• Title/Summary/Keyword: iron scale

Search Result 263, Processing Time 0.025 seconds

무산세 열연 용융아연도금강판의 도금밀착성에 미치는 도금욕 Al농도의 영향 (Effect of Al content on coating adhesion of hot rolled galvanized iron manufactured without pickling process)

  • 전선호;최진원
    • 한국표면공학회지
    • /
    • 제32권1호
    • /
    • pp.31-42
    • /
    • 1999
  • The effect was investigated that aluminium in the zinc bath has on the coating adhesion of Hot-rolled Galvanized Iron(HGI) manufactured without pickling process. It is thought that the coating adhesion of HGI manufactured without pickling process is good due to the fact that increasing aluminium content in the zinc bath makes zinc and aluminium diffuse to the cracks or pores in the scale formed through the reduction heat treatment, and Fe-Zn-Al compound with good ductility is formed in the scale layer and plays a role of anchor between zinc coating and substrate. It is possible that HGI with the good coating adhesion was produced without pickling treatment in the zinc bath with more that 3wt% of Al content even at the $550^{\circ}C$ of conventional reduction heating temperature. In creasing the temperature of heating section and aluminium content in the zinc bath prevents the Zn-Fe alloy. The corrosion resistance of HGI manufactured without pickling process is excellent because of the mixed reaction of zinc sacrifice and aluminium passivity film.

  • PDF

철성분 미세먼지 포집을 위한 자성 필터 연구 (Fine Iron Dust Collection by Magnetized Mesh Filters)

  • 박해우;황산;정상귀;김상범;조영민
    • 한국대기환경학회지
    • /
    • 제31권2호
    • /
    • pp.118-130
    • /
    • 2015
  • Fine dust containing iron compounds is of current interests in metro subway as well as large scale industries including iron manufacturing and smelting works. This work attempts to find a new design of magnetic filter module for iron dust capture. It simulated the vertical rectangular duct with metal mesh which might promote electric fields in the duct space. A lab test using coal fly ash composed of 8.66% Fe with the most form of $Fe_3O_4$ and $Fe_2O_3$ showed capability of magnetic collection. It showed the capture efficiency with 80~93% for $PM_{2.5}$ depending on magnetic intensity. Ferromagnetic wire mesh contributed up to 50% of collection increment.

니켈 함유 에칭폐액으로부터 용매추출에 의한 $FeCl_3$의 재생 (Regeneration of $FeCl_3$ from a Spent Etching Solution Containing Nickel by Solvent Extraction)

  • 이경주;이만승;오영주
    • 한국자원리싸이클링학회:학술대회논문집
    • /
    • 한국자원리싸이클링학회 2004년도 춘계임시총회 및 제23회 학술대회
    • /
    • pp.218-226
    • /
    • 2004
  • Solvent extraction and stripping experiments were conducted to separate iron from a spent $FeCl_3$ etching solution containing nickel. In the extraction, PC88A, MIBK and Alamine336 were tested as an extractant in various diluents. Alamine336 salt in toluene led to the highest extraction percentage of iron. Stripping percentage of iron from the loaded organic by Alamine336 increased with decreasing HCl conentration of stripping solution and with increasing volume ratio of aqueous to organic. In the operation of bench scale mixer-settler, 7 extraction stage with 1.0M Alamine336 salt in toluene and 10 stripping stage with 0.01M HCl solution resulted in a stripped solution with 133g/L of iron and in a raffinate with most of nickel together with a small amount of iron when the flow rate ratio of organic to aqueous was 7.

  • PDF

0가 철과 직류전원을 이용한 TCE 오염 지하수의 정화기법 예비조사 (Preliminary Experiments for the Remediation of Trichloroethene-Contaminated Groundwater Using Direct-Current and Zero-Valent Iron)

  • 문지원;문희수;노열;이석영;송윤구
    • 자원환경지질
    • /
    • 제34권3호
    • /
    • pp.307-313
    • /
    • 2001
  • $Fe^0$ 등의 0가 금속을 포함하는 반응재들은 오염운이 반응벽을 통과하는 동안 염소계 용매들을 분해시킨다. Fe$^{0}$ 를 이용한 투수성 반응벽은 특히 trichloroethene(TCE)이 주된 오염원인 경우 처리비용이 적다는 장점이 있는 반면, 반응속도가 느리고, 반응벽의 운영기간이 제한된다는 단점이 있다. 본 연구는 기존의 Fe$^{0}$ 를 이용한 반응벽에 직류전원을 걸어주는 향상된 처리기술 개발은 예비연구이다. $Fe^0$ 반응컬럼을 이용한 bench-scale의 실험을 통해 $Fe^0$ 반응재와 직류전원의 조합은 TCE의 탈염소화를 촉진하는 것으로 나타났다. 탈염소화의 반응기작은 철의 산화와 부가적인 전자의 공급원인 외부전원에 의한 환원에 기인한다.

  • PDF

콩 유용성분 탐색에 관한 연구: 콩 Ferritin의 정제 및 특성 (Investigation of useful components in soybean seeds: Purification and characterization of soybean ferritin)

  • 서경원;오석홍
    • Applied Biological Chemistry
    • /
    • 제41권7호
    • /
    • pp.522-526
    • /
    • 1998
  • 콩 유용성분 탐색의 일환으로 그리고 향후 콩 ferritin 항체 및 유전자 확보를 목표로 발아된 콩으로부터 ferritin을 분리 정제하여 그 몇가지 특성을 조사하였다. 72시간 발아된 콩으로부터 ammonium sulfate 침전(0.55 saturation), DEAE-cellulose, Sephacryl S-300, Bio-Scale Q2 column chromatographies를 통하여 ferritin을 분리하였다. 정제된 콩 ferritin은 SDS-PAGE 분석에서 21 kDa의 크기를 나타냈으며, Sephacry S-300을 통한 겔거르기 chromatography와 non-denaturing 폴리아크릴아마이드 전기영동 분석에서 $510{\sim}560\;kDa$의 크기로 측정 되었다. 또한, immunodiffusion test에서 anti-soybean ferritin antiserum과 상호 반응하였다. 원자흡광광도계와 표준 철 용액을 이용한 정제된 콩 ferritin 중의 철 함유량은 833 mol Fe/mol protein 이었으며, 이는 호박씨로부터 분리한 ferritin보다 31배 더 많은 양의 철 함유량 이었다. 정제된 콩 ferritin중의 철은 horse spleen ferritin 중의 철과 유사하게 iron staining 되었다.

  • PDF

철도차량용 제동 디스크의 트라이볼로지 특성 연구 (Tribological Characteristics of Brake Disc for Train)

  • 김상호;이희성
    • Tribology and Lubricants
    • /
    • 제23권1호
    • /
    • pp.19-28
    • /
    • 2007
  • Mechanical Brake system is inevitable equipment for stability of train and speed of the train. Especially brake disk and brake pads are core parts of mechanical brake system. It was investigated with tribological characteristics of brake discs for train by using lab-scale dynamometer. Gray cast iron disk was most attacked with sintered brake pad. Alloyed steel disk and NCM cast iron disk had suitable friction coefficient, high stability and low disk attack to the sintered brake pad. But at the view of economy, low alloyed cast iron will be most suitable choice.

산화철계 형석대체제의 전로 정련특성 (BOF Refining of Fluorspar Substitute Using Iron Oxide Based By-product)

  • 금창훈;허보영
    • 한국재료학회지
    • /
    • 제16권5호
    • /
    • pp.336-340
    • /
    • 2006
  • Fluorspar has been essential flux in steelmaking process. The main effects of fluorspar addition are lowering of the viscosity and melting temperature of slag. In recent years, due to the increasing price and environmental problem of fluorspar, various types of fluorspar substitute have been investigated. In this study, iron oxide by-products such as sinter dust, basic oxygen furnace (BOF) sludge and mill scale were developed as a substitute in terms of waste recycling. Several plant trials were carried out by addition of briquetted substitutes of $4{\sim}6$ kg/ton to compare with the fluorspar of $0.7{\sim}1$ kg/ton. The substitutes showed a similar behavior of slag formation, phosphorus removal and MgO saturation content.

구상흑연주철의 피로수명분포에 대한 통계적 해석 (A Statistical Analysis on Fatigue Life Distribution in Spheroidal Graphite Cast Iron)

  • 장성수;김상태
    • 대한기계학회논문집A
    • /
    • 제24권9호
    • /
    • pp.2353-2360
    • /
    • 2000
  • Statistical fatigue properties of metallic materials are increasingly required for reliability design purpose. In this study, static and fatigue tests were conducted and the normal, log-normal, two -parameter Weibull distributions at the 5% significance level are compared using the Kolmogorov-Smirnov goodness-of-fit test. Parameter estimation were compared with experimental results using the maximum likelihood method and least square method. It is found that two-parameter Weibull distribution and maximum likelihood method provide a good fit for static and fatigue life data. Therefore, it is applicable to the static and fatigue life analysis of the spheroidal graphite cast iron. The P-S-N curves were evaluated using log-normal distribution, which showed fatigue life behavior very well.

조선후기 관영건축공사에 있어서 철물과 철제 연장의 공급체계에 관한 연구 -영건의궤(營建儀軌) 기록을 중심으로- (A Study on the Supply System of Iron Materials and the Tools in Government Constructions in the Late of Joseon Dynasty)

  • 이권영;김왕직
    • 건축역사연구
    • /
    • 제16권3호
    • /
    • pp.95-114
    • /
    • 2007
  • Since the 17th century, the society of Joseon dynasty belongs to a period of rapid transition in many fields. As the building is a result to be produced on the basis of a society and economy, the general transition in a society is to be reflected into a process of building construction. Especially, a study on the material supply system of economic base in a process of building construction is one of vely important factors in an understanding or estimate of a building. On the premise, this paper is to examine the supply system of iron materials and the tools in the construction of the government managed buildings in the late of Joseon dynasty on a viewpoint of productivity. Construction reports and other documents in those days are examined for the study. Following conclusions have been reached through the study. 1) The general supply method of iron materials for a large-scale government construction was based on 'byulgong', that is, a kind of tribute. 2) Various methods were selected in the supply method of iron materials for government use in the late of Joseon dynasty. The priority order of choice in its government policy was put on an easiness of amount security, on a minimum of expenditure, and on an efficiency of construction execution. 3) The manufacturing technique of weaponry was used in the production method of iron materials and the tools for government use. The cooperation of the official, the army, and the merchant had improved the manufacturing technique of building construction.

  • PDF

혐기성 미생물부식에 의해 생성되는 철화합물 추정식 개발 (The Development of Estimation Model for Iron Compound Originated from Anaerobic Microbial Corrosion)

  • 전석준
    • 한국물환경학회지
    • /
    • 제18권4호
    • /
    • pp.379-386
    • /
    • 2002
  • In this study, estimation model for iron compound originated from upflow, anaerobic fixed bed reactor, which treats sewage domestic wastewater, was developed. The estimation model was formulated by a mathematical expression which was based on the mass balance. Below the HRT of 60 minute, sulfide concentration combining with iron $FeS_2$ is the highest because the maximum sulfate consumption rate $V_{maxS}$ and half-saturation constant of sulfate $K_{mS}$ exert an important effect on the estimation model as temperature was increased. But increment of $FeS_2$ concentration is weakened above the HRT of 60 minutes and represent the lowest value at the HRT of 108 minutes. It implies that liquid phase distribution ratio of sulfide ${\alpha}r$ becomes lower as temperature was increased. While phosphorus concentration combining with iron $Fe_3(PO_4)_3$ is increased as HRT and temperature are increased, which is affected by phosphorus removal rate constant $k_p$. As the result of estimating the iron concentrations of corrosion by the model, the concentration of iron corrosion is higher than any other at the HRT of 108 minute and $20^{\circ}C$. The predicted values were compared with measured ones at different HRT(13.5, 27, 54, 108 min) and temperature(20, 25, $30^{\circ}C$). The experimental data could be fitted with the simulated curves. Therefore, the mathematical expression could be applicable to design full-scale wastewater treatment plants.