• Title/Summary/Keyword: Quenching method

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A study on the Fracture of Coil Spring (파쇄기용 코일스프링의 파손에 관한 연구)

  • Jeong, Hyung-Sik;An, Se-Won;Lee, Jong-Hyung;Choi, Seong-Dae
    • Journal of the Korean Society of Industry Convergence
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    • v.9 no.1
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    • pp.51-59
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    • 2006
  • The study is diagnosis about fatigue failure phenomenon of heating coil spring (sup9) and heat treatment method that is used to crusher. Because more than 80~90% of damage announcement of breakdown of machine and construction is been caused in fatigue present state, fatigue failure became important leading person at design. Calculated design load is imposed repeatedly that fatigue breakdown is safe. Is phenomenon that change load is imposed in the construction continuously. Used coil spring applies heat 30minute by Quenching temperature $860^{\circ}C$ if see manufacturing process and temperature of gasoline of $50^{\circ}C$ keep after quench that know tempering a $460^{\circ}C$ 90minute a product be. If doto apply heat $950^{\circ}C$ material at rolling process historically before quenching, austenite formation clay pipe being done AGS(Austenite Grain Size) by 2.5~4 become. Apply heat quenching 30minute by $820^{\circ}C$ by improvement method and after quench that keep $50^{\circ}C$ in oil tempering if do $450^{\circ}C$, 90minute spring ideal formation sorbite formation of the river form and condition that satisfy most more than AGS 7 appeared. Also, we can secure authoritativeness through MT since shot peening processing.

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Quenching Effect in an Optical Fiber Type Small Size Dosimeter Irradiated with 290 MeV·u-1 Carbon Ions

  • Hirata, Yuho;Watanabe, Kenichi;Uritani, Akira;Yamazaki, Atsushi;Koba, Yusuke;Matsufuji, Naruhiro
    • Journal of Radiation Protection and Research
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    • v.41 no.3
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    • pp.222-228
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    • 2016
  • Background: We are developing a small size dosimeter for dose estimation in particle therapies. The developed dosimeter is an optical fiber based dosimeter mounting an radiation induced luminescence material, such as an OSL or a scintillator, at a tip. These materials generally suffer from the quenching effect under high LET particle irradiation. Materials and Methods: We fabricated two types of the small size dosimeters. They used an OSL material Eu:BaFBr and a BGO scintillator. Carbon ions were irradiated into the fabricated dosimeters at Heavy Ion Medical Accelerator in Chiba (HIMAC). The small size dosimeters were set behind the water equivalent acrylic phantom. Bragg peak was observed by changing the phantom thickness. An ion chamber was also placed near the small size dosimeters as a reference. Results and Discussion: Eu:BaFBr and BGO dosimeters showed a Bragg peak at the same thickness as the ion chamber. Under high LET particle irradiation, the response of the luminescence-based small size dosimeters deteriorated compared with that of the ion chamber due to the quenching effect. We confirmed the luminescence efficiency of Eu:BaFBr and BGO decrease with the LET. The reduction coefficient of luminescence efficiency was different between the BGO and the Eu:BaFBr. The LET can be determined from the luminescence ratio between Eu:BaFBr and BGO, and the dosimeter response can be corrected. Conclusion: We evaluated the LET dependence of the luminescence efficiency of the BGO and Eu:BaFBr as the quenching effect. We propose and discuss the correction of the quenching effect using the signal intensity ratio of the both materials. Although the correction precision is not sufficient, feasibility of the proposed correction method is proved through basic experiments.

The Effects on the Traditional Processing Operation of Hematite Medicinal Mineral through Heating and Quenching in Vinegar (전통적 초쉬법에 의한 적철석 약광물의 약재가공 효과)

  • Hwang, Jeong
    • Journal of the Korean earth science society
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    • v.29 no.7
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    • pp.523-530
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    • 2008
  • The phase changes and variations of elemental contents in hematite medicinal mineral were investigated by a traditional processing operation including heating and quenching in vinegar. Hematite was processed at $650^{\circ}C$ and $900^{\circ}C$ through at least 5 processing cycles. Metal extraction tests in water were carried out with the processed hematite. Heating and quenching in vinegar could not change the phase of hematite. The effect of this traditional method was not clear because there were no variational trends between extracted elements and the number of processing cycles at $650^{\circ}C$ and $900^{\circ}C$. However, the traditional processing operation of heating and quenching in vinegar was very effective to change the hematite mineral towards soft and easily crushing medicinal material.

A Study on the Heat Transfer of the High Temperature Metals in Quenching - The Latent Heat of Phase Transformation and Cooling Curves - (고온강재의 담금질 전열에 관한 연구)

  • 윤석훈
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.27 no.4
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    • pp.321-327
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    • 1991
  • Experiments of quenching were made with cylindrical specimens of carbon steel S45C of diameters from 12 to 30mm were performed. The specimens were heated by electric furnace and quenched by immersion method. In order to analyze the temperature profile(cooling curves) of carbon steel including the latent heat of phase transformation, nonlinear heat conduction problem was calculated by the numerical method of inverse heat conduction problem using the apparent heat capacity method. The difference between the calculated and the experimented cooling curves was caused by the latent heat of phase transformation, and the effects of the latent heat were especially manifest at the cooling curves of center of specimens. The temperature and the quantity of the latent heat of phase transformation depend on the cooling speed at A sub(1) transformation point, and the region for cooling speed to become zero was caused by the latent heat of phase transformation.

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The manufacturing process analysis and design of the forged turbine rotor by using the numerical analysis technique (수치해석 기법을 이용한 발전용 단조 로타의 제조 공정 분석 및 공정 설계)

  • 조종래;김동권;이정호;이부윤;이명렬
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1995.06a
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    • pp.25-34
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    • 1995
  • Large-scale low-alloy steel shafts, used in the manufacture of steam turbine, are produced by ingot making, forging and heat treatemtn processes. The numerical analysis techniques are introduced to analyze and design the working conditions in each process. The solidification of a steel ingot is studied through the finite element method. The open die press forging and quenching process are simulated by viscoplastic and elastic-plastic finite element method, respectively. Thus numerical analysis techniques are very useful tools to study favorable working conditions for better and more desirable product quality.

3-D Finite Element Analysis of Magnetic Force on the Arc for Design of Arc Chamber or Molded Case Circuit Breaker (배선용 차단기의 소호실 설계를 위한 Arc의 자기구동력의 3차원 해석)

  • Song, Hee-Chan;Son, Jong-Man;Kang, Sung-Wha;Lim, Kee-Joe
    • Proceedings of the KIEE Conference
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    • 1996.07c
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    • pp.1536-1540
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    • 1996
  • The Design of are quenching parts of molded case circuit breakers depends on the utilization of strength and distribution of the magnetic field by which the arc is forced. The magnetic field causes the are to move into a set of V-slotted iron grids, where the are is extinguished rapidly. This paper present the effective method 10 design V-slotted iron plates of the are breaking chamber of molded case circuit breakers. This magnetic force was calculated by using the flux densities in the arc which are obtained by three dimensional finite element method, as a result of that this paper verified by testing that a grid model which has biggest magnetic force is excellent in the are quenching ability.

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Fluorimetric Determination of Phosphate in Sea Water by Flow Injection Analysis

  • Motomizu, Shoji;Oshima, Mitsuko;Katsumura, Naoya
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.843-848
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    • 1995
  • A sensitive method for the determination of trace amounts of phosphate by fluorescence-quenching detection / FIA is proposed. The fluorescence of Rhodamine B(RB) was quenched with the formation of the ion associate of molybdophosphate with RB;${\lambda}_{ex}$ and ${\lambda}_{em}$ were 560nm and 580nm, respectively. A calibration graph was linear over the ranges from $10^{-8}$ to $3{\times}10^{-6}M$ of phosphate (~0.3~93ppb of phosphorus). The relative standard deviation was 1.2% with $8{\times}10^{-7}M$ phosphate solution and sampling rate was 15 samples / h. The proposed method was applied to the determination of phosphate in sea and river water samples.

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Computer Simulation of Quench-Hardening of Alloy Steel for Structural Purposes by the Modified Finite Difference Method (개량차분법에 의한 임의의 형상의 열처리제품의 급냉경화 해석)

  • Kim, K.S.;Song, Y.B.;Hong, C.P.
    • Journal of the Korean Society for Heat Treatment
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    • v.2 no.2
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    • pp.11-16
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    • 1989
  • Understanding and control of thermal history of heat-treated components are very important in heat treating process. A computer program was developed for prediction of thermal history in quenching process with various cooling media and agitation conditions. Computer simulation of heat flow in quenching treatment of spur gear of SCM 22 H was carried out by two and three dimensional finite difference method. Distributions of microstructure and hardness in heat-treated spur gear were predicted by computer simulation, and the results showed a good agreement with the experiments. It was concluded that the

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The study on controling curie temperature for the temperature-sensitive Magnetic materical at colling method. (냉각방법에 의한 감온자성체의 큐리온도 조정에 관한 연구)

  • Bae, Jin-Ho;Sin, Yong-Cheol;Kim, Han-Geun
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.828-830
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    • 1988
  • This paper considered temperature-sensitive characteristics on the basis of curie tempeature and quenching method in the process of manufacturing Mn-Cu-Zn Fersite. The results are as follow. Curie tempeature drops according as the content of CuO and ZnO increases. It also decreases according as sintering temperature increases when the content of ZnO in fixed. Curie temperature drops more in quenching than in slow cooling and activation energy diminishes were too. On the basis of curie tempeature, activation energy is greater in paramagnetic region than in ferrimagnetic region. As its voltage-crrent characteristics is similar to that semiconductors, the temperature-sensitive ferrite is expeated to be appied in the area of power electronics.

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