• Title/Summary/Keyword: solution annealing

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Effect of Austenitizing Ratio on the Delta Ferrite Volume Fraction and Corrosion Resistance of Shell Mold Cast SSC13 Elbow Fitting (셀 몰드 주조한 SSC13 엘보우 피팅 주강의 고용화율에 따른 델타 페라이트 분율 변화와 내부식특성)

  • Kim, Kuk-Jin;Lim, Su-Gun;Ju, Heong-kyu;Pak, Sung-Joon
    • Journal of Korea Foundry Society
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    • v.35 no.5
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    • pp.109-113
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    • 2015
  • In this study, the measurement of FN (ferrite volume fraction) and the solution annealing ratio at a temperature of $1130^{\circ}C$ were determined with 15A elbow fittings of shell cast SSC13, and the corrosion resistance with and without austenitizing solution annealing were investigated in comparison with AISI304. The delta ferrite phase was observed in the material due to the slow cooling effect of the shell mold casting. However, the delta ferrite phase decreased gradually with the solution annealing at a temperature of $1130^{\circ}C$. The hardness generally decreased with a heat treatment; however, its corrosion resistance was improved with the heat treatment. In addition, when a passivation treatment was applied, its corrosion ratio showed the lowest value. The pattern of general corrosion decreased due to the decrease in the delta ferrite phase with the solution annealing treatment. Consequently, it is suggested that the corrosion resistance of SSC13 elbow fittings can be improved by increasing the ratio of any solution annealing treatment used and by decreasing the ferrite phase. The relationship between the ratio of solution annealing and delta ferrite is expressed as follows: SA (solution annealing ratio,%) = 98 - FN (ferrite volume fraction, %).

MODIFIED SIMULATED ANNEALING ALGORITHM FOR OPTIMIZING LINEAR SCHEDULING PROJECTS WITH MULTIPLE RESOURCE CONSTRAINTS

  • Po-Han Chen;Seyed Mohsen Shahandashti
    • International conference on construction engineering and project management
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    • 2007.03a
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    • pp.777-786
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    • 2007
  • This paper presents a modified simulated annealing algorithm to optimize linear scheduling projects with multiple resource constraints and its effectiveness is verified with a proposed problem. A two-stage solution-finding procedure is used to model the problem. Then the simulated annealing and the modified simulated annealing are compared in the same condition. The comparison results and the reasons of improvement by the modified simulated annealing are presented at the end.

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A Study of Annealing Heat-treatment for Ti(Grade 2) by Electrochemical Methods (전기화학적 방법을 이용한 Ti(Grade 2)재의 최적 어닐링 열처리에 대한 연구)

  • 백신영
    • Journal of Advanced Marine Engineering and Technology
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    • v.26 no.1
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    • pp.90-98
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    • 2002
  • In this paper, the annealing heat treatments for the best corrosion resistant of Ti(Grade 2) were studied in a 3.5% NaCl solution by electrochemical methods. The annealing heat treatments were accomplished at 650, 700 and $750^{\circ}C$ with different time of 30min., 1hour and 2 hours in a vacuum condition. The obtained results are: 1) in the case of solution heat treated $930^{\circ}C$ for 2 hours in a vacuum and air, the corrosion potentials were -348.7 and -567. 1mV, and current densities 2.32 and $22.62\mu\textrm{A}$, respectively, 2) as increase both annealing heat treatment temperature 650, 700, $750^{\circ}C$ and time 30min., 1 hour, 2 hours, the corrosion potential were decreased, whereas corrosion current density increased, 3) in the case of cyclic polarization, the measured charges were increased as increasing solution heat treatment temperature and time, 4) on the bases of corrosion potential, current density and charge, the best annealing temperature and time were measured as $700^{\circ}C$ and 30min. for Ti(Grade 2) material.

Enhanced Crystallization of Amorphous Si Using viscous Ni Solution and Microwave Annealing

  • Ahn, Jin-Hyung;Eom, Ji-Hye;Ahn, Byung-Tae
    • Journal of Information Display
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    • v.2 no.2
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    • pp.7-12
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    • 2001
  • A viscous Ni solution was coated over amorphous Si thin film for evenly spread of Ni metal source. The Ni s. prepared by dissolving $NiCl_2$ into IN HCI and mixing with propylene glycol. $NiCl_2$ and Ni were deposited on the amorphous film after oven dry and they enabled to obtain a uniform crystallization. The crystallization using the viscous Ni solution was a Ni-silicide mediated process, the same process used with Ni metal layer. The crystallization temperature was lowered to $480^{\circ}C$ by the synergy effect of silicide-mediated crystallization and microwave-induced crystallization. Lateral crystallization was also enhanced such that the velocity of lateral crystallization by microwave annealing became faster than by furnace annealing.

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Stress Corrosion Cracking Behavior of Cold Worked 316L Stainless Steel in Chloride Environment

  • Pak, Sung Joon;Ju, Heongkyu
    • Journal of Korea Foundry Society
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    • v.40 no.5
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    • pp.129-133
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    • 2020
  • The outcomes of solution annealing and stress corrosion cracking in cold-worked 316L austenitic stainless steel have been studied using x-ray diffraction (XRD) and the slow strain rate test (SSRT) technique. The good compatibility with a high-temperature water environment allows 316L austenitic stainless steel to be widely adopted as an internal structural material in light water reactors. However, stress corrosion cracking (SCC) has recently been highlighted in the stainless steels used in commercial pressurized water reactor (PWR) plants. In this paper, SCC and inter granular cracking (IGC) are discussed on the basis of solution annealing in a chloride environment. It was found that the martensitic contents of cold-worked 316L stainless steel decreased as the solution annealing time was increased at a high temperature. Moreover, mode of SCC was closely related to use of a chloride environment. The results here provide evidence of the vital role of a chloride environment during the SCC of cold-worked 316L.

Performance of Solution Processed Zn-Sn-O Thin-film Transistors Depending on Annealing Conditions

  • Han, Sangmin;Lee, Sang Yeol;Choi, Jun Young
    • Transactions on Electrical and Electronic Materials
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    • v.16 no.2
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    • pp.62-64
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    • 2015
  • We have investigated zinc tin oxide (ZTO) thin films under various silicon ratios. ZTO TFTs were fabricated by solution processing with the bottom gate structure. Furthermore, annealing process was performed at different temperatures in various annealing conditions, such as air, vacuum and wet ambient. Completed fabrication of ZTO TFT, and the performance of TFT has been compared depending on the annealing conditions by measuring the transfer curve. In addition, structure in ZTO thin films has been investigated by X-ray diffraction spectroscopy (XRD) and Scanning electron microscope (SEM). It is confirmed that the electrical performance of ZTO TFTs are improved by adopting optimized annealing conditions. Optimized annealing condition has been found for obtaining high mobility.

The Effects of Process Parameters on Properties of CdS Thin Films Prepared by Solution Growth Method

  • Kim, Soo-Gil;Lee, Yong-Eui;Kim, Sang-Deok;Kim, Hyeong-Joon;Jinsoo Song;Yoon, Kyung-Hoon;Park, Byung-Ho
    • The Korean Journal of Ceramics
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    • v.3 no.1
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    • pp.57-61
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    • 1997
  • The effects of pH of solution on structural, electrical, and optical properties of CdS thin films prepared by solution growth method were investigated. With increasing pH of the solution, both crystallinity and transmittance of CdS thin film were deteriorated due to impurities and CdS particles, which were produced by homogeneous nucleation and adsorbed on the surface of CdS thin films. The films were strongly adherent to substrates and has low resistivity of 10~$10^2{\omega}cm$ regrardless of deposition conditions. After annealing at 30$0^{\circ}C$ in Ar atmosphere, the resistivity decreased due to desorption of impurity ions as well as the formation of S vacancies, but after annealing above 35$0^{\circ}C$ it increased by an agglomeration of S vacancies. After annealing in air atmosphere, the film resistivity increased because of the formation of oxide particle in grain boundaries.

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Study on Solution Processed Indium Zinc Oxide TFTs Using by Femtosecond Laser Annealing Technology (펨토초 레이저 어닐링 기술을 이용한 용액 공정 기반의 비정질 인듐 징크 산화물 트랜지스터에 관한 연구)

  • Kim, Han-Sang;Kim, Sung-Jin
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.1
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    • pp.50-54
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    • 2018
  • In this study, a femtosecond laser pre-annealing technology based on indium zinc oxide (IZO) thin-film transistors (TFTs) was investigated. We demonstrated a stable pre-annealing process to analyze the change in the surface structures of thin-films, and we improved the electrical performance. Furthermore, static and dynamic electrical characteristics of IZO TFTs with n-channel inverters were observed. To investigate the static and dynamic responses of our solution-processed IZO TFTs, simple resistor-load-type inverters were fabricated by connecting a $1-M{\Omega}$ resistor. The femtosecond laser pre-annealing process based on IZO TFTs showed good performance: a field-effect mobility of $3.75cm_2/Vs$, an $I_{on}/I_{off}$ ratio of $1.8{\times}10^5$, a threshold voltage of 1.13 V, and a subthreshold swing of 1.21 V/dec. Our IZO-TFT-based N-MOS inverter performed well at operating voltage, and therefore, is a good candidate for advanced logic circuits and display backplane.

Effect of Annealing Conditions on Microstructure and Damping Capacity in AZ61 Magnesium Alloy (열처리조건에 따른 AZ61 마그네슘 합금의 미세조직과 감쇠능에 미치는 영향)

  • Ahn, Jae-Hyeon;Kim, Kwon-Hoo
    • Journal of the Korean Society for Heat Treatment
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    • v.31 no.2
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    • pp.56-62
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    • 2018
  • Many researchers have studied on the precipitation control after solution treatment to improve the damping capacity without decreasing the strength. However, studies on the damping capacity and microstructure changes after deformation in the solid solution strengthening alloys were inadequate, such as the Al-Zn series magnesium alloys. Therefore, in order to investigate the effect of annealing condition on microstructure change and damping a capacity of AZ61 magnesium alloy. In this study, it was confirmed that the microstructure changes affect the damping capacity and hardness when annealed AZ61 alloy. AZ61 magnesium alloy was rolled at $400^{\circ}C$ with rolling reduction of 30%. These specimens were annealed at $350^{\circ}C$ to $450^{\circ}C$ for 30-180 minutes. After annealing, microstructure was observed by using optical microscopy, and damping capacity was measured by using internal friction measurement machine. Hardness was measured by Vickers hardness tester under a condition of 0.3 N. In this study, static recrystallization was observed regardless of the annealing conditions. In addition, uniform equiaxed grain structure was developed by annealing treatment. Hardness is decreased with increasing grain size. This is associated with Hall-Petch equation and static recrystallization. In case of damping capacity, bigger grain size show the larger damping capacity.

Solution Processable Ionic p-i-n OLEDs (습식 이온 도핑 p-i-n 구조 유기 발광 소자)

  • Han, Mi-Young;Oh, Seung-Seok;Park, Byoung-Choo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.11
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    • pp.974-979
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    • 2009
  • We studied solution-processed single-layered phosphorescent organic light-emitting diodes (PHOLEDs), doped with ionic salt and treated with simultaneous electrical and thermal annealing. Because the simultaneous annealing causes the accumulation of salt ions at the electrode surfaces, the energy levels of the organic molecules are bent by the electric fields due to the adsorbed ions, i.e., the simultaneous annealing can induce the proper formation of an ionic p-i-n structure. As a result, an ionic p-i-n PHOLED with a peak luminescence of over ${\sim}35,000\;cd/m^2$ and efficiency of 27 cd/A was achieved through increased and balanced carrier-injections.