• 한국재료학회지
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• 제11권8호
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• pp.713-717
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• 2001

비정질 $Tb_{45.7}$ $Fe_{54.3-x}$ /$Co_{x}$ 및 $Tb_{50.2}$ /$_{Fe}$ 49.8-x/$Co_{x}$ (0$\leq$$x\leq$9.6) 합금박막의 자기적 특성 및 자기변형특성에 대하여 체계적으로 조사하였다. 박막제조는 Fe 타게트에 Tb, Co 소편으로 구성된 복합타겟 방식의 rf 마그네트론 스퍼터링법에 의해 제조하였다. XRD 조사에의 한 박막의 미세구조는 잘 발달된 비정질 구조를 나타내었다. $Tb_{45.7}$ $Fe_{54.3-x}$ $Co_{x}$ (x=2~4)에서 우수한 고유자기변형특성 및 저자기장자기변형특성을 얻었다. 즉, 100 Oe의 저자장에서 130ppm의 자기변형을 나타내었으며 고유자기변형 (인가 자기장, 5 kOe)은 330ppm에서 400ppm으로 증가하였다.

• Journal of Advanced Marine Engineering and Technology
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• 제29권1호
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• pp.98-106
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• 2005

The chemical conversion film formed on magnesium alloy was investigated by using the colloidal silica with some parameters such as solution pH. temperature, solution conditions, and treatment time. Moreover. the solutions consisted of colloidal silica titanium sulfate, and cobalt ions were used for the colloidal silica film to having a good corrosion resistance and adhesion properties. It was thought that the film at 298K was made with combination of Si-O. The quantity of film formed at high temperature such as 333K and 353K is smaller than dissolved quantity during chemical conversion treatment. Adding $CoSO_4$ to the colloidal silica solution enhanced the adhesion force between the silica film and magnesium substrate, The optimum conditions for the chemical conversion treatment solution were PH 2.90 s treatment, and 298K.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.40.1-40.1
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• 2007

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2004년도 하계학술연구발표회 논문개요집
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• pp.202-203
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• 2004

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.296.1-296.1
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• 2008

• 센서학회지
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• 제1권1호
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• pp.23-34
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• 1992

자기-저항 센서를 제작하기 위하여 Fe-Ni 합금과 Co-Ni 합금을 슬라이드 그라스와 Si wafer에 진공 증착하여 sensor element를 제작한 후 포화자속밀도($B_{s}$), 보자력($H_{c}$), 자기-저항 변화율 등을 조사하였다. 진공 증착된 Fe-Ni 합금 박막의 포화자속밀도는 0.65T이었으며 자화주파수 1 kHz에서 보자력은 0.379A/cm이었고 자냉처리 후 종방향 보자력은 0.370Acm(//), 횡방향 보자력은 0.390Acm(${\bot}$)로 변화되었다. 자기-저항 변화율은 박막의 산화로 인하여 매우 불안정하였다. 진공 증착된 Co-Ni 박막의 포화자속밀도는 0.66T이었으며 자냉처리 후의 종방향 보자력은 5.895Acm(//)이었고 횡방향 보자력은 5.898A/cm(${\bot}$)이었다. 한편 자기-저항 변화율(${\Delta}R/R$)은 $3.6{\sim}3.7%$로써 실온에서 매우 안정하였다. Fe-Ni 박막은 화학친화력이 강하여 자기-저항 센서 제조 공정에서 많은 문제점을 야기시키고 있으나, Co-Ni 박막은 화학친화력이 작고 자기-저항 효과가 뚜렷하여 고온용 자기-저항 소자 개발용 재료로 매우 적합할 것으로 사료된다.

• 한국재료학회지
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• 제7권2호
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• pp.136-139
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• 1997

증착법을 이용하여 $Sm(Co_{1-x}Fe_{x})$ 및 $Sm_{2}(Co_{1-x}Fe_{x})_{17}$(X=0, 0.3,0.5,0.7)박막을 제작하여 조성변화 및 열처리 온도 변화에 따른 자기적 성질의 변화에 대해 검토 하였다. Fe의 양이 증가 할 수록 포화자화 값은 증가 하지만 각형비는 감소하였고 보자력도 약간 감소하는 경향을 보였다. $Sm(Co_{0.5}Fe_{0.5})_{5}$ 조성박막의 경우, $800^{\circ}C$, 20분 열처리에 의해 약 6.1MGOe의 $(BH)_{max}$을 보였다. 본 박막자석의 자기적 성질의 증대를 위해서는 시료제작 방법의 개선이 필요하다고 사료 된다.

• Journal of Electrochemical Science and Technology
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• 제9권3호
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• pp.202-211
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• 2018

In this work, Fe-Pd alloy films have been electrodeposited on different substrates using an electrolyte containing $[Pd(NH_3)_4]^{2+}$ (0.02 M) and $[Fe-Citrate]^{2+}$ (0.2 M). The influences of substrate and overpotential on chemical composition, nucleation and growth kinetics as well as the electrodeposited films morphology have been investigated using energy dispersive X-ray spectroscopy (EDS), current-time transients, scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD) patterns. In all substrates - brass, copper and sputtered fluorine doped tin oxide on glass (FTO/glass) - Fe content of the electrodeposited alloys increases by increasing the overpotential. Also the cathodic current efficiency is low due to high rate of $H_2$ co-reduction. Regarding the chronoamperometry current-time transients, it has been demonstrated that the nucleation mechanism is instantaneous with a typical three dimensional (3D) diffusion-controlled growth in the case of brass and copper substrates; while for FTO, the growth mode changes to 3D progressive. At a constant overpotential, the calculated number of active nucleation sites for metallic substrates is much higher than that of FTO/glass; however by increasing the overpotential, the number of active nucleation sites increases. The SEM micrographs as well as the XRD patterns reveal the formation of Fe-Pd alloy thin films with nanostructure arrangement and ultra-fine grains.

• Corrosion Science and Technology
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• 제12권6호
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• pp.295-303
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• 2013

Silane surface treatments have been developed as an alternative for toxic and carcinogenic chromate-based treatments for years. It is consistently observed that ultra-thin films offer excellent corrosion protection as well as paint adhesion to metals. The silane performance is comparable to, or in some cases better than, that of chromate layers. Based on the tetra-ethylorthosilicate(TEOS) and methlyl trieethoxysilane(MTES), inorganic sol was synthesized and formed hybrid networks with $SiO_2$ nano particle and polypropylene glycol(PPG) on Zn alloyed steel surface. According to SST results, addition of 10nm and 50nm $SiO_2$ nanoparticle in synthesized solution improved anti-corrosion property by its shear stress relaxation effect during curing process. Also, SST results were shown that anti-corrosive property was affected by the amounts of organic compounds.

• Journal of Magnetics
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• 제18권1호
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• pp.5-8
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• 2013

The perpendicular magnetic anisotropy of sputtered CoFeB thin films covered by MgO was investigated by vibrating sample magnetometry. Three different $Co_xFe_{80-x}B_{20}$ alloys were studied. Under out-of plane magnetic field, the saturation field was found to increase with increasing the Co content. The magnetization and interface anisotropy energy were obtained for all samples. Both showed a marked dependence on the MgO overlayer thickness. In addition, their variations were found to be non-monotonous as a function of the Co concentration.