath containing $80g/{\ell}$ of ammonium sulfate. Bright chromium deposits were not obtained at conditions of all the highest current efficiencies.

• Journal of Power System Engineering
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• v.8 no.3
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• pp.36-43
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• 2004

The effect of bath composition, plating condition and plating rate on the magnetic property of electroless Co-Cu-P deposits were investigated. With increasing $CuCl_2$ concentration in the bath, plating rate increased, while the Br value of deposit decreased sharply. Deposited surface were inferiority by the increase pH above 10.5, bath temperature higher than $80^{\circ}C$. Plating reaction had been ceased by the increase of pH above 11, bath temperature higher than $90^{\circ}C$ and under $40^{\circ}C$. The Br value of deposit was uniform with various concentration of complexing agent(sodium citrate) in the bath. The Br value of deposit was almost equal to that found by the addition of stabilizer (thiourea) and accelerator(NaF). The Br value of deposit was uniform in plating time(20min) and heat treatment temperature(below $200^{\circ}C$), and were confirmed to have adequate bath stability for practical use.

• Journal of Power System Engineering
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• v.10 no.3
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• pp.58-66
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• 2006

The effect of bath composition, plating condition and plating rate on the magnetic properties of electroless Ni-Cu-P deposits were investigated. With increasing $CuSO_4$ concentration in the bath, plating rate increased, while the Br value of deposits decreased Sharply. Plating rate increased up to 34% with the addition of 200ppm of NaF and 0.8ppm of Thiourea to the bath. Plating reaction had been ceased by the increase of pH above 11.3, bath temperature higher than $90^{\circ}C$ and under $70^{\circ}C$. The Br value of deposit was uniform with various concentration of complexing agent (Sodium citrate, Ethylenediamine) in the bath. The Br value of deposit was almost equal to that found by the addition of stabilizer(Thiourea) and accelerator(NaF). The Br value of deposit was uniform in plating time(120 min) and heat treatment temperature(below $200^{\circ}C$), and were confirmed to have adequate bath stability for practical use.

• Journal of Korean Society of Rural Planning
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• v.3 no.1
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• pp.105-113
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• 1997

The actual situation of the rural house already improved since 1970's by standard plan of rural house was surveyed, to find out residential problems and farmers'intention to the improvement, and to make some space composition. The floor space of a living room and sanitary and bath facilities be required of larger dimensions than present. Facilities of sanitary and bath should be stayed indoors. The using-much-room is necessary to washing · and dressing after farm working. The space composition of rural house be variously developed on the basis of farmers'characteristies.

• Journal of the Korean institute of surface engineering
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• v.19 no.1
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• pp.3-12
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• 1986

Influences of pH, temperature, and composition of bath on the deposition rate and the magnetic properties were studied for two kinds of electroless Co-P plating bath. The results obtained are as follows. Ammonia alkaline citrate bath was more stable than ammonia alkaline tartrate bath, and the film deposited from citrate bath gave a higher squareness. The magnetic properties of the film obtained from citrate bath greatly depended upon pH. Under the optimum conditions, the film deposited from citrate bath had coercive force of 330 Oe and squareness of 0.67. However the films deposited from tartrate bath had coercive force of 300 Oe and squareness of 0.58.

• Journal of Power System Engineering
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• v.5 no.2
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• pp.71-78
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• 2001

Using sodium hypophosphite as reducing agent, bath composition and plating condition of electroless copper plating on plating rate have been studied. The followings were determined as optimum, bath composition; $CuSO_4\;0.025M,\;NiSO_4\;0.002M,\;NaH_2PO_2\;0.4M$, sodium citrate 0.06M, $H_3BO_3$ 0.6M, thiourea or 2-MBT $0.2mg/{\ell}$, and operation conditions; pH $9{\sim}10$ at bath temperature rage of $60{\sim}70^{\circ}C$. A small amount of nickel ion($Ni^{2+}/Cu^{2+}$=0.002/0.025) to the hypophosphite reduced solution promotes autocatalysis and continuous plating. An additive such as thiourea or 2-MBT of a small amount($0.2mg/{\ell}$) can be used to stabilize the solution without changing plating rate much. The attivation energy between $20^{\circ}C\;and\;70^{\circ}C$ were calculated to be 11.3kcal/mol for deposition weight. Plating reaction had been ceased by the adjustment of pH above 13, temperature higher than $90^{\circ}C\;and\;under\;20^{\circ}C$. Deposited surface became worse in the case of increment of bath temperature above $80^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.33 no.2
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• pp.126-134
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• 2000

This study investigated the bath compositions and plating conditions and crystal structure used for achieving nickel-thallium-phosphorus deposits by means electroless plating. The electroless nickel-thallium-phosphorus deposits were achieved with a bath using sodium hypophosphite as the reducing agent and sodium citrate as the complexing agent. The depositing rate was 10.5mg.$cm^{2-1}$ .$hr^{-1 }$ from the optimistic bath composition, 0.1M nickel sulfate, 0.005M thallium sulfate, 0.2M sodium hypophosphite, and 0.05M sodium citrat and the recommended plating conditions, pH 5.5 and $90^{\circ}C$. The composition of alloy deposits determined by X-ray analysis (EDS) that the Thallium was increased with major increasing concentration of complexing agent and thallium ion in bath solution, it decreased according to the increasing concentrations of reduction agent in the bath solution, Bit Phosphorus showed a contrary to the thallium. It was observed from X-ray diffraction analysis, Scanning Electron Microscopy and Transmission Electron Microscopy. The crystalline structure of deposits was amorphous at the first deposited state but it was changed $Ni-T1-Ni_{5}$ $P_2$ polycrystalline when subjected to 1 hour heat treatment of more than $350^{\circ}C$. TEM observation demonstrated that the microstructure was identical to the result of the XRD at as deposited but it became $Ni-Tl-Ni_{5}$ $P_2$ polycrystalline when heated. And grain size was 10-50nm.

• Journal of the Korean institute of surface engineering
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• v.12 no.2
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• pp.75-83
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• 1979

The Rates of formation and heats of activation for the intermatallic Compound Layers between Cold rolled sheet and molten aluminium &ath (adding small amounts of silicon) has been determined by Continous aluminizing method in the temperature range of 680$^{\circ}$ to 760$^{\circ}C$ and with immerssion time. The structure of the intermetallic Compound Layers was the shape of "Tongues" in pure Al-Bath and Al-Bath Containing 1% Si, But in Al-5% Si Bath was "Band" the Composition of the intermetallic Compound Layers were checked by microhardness measurements and X-Ray probe micro analyzer. FeAl intermetallic Compound layer was found to be uniform in pure Al-Bath and Al-5% Si Bath, But Fe Al intermetallic Compound Layer was shown in Al-1% Si Bath. The growth Rates of the intermetallic Compound Layers was most rapidly increased at Temperatures from 720$^{\circ}$ to 760$^{\circ}C$, at the immorsion time above 60 Second in pure Al-Bath, But in Al-1% Si Bath was solwly increased for the same conditions, and then in Al-5% Si Bath was hardly effected by these experimental condition. Heasts of activation of 29, 46 Kcal per mole which calculuted from Layer growth experiments were found in pure Al-Bath, Al-1% Si Bath respectively.