• 제목/요약/키워드: mechanical energy

Search Result 9,890, Processing Time 0.046 seconds

Public-Private Cooperation in the Package Deal for Overseas Energy Resources Acquisition (에너지자원획득을 위한 패키지딜 적용시 민관협력 강화 방안)

  • Park, Dae-Young;Hur, Jin-Huek;Lee, Tae-Gu;Moon, Seung-Jae;Lee, Jae-Heon;Yoo, Hoseon
    • Plant Journal
    • /
    • v.4 no.2
    • /
    • pp.73-78
    • /
    • 2008
  • The public-private cooperation in package deal has been studied for the overseas energy resources acquisition. The effectiveness of the package deal has not been successful because the deal has led by the government organizations. It is difficult for the plant EPC companies to join the packaged deal due to the lack of the whole responsibility organization to support the participation of the package deal. The followings are suggested as the ways to strengthen of the public-private cooperation in this study. 1) the relevant public enterprise privatization 2) establishment of the joint model for leading the plant EPC companies to the package deal 3) establishment of the whole responsibility organization for the public-private cooperation.

  • PDF

Microstructural evolution and mechanical properties of TiC-Mo2C-WC-Ni multi-component powder by high energy ball milling

  • Jeong-Han Lee;Hyun-Kuk Park
    • Journal of Ceramic Processing Research
    • /
    • v.22 no.5
    • /
    • pp.590-596
    • /
    • 2021
  • The widespread use of TiC-based cermets as cutting tools, thin-film, ultracapacitors, nozzles, and bearings is primarily due to exhibit combination of excellent mechanical properties such as low density, high hardness, and stiffness. The TiC cermets were synthesized by high energy ball milling, which includes binder metal (Ni), carbides (WC and Mo2C), wherein the present study focus on the relationship between the core-rim structure, phase constitution, and mechanical properties. Here, using in situ TEM, we clearly observed the behavior of adjacent core-rim formation from the solid-phase reaction with grain refinement of the TiC phase control of both the milling time and lattice formation. Also, we proposed that mechanically alloyed core-rim structure can affect oxidation resistance of TiC-Mo2C-WC-Ni cermets strongly related to activation energy attributed to TiC particle size. The mechanical properties of TiC-Mo2C-WC-Ni cermets suggest the hardening effect is not considered only grain refinement, but rather is solid solution strengthening and particle-dispersion hardening. The present study paves the relation to the formation behavior of both TiC hard phase and core-rim structure due to the mechanical powder synthesis of novel TiC-based cermets.

Prediction the Phase Transformation Time of Binary Alloy System by calculating the Input Energy of Mechanical Alloying (기계적 합금화 투입에너지 계산에 의한 이원합금계의 상변태 시간 예측)

  • Park, Dong-Kyu;Ahn, In-Shup
    • Journal of Powder Materials
    • /
    • v.26 no.2
    • /
    • pp.107-111
    • /
    • 2019
  • The activation energy to create a phase transformation or for the reaction to move to the next stage in the milling process can be calculated from the slop of the DSC plot, obtained at the various heating rates for mechanically activated Al-Ni alloy systems by using Kissinger's equation. The mechanically activated material has been called "the driven material" as it creates new phases or intermetallic compounds of AlNi in Al-Ni alloy systems. The reaction time for phase transformation by milling can be calculated using the activation energy obtained from the above mentioned method and from the real required energy. The real required energy (activation energy) could be calculated by subtracting the loss energy from the total input energy (calculated input energy from electric motor). The loss energy and real required energy divided by the reaction time are considered the "metabolic energy" and "the effective input energy", respectively. The milling time for phase transformation at other Al-Co alloy systems from the calculated data of Al-Ni systems can be predicted accordingly.

유한요소법을 이용한 조선조식 종형 구조물의 동적 해석

  • 정석주;공창덕;염영하
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.9 no.3
    • /
    • pp.309-318
    • /
    • 1985
  • 본 논문에서는 종형 구조물의 특미인 비대칭성을 고헌할 수 있고 굽힘에너지 (flexural energy)와 확장에너지(extension energy)를 모두 고헌하여 유한요소의 분할 이 용역한 사변형과 삼각형 판-셸 유한요소를 사용하였다.