• Title/Summary/Keyword: powder-in-tube

Search Result 213, Processing Time 0.037 seconds

Development of Porous Metal Materials and Applications

  • Fang, Y.;Wang, H.;Zhou, Y.;Kuang, C.
    • Proceedings of the Korean Powder Metallurgy Institute Conference
    • /
    • 2006.09a
    • /
    • pp.599-600
    • /
    • 2006
  • This paper described the state of art of porous metal materials, the typical manufacturing technologies and performances of sintered metal porous materials, with emphasis on the recent research achievements of CISRI in development of porous metal materials. High performance porous metal materials, such as metallic membrane, sub-micron asymmetric composite porous metal, large dimensional and structure complicated porous metal aeration cones and tube, metallic catalytic filter elements, lotus-type porous materials, etc, have been developed. Their applications in energy industry, petrochemical industry, clean coal process and other industrial fields were introduced and discussed.

  • PDF

Heat Treatment of Cu0.9In0.7Ga0.3Se2 Powder Layer with a Mixture of Selenium and Ceramic Powder (셀레늄과 세라믹 혼합분말을 사용한 Cu0.9In0.7Ga0.3Se2 분말층의 소결거동 연구)

  • Song, Bong-Geun;Hwang, Yoonjung;Park, Bo-In;Lee, Seung Yong;Lee, Jae-Seung;Park, Jong-Ku;Lee, Doh-Kwon;Cho, So-Hye
    • Current Photovoltaic Research
    • /
    • v.2 no.3
    • /
    • pp.115-119
    • /
    • 2014
  • $Cu(In,Ga)Se_2$ (CIGS) thin films have been used as a light absorbing layer in high-efficiency solar cells. In order to improve the quality of the CIGS thin film, often selenization step is applied. Especially when the thin film was formed by non-vacuum powder process, selenization can help to induce grain growth of powder and densification of the thin film. However, selenization is not trivial. It requires either the use of toxic gas, $H_2Se$, or expensive equipment which raises the overall manufacturing cost. Herein, we would like to deliver a new, simple method for selenization. In this method, instead of using a costly two-zone furnace, use of a regular tube furnace is required and selenium is supplied by a mixture of selenium and ceramic powder such as alumina. By adjusting the ratio of selenium vs. alumina powder, selenium vaporization can be carefully controlled. Under the optimized condition, steady supply of selenium vapor was possible which was evidently shown by large grain growth of CIGS within a thin powder layer.

Study for multi-filament drawing of Bi2223 high-temperature superconductivity wire by FE method (유한요소법에 의한 Bi2223 고온 초전도 선재의 다심 인발에 대한 연구)

  • 박동인;김병민;오상수
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2003.10a
    • /
    • pp.273-276
    • /
    • 2003
  • High-temperature superconduction materials(Bi2223) possess electrical/electronic and magnetic properties. Because high-temperature superconduction materials is a ceramic powder, that can not be produced singlehandedly. So Ag sheathed Bi-2223 wire was produced by drawing process using powder-in-tube(PIT) method. This superconductor has many difficulties to produce. The main difficulty is that the mechanical properties of the ceramic powder are very different from those of the Ag sheath. Bi2223 high-temperature superconductivity have a single filament drawing process, and multi-filament drawing process. This study analysed multi-filament drawing process by FEM, a defects during multi-filament drawing was studied by FEM.

  • PDF

Microstructure of ZnO Thin Film on Nano-Scale Diamond Powder Using ALD (나노급 다이아몬드 파우더에 ALD로 제조된 ZnO 박막 연구)

  • Park, S.J.;Song, S.O.
    • Journal of the Korean Vacuum Society
    • /
    • v.17 no.6
    • /
    • pp.538-543
    • /
    • 2008
  • Recently a nano-scale diamond is possible to manufacture forms of powder(below 100 nm) by new processing of explosion or deposition method. Using a sintering of nano-scale diamond is possible to manufacture of grinding tools. We have need of a processing development of coated uniformly inorganic to prevent an abnormal grain growth of nano-crystal and bonding obstacle caused by sintering process. This paper, in order to improve the sintering property of nano-scale diamond, we coated ZnO thin films(thickness: $20{\sim}30\;nm$) in a vacuum by ALD(atomic layer deposition) Economically, in order to deposit ZnO all over the surface of nano-scale diamond powder, we used a new modified fluidized bed processing replaced mechanical vibration effect or fluidized bed reactor which utilized diamond floating owing to pressure of pulse(or purge) processing after inserted diamond powders in quartz tube(L: 20 mm) then closed quartz tube by porosity glass filter. We deposited ZnO thin films by ALD in closed both sides of quartz tube by porosity glass filter by ALD(precursor: DEZn($C_4H_{10}Zn$), reaction gas: $H_2O$) at $10^{\circ}C$(in canister). Processing procedure and injection time of reaction materials set up DEZn pulse-0.1 sec, DEZn purge-20 sec, $H_2O$ pulse-0.1 sec, $H_2O$ purge-40 sec and we put in operation repetitive 100 cycles(1 cycle is 4 steps) We confirmed microstructure of diamond powder and diamond powder doped ZnO thin film by TEM(transmission electron microscope) Through TEM analysis, we confirmed that diamond powder diameter was some $70{\sim}120\;nm$ and shape was tetragonal, hexagonal, etc before ALD. We confirmed that diameter of diamond powders doped ZnO thin film was some $70{\sim}120\;nm$ and uniform ZnO(thickness: $20{\sim}30\;nm$) thin film was successfully deposited on diamond powder surface according to brightness difference between diamond powder and ZnO.

Development of 80 kW RF Thermal Plasma Torch System for Mass Production and Research of Si Nano-Powder Manufacturing Process (양산용 80 kW급 RF Plasma Torch System 개발 및 Si 나노분말 제조 공정 연구)

  • Song, Seok-Kyun;Son, Byungkoo;Kim, Byunghoon;Lee, Moonwon;Sin, Myungsun;Choi, Sunyong;Lee, Kyu-Hang;Kim, Seong-In
    • Journal of the Korean Vacuum Society
    • /
    • v.22 no.2
    • /
    • pp.66-78
    • /
    • 2013
  • In order to develop of 80 kW RF plasma torch system, we achieved three-dimensional simulations for the extraction of more information as temperature in torch and fluid behavior analysis, etc. The position of powder injection tube, the plasma discharge characteristics with various input current and various length of ceramic tube, and the plasma temperature characteristics with process gas flow rate such those was simulated. RF thermal plasma torch designed by simulation was manufactured that was measured to the maximum of 89.3 kW power. The mass production using developed 80 kW RF thermal plasma torch system were investigated by characteristics manufactured of Si nano powder. The mass-production level of Si nano-powder was average of 539 g/hr and high yield rate of 71.6%, respectively. The particle size distribution $D_{99}/D_{50}$ of manufacturing nano-powder was investigated to 1.98 as a good uniform.

Shape Control of Anodic Aluminum Oxide and Effect as Support of Silicon Powder Electrode (양극산화알루미늄의 형상제어와 이를 이용한 실리콘 분말 전극 지지체 효과)

  • Song, Ju-Seok;Ha, Jong-Keun;Kim, Yoo-Young;Park, Dong-Kyu;Ahn, In-Shup;Ahn, Jou-Hyeon;Cho, Kwon-Koo
    • Journal of Powder Materials
    • /
    • v.22 no.4
    • /
    • pp.240-246
    • /
    • 2015
  • Anodic aluminum oxide (AAO) has been widely used for the development and fabrication of nano-powder with various morphologies such as particle, wire, rod, and tube. So far, many researchers have reported about shape control and fabrication of AAO films. However, they have reported on the shape control with different diameter and length of anodic aluminum oxide mainly. We present a combined mild-hard (or hard-mild) anodization to prepare shape-controlled AAO films. Two main parameters which are combination mild-hard (or hard-mild) anodization and run-time of voltage control are applied in this work. The voltages of mild and hard anodization are respectively 40 and 80 V. Anodization was conducted on the aluminum sheet in 0.3 mole oxalic acid at $4^{\circ}C$. AAO films with morphologies of varying interpore distance, branch-shaped pore, diameter-modulated pore and long funnel-shaped pore were fabricated. Those shapes will be able to apply to fabricate novel nano-materials with potential application which is especially a support to prevent volume expansion of inserted active materials, such as metal silicon or tin powder, in lithium ion battery. The silicon powder electrode using an AAO as a support shows outstanding cycle performance as 1003 mAh/g up to 200 cycles.

Sintering of Fe-30 wt% TiC Composite Powders Fabricated from (Fe, TiH2, C) Powder Mixture ((Fe, TiH2, C) 혼합 분말로부터 제조된 Fe-30 wt% TiC 복합재료 분말의 소결)

  • Lee, Byunghoon;Kim, Ji Soon
    • Journal of Powder Materials
    • /
    • v.22 no.5
    • /
    • pp.356-361
    • /
    • 2015
  • Fe-30 wt% TiC composite powders are fabricated by in situ reaction synthesis after planetary ball milling of (Fe, $TiH_2$, Carbon) powder mixture. Two sintering methods of a pressureless sintering and a spark-plasma sintering are tested to densify the Fe-30 wt% TiC composite powder compacts. Pressureless sintering is performed at 1100, 1200 and $1300^{\circ}C$ for 1-3 hours in a tube furnace under flowing argon gas atmosphere. Spark-plasma sintering is carried out under the following condition: sintering temperature of $1050^{\circ}C$, soaking time of 10 min, sintering pressure of 50 MPa, heating rate of $50^{\circ}C/min$, and in a vacuum of 0.1 Pa. The curves of shrinkage and its derivative (shrinkage rate) are obtained from the data stored automatically during sintering process. The densification behaviors are investigated from the observation of fracture surface and cross-section of the sintered compacts. The pressureless-sintered powder compacts are not densified even after sintering at $1300^{\circ}C$ for 3 h, which shows a relative denstiy of 66.9%. Spark-plasma sintering at $1050^{\circ}C$ for 10 min exhibits nearly full densification of 99.6% relative density under the sintering pressure of 50 MPa.

The Effect of HEMM on Microstructure and Mechanical Properties of Ti-Nb Alloy for Implant Biomedical Materials (생체의학 임플란트재료로서 Ti-Nb계 합금의 조직과 기계적 성질에 미치는 HEMM의 영향)

  • Woo, Kee-Do;Choi, Gab-Song;Lee, Hyun-Bum;Kim, In-Yong;Zhang, Deliang
    • Korean Journal of Materials Research
    • /
    • v.17 no.11
    • /
    • pp.587-592
    • /
    • 2007
  • Al-42wt%Nb powder was prepared by high-energy mechanical milling(HEMM). The particle size, phase transformation and microstructure of the as-milled powder were investigated by particle size distribution (PSD) analyzer, scanning electron microscopy (SEM), X-ray diffractometery (XRD), transmission electron microscopy (TEM)and differential thermal analysis (DTA). The milled powders were heated to a sintering temperature at 1000C with under vaccum with vaccum tube furnace. Microstructural examination of sintered Ti-42wt%Nb alloy using 4h-milled powder showed Ti-rich phases (${\alpha}$-Ti) which are fine and homogeneously distributed in the matrix (Nb-rich phase: ${\beta}$-Ti). The sintered Ti-42wt%Nb alloy with milled powder showed higher hardness. The microstructure of the as quenched specimens fabricated by sintering using mixed and milled powder almost are same, but the hardness of as quenched specimen fabricated by using mixed powder increased due to solution hardening of Nb in Ti matrix. The aging effect of these specimens on microstructural change and hardening is not prominent.

Magnetic Abrasive Polishing for Internal Face of Seamless Stainless Steel Tube Using Sludge Abrasive Grain (슬러지 연마입자를 이용한 이음매 없는 스테인리스강 튜브내면의 자기연마)

  • Kim, Hee-Nam;Yun, Yeo-Kwon;Kim, Sang-Baek;Choi, Hee-Sung
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.12 no.6
    • /
    • pp.151-157
    • /
    • 2004
  • In this paper deals with behavior of the magnetic abrasive using sludge on polishing characteristics in a new internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. The magnetic abrasive using sludge-abrasive grain WA and GC used to resin bond fabricated low temperature. And sludge of magnetic abrasive powder fabricated that sludge was crused into 200 mesh. The previous research have made an experiment in the static state the movement of magnetic abrasive grain is nevertheless in the dynamic state. In this paper, We could have investigated into the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.

Characteristics of Bi(Pb)-Sr-Ca-Cu-O Superconductor Wire Fabricated using the Billet Insertion Method (Billet 장입 방식을 이용 제조한 Bi(Pb)-Sr-Ca-Cu-O 초전도 선재의 특성)

  • 장건익;유재근;홍계원
    • Journal of the Korean Ceramic Society
    • /
    • v.33 no.4
    • /
    • pp.471-477
    • /
    • 1996
  • During Bi(Pb)-Sr-Ca-Cu-O superconductor wire fabrication the effect of the initial packing density on the final characteristics of superconductor wire was systematically studied. To increase the powder packing density with uniform distribution of superconducting core a billet insertion method processed by CIP was applied instead of the commonly used vibration and ramming method of powder insertion into silver sheath. Compared with the vibration and ramming method the billent insertion technique processed by CIP cause the 30% incre-specimen with 130${\mu}{\textrm}{m}$(core thickness : 45 ${\mu}{\textrm}{m}$)and 5.24 mm width processed at 84$0^{\circ}C$for 200hrs. shows specimen with 130${\mu}{\textrm}{m}$ (core thickness ; 45${\mu}{\textrm}{m}$)and 5.24 mm width processed at 84$0^{\circ}C$ for 200 hrs. shows maximum 34A for Ic and 16, 700 A/cm2 for Ic measured at 77K and 0T. Also the sample rolled 3 times shows maximum 7, 2A for Ic and 11, 000 A/cm2 for 77K and 0T. Based on X-ray experimental results the formation of Bi-2223 and texture were significantly well developed at the interface between the superconducting core and silver sheath as compared with those of the interior area of superconducting core.

  • PDF