• 제목/요약/키워드: High temperature annealing

검색결과 906건 처리시간 0.03초

Fe-Si-Cr 분말합금의 열처리 효과 (Effects of Annealing of Gas-atomized Fe-Si-Cr Powder)

  • 장평우
    • 한국자기학회지
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    • 제26권1호
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    • pp.7-12
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    • 2016
  • 전기비저항이 높아 1 MHz 이상 고주파용 코어재료로 적합한 Fe-9%Si-2%Cr 합금분말의 열처리 온도에 따른 투자율 거동과 규칙-비규칙 전이에 대해 연구하였다. 분무과정에서 B2 규칙상의 생성이 억제되지 않았으며, $550^{\circ}C$ 이상에서 열처리 했을 경우 $DO_3$ 상의 회절선을 검출할 수 있었다. 열처리 온도가 증가할수록 격자상수와 보자력은 감소하였으나 $450^{\circ}C$에서 보자력의 갑작스런 큰 증가가 있었다. $150^{\circ}C$의 비교적 낮은 열처리 온도에서 가장 높은 투자율을 나타내었고, 이후 열처리 온도가 증가할수록 투자율은 감소하였다. 이상의 거동은 $DO_3$ 규칙상의 생성과 이에 따른 비저항의 변화로 설명할 수 있었다.

Annelaing Effects on the Dielectric Properties of the (Ba, Sr) $TiO_3$Films on $RuO_2$Bottom Electrodes

  • Park, Young-Chul;Lee, Joon;Lee, Byung-Soo
    • The Korean Journal of Ceramics
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    • 제3권4호
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    • pp.274-278
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    • 1997
  • (Ba, Sr) TiO$_3$(BST) thin films were prepared on RuO$_2$/Si substrates by rf magnetron sputtering and annealing was followed at temperatures ranging from 550 to 80$0^{\circ}C$ in $N_2$or $O_2$atmosphere. The effects of annealing conditions on the properties of BST film deposited on RuO$_2$bottom electrodes were investigated. It was found that the crystallinity. surface roughness, and grain size of BST films vary with the annealing temperature but they are not dependent upon the annealing atmosphere. The flat region in the current-voltage (I-V) curves of BST capacitors shortened with increasing annealing temperature under both atmospheres. This is believed to be due to the lowering of potential barrier caused by unstable interface and the increase of charge The shortening of the flat region by $O_2$annealing was more severe than that by $N_2$-annealing. As a result, there was no flat region when the films were annealed at 700 and 80$0^{\circ}C$ in $O_2$atmosphere. The dielectric properties of BST films were improved by annealing in either atmosphere. however, a degradation with frequency was observed when the films were annealed at relatively high temperature under $O_2$atmosphere.

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FDM 3D프린팅 어닐링 조건에 따른 내부응력 완화에 관한 연구 (Investigation of the Internal Stress Relaxation in FDM 3D Printing : Annealing Conditions)

  • 이선곤;김용래;김수현;김주형
    • 한국기계가공학회지
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    • 제17권4호
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    • pp.130-136
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    • 2018
  • In this paper, the effects of different 3D printing parameters including laminated angle and annealing temperature, were observed for their effects on tensile testing. In 3D printing, a filament is heated quickly, extruded, and then cooled rapidly. Because plastic is a poor heat conductor, it heats and cools unevenly causing the rapid heating and cooling to create internal stress within the printed part. Therefore, internal stress can be removed using annealing and to increase tensile strength and strain. During air cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 46% while the tensile stress tended to increase by 7.4%. During oven cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 34% while the tensile stress tended to increase by 22.2%. In this study, we found "3D printing with annealing" eliminates internal stress and increases the strength and stiffness of a printed piece. On the microstructural level, annealing reforms the crystalline structures to even out the areas of high and low stress, which created fewer weak areas. These results are very useful for making 3D printed products with a mechanical strength that is suitable for applications.

상용 AZ31B Mg합금 판재의 어닐링에 따른 집합조직 변화 및 결정립 이상 성장 (Effects of Annealing on the Texture Development and Abnormal Grain Growth in a Commercial AZ31B Mg Alloy Sheet)

  • 양권승;윤성식;장우양;강조원
    • 열처리공학회지
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    • 제21권6호
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    • pp.293-299
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    • 2008
  • In order to provide with fundamental data of the wrought Mg alloy for press forging, the effect of annealing temperature on the microstructure, texture development and tensile properties is studied in a commercial AZ31B Mg alloy sheet. Basal texture i.e. $(0001){\pm}5^{\circ}$[21$\bar{3}$0] is developed in a commercial AZ31B Mg sheet, and the texture is not changed considerably by annealing over $400^{\circ}C{\times}30min$, while (10$\bar{3}$0) component with high intensity can be observed due to abnormal grain growth. When the sheet is tensile-deformed with RD, $45^{\circ}$ and TD directions at room temperature, fracture strains are given by 25.8, 21.4 and 11.9% in the order of RD, $45^{\circ}$ and TD directions, respectively. With increasing annealing temperature up to $450^{\circ}C{\times}30min$, little change in mean grain size can be revealed by annealing below $300^{\circ}C{\times}30min$ but an abnormal grain growth, where some grains become significantly coarser than the rest, occurs by annealing above $400^{\circ}C{\times}30min$. The maximum tensile strain of around 25% is obtained by annealing below $300^{\circ}C{\times}30min$, but it is abruptly decreased to 16% by annealing above $400^{\circ}C{\times}30min$ owing to intergranular fracture of abnormal grown grains.

$Co_{67}Fe_{4.5}Nb_{2}Si_{10}B_{15}$ 비정질합금의 자성에 미치는 2단 어닐링의 효과 (Effect of Two-step Annealing on the Magnetic Properties of $Co_{67}Fe_{4.5}Nb_{2}Si_{10}B_{15}$ Amorphous Alloy)

  • 김희중;김광윤;강일구;이명복;이종현
    • 한국자기학회지
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    • 제2권2호
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    • pp.91-98
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    • 1992
  • $Co_{67}Fe_{4.5}Nb_{2}Si_{10}B_{15}$ 비정질합금리본에서 2단 어닐링이 자기특성에 미치는 영향을 조사 하였다. 고온인 $480^{\circ}C$ 이상에서 20분간 1단 어닐링한 리본을 저온인 $310^{\circ}C$에서 2시간 동안 2단으로 진공어닐링한 결과 보자력과 각형비는 1단 어닐링한 경우와 거의 비슷한 값들을 나타내었으나, 직류 및 교류투자율은 1단 어닐링에 비해 현저히 높아졌다. 2단 어닐링시 직류 및 1 kHz에서의 교류투자율의 최대치는 각각 약 290,000과 41,000으로서 1단 어닐링에 비해 30% 이상 증가하였다. 어닐링온도에 따른 자성의 변화는 3단계로 나누어 내부응력, 자구크기, cluster 및 결정상의 변화를 주요 요인으로 하여 고찰하였다.

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DLC 박막을 이용한 액정 배향 효과 (Liquid Crystal Alignment Effects using a DLC Thin Film)

  • 조용민;황정연;서대식;노순준;이대규;백홍구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.346-349
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    • 2001
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about $4^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $220^{\circ}C$. Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

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DLC 박막을 이용한 액정 배향 효과 (Liquid Crystal Alignment Effects using a DLC Thin Film)

  • 조용민;황정연;서대식;노순준;이대규;백흥구
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.346-349
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    • 2001
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of diamond like carbon (DLC) thin film. A high pretilt angle of about 4$^{\circ}$ was measured by ion beam(IB) exposure on the DLC thin film surface. A good LC alignment was observed by the IB alignment method on the DLC thin film surface at annealing temperature of 200$^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of 220$^{\circ}C$ . Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment can be achieved by the IB alignment method on the DLC thin film surface.

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Diamond-like Carbon 박막을 이용한 액정 배향 효과 (Liquid Crystal Alignment Effects using a Diamond-like Carbon Thin Film)

  • 황정연;조용민;서대식;노순준;이대규
    • 한국전기전자재료학회논문지
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    • 제15권5호
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    • pp.419-422
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    • 2002
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of a diamond like carbon (DLC) thin film. A high pretilt angle of about $3.5^{\circ}$ by ion beam(IB) exposure on the DLC thin film surface was measured. A good LC alignment by the IB alignment method on the DLC thin film surface was observed at annealing temperature of $200^{\circ}C$, and the alignment defect of the NLC was observed above annealing temperature of $220^{\circ}C$. Consequently, the high NLC pretilt angle and the good thermal stability of LC alignment by the IB alignment method on the DLC thin film surface can be achieved.

6H-SiC MOSFET과 디지털 IC 제작 (Fabrication of 6H-SiC MOSFET and Digital IC)

  • 김영석;오충완;최재승;송지헌;이장희;이형규;박근형
    • 한국전기전자재료학회논문지
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    • 제16권7호
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    • pp.584-592
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    • 2003
  • 6H-SiC MOSFETs and digital ICs have been fabricated and characterized. PMOS devices are fabricated on an n-type epilayer while the NMOS devices are fabricated on implanted p-wells. NMOS and PMOS devices use a thermally grown gate oxide. SiC MOSFETs are fabricated using different impurity activation methods such as high temperature and newly proposed laser annealing methods. Several digital circuits, such as resistive road NMOS inverters, CMOS inverters, resistive road NMOS NANDs and NORs are fabricated and characterized.

급속열처리에 의한 TiN/$TiSi_2$ 이중구조막을 이용한 submicron contact에서의 전기적 특성 (The Electrical Roperties of TiN/$TiSi_2$ Bilayer Formed by Rapid Thermal Anneal at Submicron Contact)

  • 이철진;성만영;성영권
    • 전자공학회논문지A
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    • 제31A권9호
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    • pp.78-88
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    • 1994
  • The electrical properties of TiM/TiSi$_{2}$ bilayer formed by rapid thermal anneal in NH$_{3}$ ambient after the Ti film is deposited on silicon cubstrate are investigated. N$^{+}$ contact resistance slightly increases with increasing annealing temperature with P$^{+}$ contact resistance decreases. The contact resistance of N$^{+}$ contance was less than 24[.OMEGA.] but P$^{+}$ thatn that of N$^{+}$ contact but the leakage current indicates degradation of the contact at high annealing temperature for both N$^{+}$ and contacts. The leakage current of N$^{+}$ Junction was less than 0.06[fA/${\mu}m^{2}$] but P$^{+}$ contact was 0.11-0.15[fA/${\mu}m^{2}$]. The junction breakdown voltage for N$^{+}$ junction remains contant with increasing annealing temperature while P$^{+}$ junction slightly decreases. The Electrical properties of a two step annealing are better than that of one step annealing. The Tin/TiSi$_{2}$ bilayer formed by RTA in NH$_{3}$ ambient reveals good electrical properties to be applicable at ULSI contact.

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