• Title/Summary/Keyword: melting time

Search Result 590, Processing Time 0.03 seconds

Design of High Frequency Casting Machine for Dental using Induction Heating System (유도가열 시스템을 적용한 치과용 고주파 주조기 설계)

  • Song, Seung-Gun;Lim, Sang-Kil;Lee, Sang-Hun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.26 no.8
    • /
    • pp.79-87
    • /
    • 2012
  • Currently, The method to produce a brewing body for dentistry supplementation water produces a brewing body by fabrication, burying and it is heat wish in city gas and oxygen. It uses an original judgment found airplane the brewing body uses a spring of the back wait that melting temperature dissolved various alloys in by a blow pipe, and to generate centrifugal force and produces it. In addition, because it uses preheating to dissolve an alloy in general, it is hard to regulate the appropriate melting temperature of the alloy and brewing time and generates a brewing defect hereby same as gas industry and pinhole and shows the defect of the supplementation thing due to the super-heating. In this paper, We developed the high induction heating system which it could set brewing time,temperature and had durability and security,by the kind of the alloy to produce a high quality prosthetic thing brewing body.

Microstructural Control of Al-Sn Metal Bearing Alloy with Heat Treatment (열처리에 따른 메탈베어링용 Al-Sn 합금의 미세조직 제어)

  • Kim, Jin-Soo;Park, Tae-Eun;Hahn, Chun-Feng;Sohn, Kwang-Suk;Kim, Dong-Gyu
    • Journal of Korea Foundry Society
    • /
    • v.29 no.1
    • /
    • pp.45-51
    • /
    • 2009
  • Conventionally, Al-Sn bearing manufacturing involves casting the Al-Sn alloy and roll-bonding to a steel backing strip. This article will describe the microstructural control of Al-Sn metal bearing alloy following heat treatment. When the pure aluminum rod dipped in the melt of tin maintained below the melting point of aluminum, the melting of aluminum was accelerated with penetration of tin along the grain boundary of aluminum. The length of plate-shaped eutectic tin was decreased with heat treatment time. With even longer heat treatment time over 1 hour the length of eutectic tin didn't decrease any more, while resulting in coarsening of aluminum matrix. Exuded liquid of eutectic tin was formed at the surface of Al-Sn alloy after heat treatment even at below eutectic temperature.

Property of Carboxylic Polyester Powder Coatings with Different Hardeners (경화제에 따른 열경화성 분체도료의 물성 비교)

  • Choi, Seung-Ok;Kim, Eun-Mi;Yoo, Jung-Hee;Jeong, Noh-Hee
    • Journal of the Korean Applied Science and Technology
    • /
    • v.28 no.3
    • /
    • pp.351-358
    • /
    • 2011
  • It was researched to be alternative of TGIC type hardener with human hazard element as PT 910 mix powder paint with hardener. Generally PT 910 was compared with TGIC & Epoxy resin of hardener to be used at thermosetting powder paint. We inquired a property of matter for paint through Gel time, glass transition temperature, melting point and a property of matter for film through a property of adhesion, a property of tolerance, softness, gloss, acid-resistant, alkali-resistant, salt water spray-resistant, facilitation climatic. When PT 910 is used of hardener, it was shown the excellent results in gel time, softness, salt water spray-resistant, fracilitation climatic and the similar results in melting point, a property of tolerance, a property of adhesion, gloss, acid-resistant, alkali-resistant, as compared with the powder paint used by TGIC hardener. The glass transition temperature was little low. But there was slightly different results. After the study results, we reached the conclusion that thermosetting powder used by PT 910 is alterative to by TGIC hardener.

Analysis with Directional Solidification in Silicon Melting Process (실리콘 용융 공정에서 방향성 응고에 관한 특성 분석)

  • Cho, Hyun-Seob
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.15 no.3
    • /
    • pp.1707-1710
    • /
    • 2014
  • This paper is the study for the directional solidification of the ingot through the thermal analysis simulation and structural change of casting furnace. The activation analysis of metal impurities were also detected the total number of 10 different metals, but the concentration distribution showed no significant positional deviations in the same position from the top to the bottom. With the results of thermal analysis simulation, the silicon as a whole has reached the melting temperature as the retention time 80 min. The best cooling conditions showed at the upper cooling temperature 1,400C and cooling time 60min. The fabricated wafers showed the superior etching result at the grain boundary than that of existing commercial wafers.

Effect of Sintering Conditions on the Microstructure of an FeCrMnNiCo High-Entropy Alloy (소결 조건에 따른 FeCrMnNiCo 고엔트로피 합금의 미세조직 변화)

  • Seonghyun Park;Sang-Hwa Lee;Junho Lee;Seok-Jae Lee;Jae-Gil Jung
    • Journal of Powder Materials
    • /
    • v.31 no.5
    • /
    • pp.406-413
    • /
    • 2024
  • We investigated the microstructure of an FeCrMnNiCo alloy fabricated by spark plasma sintering under different sintering temperatures (1000-1100℃) and times (1-600 s). All sintered alloys consisted of a single face-centered cubic phase. As the sintering time or temperature increased, the grains of the sintered alloys became partially coarse. The formation of Cr7C3 carbide occurred on the surface of the sintered alloys due to carbon diffusion from the graphite crucible. The depth of the layer containing Cr7C3 carbides increased to ~110 ㎛ under severe sintering conditions (1100℃, 60 s). A molten zone was observed on the surface of the alloys sintered at higher temperatures (>1060℃) due to severe carbon diffusion that reduced the melting point of the alloy. The porosity of the sintered alloys decreased with increasing time at 1000℃, but increased at higher temperatures above 1060℃ due to melting-induced porosity formation.

The Critical Characteristics Attributed to the Slow Cooling and Annealing Time in the Melting Growth (용융성장시 서냉시간과 후열처리시간에 따른 임계특성)

  • 임성훈;최명호;강형곤;정동철;박종광;한병성
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.11 no.4
    • /
    • pp.327-333
    • /
    • 1998
  • The influence of slow cooling and annealing time in O2in MPEG process on Jc was investigated. From the measurement of Jc,SEM and XRD, it was observed that the critical current density was related with the slow cooling time and annealing time in O2. The value of Jc was the highest at slow cooling time of 40 hour. And also, the value of Jc along the annealing time in O2in the case of the slow cooling time of 40 hours was inclined to increase with annealing time. Consequently, it can be suggested that proper slow cooling time and annealing time after slow cooling in MPMG process be important to improve the critical characteristics.

  • PDF

Identification of Brucella melitensis isolates originating from Mongolia and diagnostic real-time PCR evaluation using a specific SNP (몽골 유래 Brucella melitensis 동정 및 특이 SNP를 이용한 real-time PCR법에 의한 진단 평가)

  • Kang, Sung-Il;Kim, Ji-Yeon;Kim, Suk Mi;Lee, Jin Ju;Sung, So-Ra;Kim, Yeon-Hee;Jung, Suk Chan;Her, Moon
    • Korean Journal of Veterinary Research
    • /
    • v.55 no.2
    • /
    • pp.105-110
    • /
    • 2015
  • A real-time PCR assay using hybridization probe (HybProbe) has been developed to detect Brucella (B.) melitensis strains. The primer and HybProbe sets were designed based on the gap gene of chromosome I with a specific single nucleotide polymorphism of B. melitensis. Specificity of the assay was confirmed by comparison to reference Brucella species and other related strains. In the melting curve analysis, B. melitensis generated a peak at 67C unlike those for other Brucella species observed at 61C. Sensitivity of the assay for B. melitensis ranged from 20 ng to 200 fg of genomic DNA. The ability to identify 94 Mongolian B. melitensis isolates using the real-time PCR assay was identical to that of classical biotyping methods and differential multiplex PCR. These data showed that this new molecular technique is a simple and quick method for detecting B. melitensis, which will be important for the control and prevention of brucellosis.

Analysis of the Melting Characteristics of a Blade Type Fuse Used for Vehicles Due to Overload (과부하에 따른 차량용 블레이드형 퓨즈의 용단특성 해석)

  • Choi, Chung-Seog
    • Fire Science and Engineering
    • /
    • v.24 no.2
    • /
    • pp.38-43
    • /
    • 2010
  • The purpose of this study is to secure the basis for judgment on the cause of an accident by analyzing the melting characteristics of a blade type fuse used for vehicles due to overload. In order to increase the reliability of the test, it was conducted by connecting the electrical system with conditions similar to those of an actual vehicle to apply the load. Carbonization pattern experiment of fuse by outside flame applied Korean Standard (KS). The fuse melted by the overcurrent showed a smooth cross-section while the test terminals, clear plastic body, etc., burnt out by the external flame was badly deformed. When 185% of the rated current (27.8A) was applied to a cable of 15A rated current onto which an over-capacity fuse (20A) was installed, the fuse melting time was 217 seconds. In addition, when a load current of 28.8[A] (139%) was applied, the fuse's test terminal and terminal blade were not burnt out although foam was observed on some parts of the plastic body. When a load capacity of 28.2[A] (141%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melting time was approximately 10 seconds. When a load current of 35.8[A] (119%) was applied, the fuse's test terminal and terminal blade were not burnt out, although some parts of the plastic body was swelled. However, it was observed that the switch terminal melted if approximately six minutes lapsed under such conditions. When a load capacity of 39.4[A] (131%) was applied to a cable of 15A rated current onto which an over-capacity fuse (30A) was installed, the fuse melted in approximately 69 seconds, and the test terminal and terminal blade were not burnt.

A Study on the Soldering Characteristics of Sn-Ag-Bi-In Ball in BGA (Sn-Ag-Bi-In계 BGA볼의 솔더링 특성 연구)

  • 문준권;김문일;정재필
    • Journal of Welding and Joining
    • /
    • v.20 no.4
    • /
    • pp.505-509
    • /
    • 2002
  • Pb is considered to be eliminated from solder, due to its toxicity. However, melting temperatures of most Pb-free solders are known higher than that of Sn37Pb. Therefore, there is a difficulty to apply Pb-free solders to electronic industry. Since Sn3Ag8Bi5In has relatively lower melting range as 188 200C, on this study. Wettability and soldering characteristics of Sn3Ag8Bi5In solder in BGA were investigated to solve for what kind of problem. Zero cross time, wetting time, and equilibrium force of Sn3Ag8Bi5In solder for Cu and plated Cu such as Sn, Ni, and Au/Ni-plated on Cu were estimated. Plated Sn on Cu showed best wettability for zero cross time, wetting time and equilibrium farce. Shear strength of the reflowed joint with Sn3Ag8Bi5In ball in BGA was investigated. Diameter of the ball was 0.5mm, UBM(under bump metallurgy) was Au(0.5μm)Ni(5μm)/Cu(18μm) and flux was RMA type. For the reflow soldering, the peak reflow temperature was changed in the range of 220 250C, and conveyor speed was 0.6m/min.. The shear strength of Sn3Ag8Bi5In ball showed similar level as those of Sn37Pb. The soldered balls are aged at 110C for 36days and their shear strengths were evaluated. The shear strength of Sn3Ag8Bi5In ball was increased from 480gf to 580gf by aging for 5 days.

Evaluation of DNA Fragments on Boar Sperm by Ligation-mediated Quantitative Real Time PCR

  • Lee, Eun-Soo;Choi, Sun-Gyu;Yang, Jae-Hun;Bae, Mun-Sook;Park, Jin-Young;Park, Hong-Min;Han, Tae-Kyu;Hwang, You-Jin;Kim, Dae-Young
    • Journal of Embryo Transfer
    • /
    • v.25 no.2
    • /
    • pp.111-116
    • /
    • 2010
  • Sperm chromatin integrity is essential for successful fertilization and development of an embryo. Reported here is a quantification of DNA fragments which is intimately associated with reproductive potential to provide one of criteria for sperm chromatin integrity. Three sperm populations were considered: CONTROL (no treatment), UV irradiation (48mW/cm2, 1h) and H2O2 (oxidative stress induced by hydrogen peroxide, 10 mM, 50 mM and 100 mM). DNA fragments in boar sperm were evaluated by using ligation-mediated quantitative real-time polymerase chain reaction (LM-qPCR) assay, which relies on real-time qPCR to provide a measure of blunt 5' phosphorylated double strand breaks in genomic DNA. The results in agarose gel electrophoresis showed no significant DNA fragmentation and no dose-dependent response to H2O2. However, the remarkable difference in shape and position was observed in melting curve of LM-qPCR. This result supported that the melting curve analysis of LM-qPCR presented here, could be more sensitive and accurate than previous DNA fragmentation assay method.