• 제목/요약/키워드: 집합조직 발달

검색결과 46건 처리시간 0.028초

Al-5%Mg 합금 판재의 집합조직 발달에 미치는 냉간 압하율의 영향 (The effect of cold rolling reduction ratio on the texture evolution in Al-5% Mg alloy)

  • 최재권;김형욱;강석봉;최시훈
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 추계학술대회 논문집
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    • pp.102-105
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    • 2008
  • To investigate the evolution of deformation texture during cold rolling deformation, cold rolling process on a commercial Al-5% Mg sheet was carried out at different rolling reduction ratio. The evolution of annealing texture in cold-rolled Al-5% Mg sheet was also investigated. The evolution of recrystallization texture during annealing process strongly depends on the rolling reduction ratio before heat treatment. Visco-plastic self-consistent (VPSC) polycrystal model was used to predict r-value anisotropy of the cold-rolled and annealed Al-5% Mg sheets. The change of volume fraction for the major texture components was also analyzed.

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AA1050 판재의 비대칭 압연 시 변형률 상태와 집합조직 발달에 미치는 압연변형 형상의 영향 (Effect of Roll Gap Geometry on the Evolution of Strain States and Textures during Asymmetrical Rolling in AA1050)

  • 강형구;나정준;허무영
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.219-221
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    • 2006
  • Asymmetrical rolling was performed by rolling AA 1050 sheets with different velocities of upper and lower rolls. In order to study the effect of roll gap geometry on the evolution of strain states and textures during asymmetrical rolling, the reduction per rolling pass was varied. After asymmetrical rolling, the outer thickness layers depicted shear textures and the center thickness layers displayed a random texture. With decreasing reduction per an asymmetrical rolling pass, the thickness layers depicting shear textures increases. The strain states associated with asymmetrical rolling were investigated by simulations with the finite element method (FEM).

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냉간가공과 열처리한 Ni 테이프에서의 집합조직 발달 (Texture development in cold-roiled and heat-treated Ni tapes)

  • 이동욱;지봉기;임준형;주진호;정충환;박순동;전병혁;홍계원;김찬중
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.535-538
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    • 2002
  • Cube-textured Ni substrates for YBCO coated conductors were fabricated by cold-rolling and annealing of Ni powder compacts. To establish the optimum sintering temperature, tensile test was performed for the Ni rod sintered at various temperatures. The Ni rods prepared at above 100$0^{\circ}C$ showed good mechanical properties due to the complete densification of the Ni rods. The Ni rods were rolled to final thickness of 100 ${\mu}{\textrm}{m}$ and then annealed at 100$0^{\circ}C$ for various annealing time for texture development. The texture analysis made by 2 $\theta$ scan and pole-figure showed that the cube texture was developed in a short time of a few munitues. The FWHM of in-plane and out of plane texture of the prepared Ni tapes was 8-10$^{\circ}$. The AEM surface roughness of the Ni tapes was as smooth as 3 nm.

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비대칭 압연한 IF 강 판의 Goss 집합조직 발달 (Goss Texture Development of Asymmetrically Rolled IF Steel Sheet)

  • 김인수;남수권;김광희;이동녕
    • 소성∙가공
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    • 제26권3호
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    • pp.150-155
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    • 2017
  • To obtain the Goss texture, {110}<001>, IF steel sheets were asymmetrically rolled by 50-89% reduction in the thickness at room temperature and subsequently annealed at 200, 900, and $1200^{\circ}C$ in a box furnace under air atmosphere. The asymmetrically rolled specimens and annealed specimens show well-developed Goss texture, {110}<001>. After the IF steel sheets were asymmetrically rolled at room temperature and subsequently annealed at $900^{\circ}C$ for 1 h in a box furnace under air atmosphere, the intensity of the Goss texture, {110}<001> was high in the IF steel sheets.

비대칭 압연한 마그네슘 합금판재의 집합조직 발달 (Texture Evolution of Asymmetrically Rolled Mg Alloy Sheets)

  • 정효태;이규동;이수연;하태권;최병학
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 추계학술대회 논문집
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    • pp.64-66
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    • 2007
  • Asymmetric rolling, where circumferential velocities of the upper and lower rolls differ, can be one method to change texture of magnesium alloy sheet by introducing shear deformation throughout the thickness of a sheet. In this study, the texture, microstructure and mechanical properties of AZ31 Mg sheets has been investigated during the symmetrical rolling procedure and the asymmetric rolling procedures of different roll speeds with different roll diameters. Texture of Mg alloy sheets were evaluated by using X-ray diffraction and ODFs were calculated using ADC method. The major texture of rolled specimens can be expressed by ND//(0001) fiber texture. The major fiber texture changed according to the rolling processes and such a slight difference of texture changes the formability of sheets. The mechanical properties were enhanced during asymmetrical rolling.

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알루미늄 판재의 비대칭 냉간압연 시 집합조직 발달에 미치는 압연변수의 영향 (Effect of rolling parameters on the evolution of texture during asymmetrical cold rolling of aluminum sheets)

  • 강형구;한용희;허무영
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2007년도 추계학술대회 논문집
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    • pp.84-86
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    • 2007
  • Aluminum sheets were asymmetrically cold rolled without lubrication by using different roll velocities of upper and lower rolls in order to intensify the shear deformation. During asymmetrical cold rolling of aluminum sheets, a reduction per a rolling pass, initial sheet thickness, roll diameter, roll velocity ratio were varied to investigate the effect of rolling parameters. The formation of through thickness shear texture was related to the ratio of the contact length between the roll and sample($l_c$) to the sheet thickness(d). The strain states associated with asymmetrical rolling were investigated by the finite element method (FEM) simulation. FEM results indicated that the evolution of deformation texture in a thickness layer is strongly governed by integrated values of strain rates $\dot{\varepsilon}_{13}$ and $\dot{\varepsilon}_{11}$ along the streamline in the roll gap.

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디프드로잉에 의한 알루미늄합금판재의 집합조직 발달에 관한 연구 (Texture Evolution in Aluminum Alloy Sheets during Deep Drawing Process)

  • 최시훈;조재형;정관수;오규환
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 1998년도 제2회 박판성형심포지엄 논문집 박판성형기술의 현재와 미래
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    • pp.140-147
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    • 1998
  • The texture evolution by deep drawing was investigated and the lattice rotation rate was predicted using rate sensitive model with full constraints boundary conditions. The calculated textures show different behaviors with the amount of the flange deformation and initial crystal orientations. Among the crystal orientations located parallel to RD, the crystal orientations around the D component rotated toward the Cu component, the crystal orientations along the ${\alpha}$ fiber rotated toward the {110}<001> and {110}<111> components during deep drawing. In the case of the part parallel to 45$^{\circ}$ with respect to RD, the crystal orientations around the D component rotated about ND and the crystal orientations along the ${\alpha}$ fiber also rotated toward the (110)[23] and (110)[27] components about ND. In the part parallel to TD, the crystal orientations around the D component rotated toward the Rotated Cube and the crystal orientations along the ${\alpha}$ fiber rotated toward the {110}<113> component.

AA 5052 판재의 집합조직 발달과 결정립 크기에 미치는 다양한 냉간압연 공정의 영향 (Effect of various cold rolling process on the evolution of texture and recrystallized grain size in AA 5052 sheet)

  • 이준혁;나정준;허무영
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 춘계학술대회 논문집
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    • pp.408-410
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    • 2008
  • The evolution of texture and microstructure during recrystallization was tracked after different cold rolling of aluminum sheets. Texture of the sheet center were differentiated by different strain states due to prior deformation. The evolution of recrystallization texture was studied with the amount of shear applied during cold rolling. The final grain size after recrystallization annealing was varied due to the effective strain during deformation.

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페라이트계 스테인리스 강의 열간압연 시 표면 층의 집합조직 발달에 미치는 윤활의 영향 (Effect of Lubrication during Hot Rolling on the Evolution of Textures at the surface of 18%Cr Ferritic Stainless Steel Sheet)

  • 편영범;강형구;허무영
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2008년도 춘계학술대회 논문집
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    • pp.411-414
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    • 2008
  • In order to study the effect of lubrication during hot rolling, ferritic stainless steel (FSS) sheet were hot-rolled with and without application of lubrication. The effect of two hot rolling processes on the evolution of texture and microstructure after hot rolling, cold rolling and subsequent recrystallization annealing was studied by means of macro-texture analysis and microstructure observations. After hot rolling, the specimen rolled with lubrication showed rolling textures at the sheet surface, while the specimen rolled without lubrication displayed shear textures in the outer layers of the sheet. Hot rolling with lubrication was beneficial to the formation of strong recrystallization textures at sheet surface. However, hot rolling with lubrication led to the formation of orientation colonies in outer thickness layers of the recrystallized sheet.

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열간압연에 따른 AZ61 및 AZ80 마그네슘 합금의 미세조직 및 집합조직 발달에 대한 연구 (Development of Microstructure and Texture of AZ61 and AZ80 Magnesium Alloys by Hot Rolling)

  • 이지호;박노진
    • 열처리공학회지
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    • 제33권2호
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    • pp.49-56
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    • 2020
  • Magnesium alloy is a metal with high specific strength and light weight, and is attracting attention as a next generation metal for environmentally friendly automobiles and transportation equipment. However, magnesium alloys have a problem of degrading formability due to the basal texture developed during processing, and their application is limited. Although active researches on the control of textures have been conducted in order to minimize this problem, there is a lack of research on the formation of microstructures and textures according to elemental differences. In this study, AZ61 and AZ80 magnesium alloys were selected to investigate the effects of aluminum addition on the microstructure development of magnesium alloys. This research has proven that the increase of the rolling rate results in the decrease of the average grain size of the two alloys, the increase of the hardness, and the increase of the fraction of twins. As shown on this research below, the basal texture developed strongly as the rolling ratio increased. On the other hand, this research also has proven that the two alloys exhibited different texture strength and distribution tendencies, which could be due to the effects of aluminum addition on work hardening, grain size, and twin behavior.