간행물
한국분말야금학회지 KCI 등재 Journal of Korean Powder Metallurgy Institute
- 발행기관 한국분말재료학회(구 한국분말야금학회)
- 자료유형 학술지
- 간기 격월간
- ISSN 1225-7591 (Print)2287-8173 (Online)
- 수록기간 1994 ~ 2024
- 주제분류 공학 > 금속공학 공학 분류의 다른 간행물
- 십진분류KDC 559DDC 629
권호리스트/논문검색
Vol. 12 No. 5 (2005년 10월) 7건
1.
2005.10
구독 인증기관 무료, 개인회원 유료
Implant prototypes with various porosities were fabricated by electro-discharge-sintering of atomized spherical Ti-6Al-4V powders. Single pulse of 0.75 to 2.0 kJ/0.7 g-powder, using 150, 300, and capacitors was applied to produce a fully porous and porous surfaced implant compact. The solid core formed in the center of the compact after discharge was composed of acicular grains and porous layer consisted of particles connected in three dimensions by necks. The solid core and neck sizes increased with an increase in input energy and capacitance. On the other hand, pore volume decreased with increased capacitance and input energy due to the formation of solid core. Capacitance and input energy are the only controllable discharge parameters even though the heat generated during a discharge is the unique parameter that determines the porosity of compact. It is known that electro-discharge-sintering of spherical Ti-6Al-4V powders can efficiently produce fully-porous and porous surfaced Ti-6Al-4V implants with various porosities in a short time less then 400 isec by manipulating the discharging condition such as input energy and capacitance including powder size.
4,000원
2.
2005.10
구독 인증기관 무료, 개인회원 유료
Porous and porous surfaced Ti-6Al-4V implant compacts were fabricated by electro-discharge-sintering (EDS) of atomized spherical Ti-6Al-4V powders with a diameter of , The solid core formed in the center of the compact after discharge was composed of acicular Widmanstatten grains, The hardness value at the solid core was much higher than that at the particle interface or particles in the porous layer, which can be attributed to both heat treatment and work hardening effects induced from EDS, The compressive yield strength was in a range of 19 to 436 MPa which significantly depends on both input energy and capacitance, Selected porous-surfaced Ti-6Al-4V implant compacts with a solid core have much higher compressive strengths compared to the human teeth and sintered Ti dental implants.
3,000원
3.
2005.10
구독 인증기관 무료, 개인회원 유료
In the present study, the focus is on the effect of cobalt oxide powder in the carbothermal reduction of the titanium-cobalt-oxygen based oxide powder by solid carbon for the optimizing synthesis process of ultra fine TiC/Co composite powder. The titanium-cobalt-oxygen based oxide powder was prepared by the combination of the spray drying and desalting processes using the titanium dioxide powder and cobalt nitrate as the raw materials. The titanium-cobalt-oxygen based oxide powder was mixed with carbon black, and then this mixture was carbothermally reduced under flowing argon atmosphere. Changes in the phase structure and thermal gravity of the mixture during carbothermal reduction were analysed using XRD and TGA. Titanium-cobalt-oxygen based oxide powder desalted at had a mixture of . And the one desalted at had a mixture of . In the case of the former powder, the reduction of cobalt oxide powder in the titanium-cobalt-oxygen based oxide powder occurred at lower temperature than the latter one. However, the carbothermal reduction of titanium dioxide powder in the titanium-cobalt-oxygen based oxide powder with a mixture of occurred at higher temperature than the one with a mixture of . And also, the former powder showed a lower TiC formation ability than the latter one.
4,000원
4.
2005.10
구독 인증기관 무료, 개인회원 유료
In this study the nanostructured ceramics have been fabricated by the combined application of magnetic pulsed compaction (MPC) and subsequent spark plasma sintering (SPS), and their density and hardness properties were investigated. The prepared by the combined processes showed an increase by in density, approaching the value close to the true density, and an enhancement by in hardness, compared to those fabricated by MPC or static compaction method followed by sintering treatment.
4,000원
5.
2005.10
구독 인증기관 무료, 개인회원 유료
Nanoscale Al powder with thin layer of alumina was produced by Wire Electric Explosion (WEE) process. Spark-Plasma Sintering (SPS) was performed for the produced powder to confirm the effectiveness of SPS like so-called 'surface-cleaning effect' and so on. Crystallite size and alumina content of produced powder varied with the ratio of input energy to sublimation energy of Al wire (): Increase in () resulted in the decrease of crystallite size and the increase of alumina content. Shrinkage curve during SPS process showed that the oxide surface layer could not be destroyed near the melting point of Al. It implied that there was not enough or no spark-plasma effect during SPS for Al/Alumina powder.
4,000원
6.
2005.10
구독 인증기관 무료, 개인회원 유료
Fe-doped skutterudite with a nominal composition of has been synthesized by mechanical alloying (MA) of elemental powders, followed by hot pressing. Phase transformations during mechanical alloying and hot pressing were systematically investigated using XRD. Single phase skutterudite was successfully produced by vacuum hot pressing using as-milled powders without subsequent annealing. However, second phase in the form of marcasite structure was found to exist in case of , suggesting the solubility limit of Fe with Co in this system. Thermoelectric properties as functions of temperature and Fe contents were evaluated for the hot pressed specimens. Fe substitution up to x=1.5 with Co in appeared to increase thermoelectric figure of merit (ZT) and the maximum ZT was found to be 0.78 at 525K in this study.
4,000원
7.
2005.10
구독 인증기관 무료, 개인회원 유료
The structural and magnetic properties of nanostructued alloy powders were investigated. Commercial alloy powders (Hoeganaes Co., USA) with purities were used to fabricate the nanostructure Fe-Si alloy powders through a high-energy ball milling process. The alloy powders were fabricated at 400 rpm for 50 h, resulting in an average grain size of 16 nm. The nanostructured powder was characterized by fcc and hcp phases and exhibited a minimum coercivity of approximately 50 Oe
4,000원
