간행물
한국분말야금학회 학술대회논문집
- 발행기관 한국분말재료학회(구 한국분말야금학회)
- 자료유형 학술대회
- 간기 부정기
- 수록기간 1993 ~ 2006
- 주제분류 공학 > 금속공학 공학 분류의 다른 간행물
- 십진분류KDC 559DDC 629
권호리스트/논문검색
한국분말야금학회 2006년도 춘계학술대회논문집 (2006년 4월) 443건
61.
2006.04
구독 인증기관·개인회원 무료
Lee Jong-Keuk, Hong Soon-Jik, Lee Min-Ku, Rhee Chang-Kyu, Jeong Soo-Jong, Park Jin-Sung, Park Jun-Sung
62.
2006.04
구독 인증기관·개인회원 무료
63.
2006.04
구독 인증기관·개인회원 무료
Hwang, S.Y., Kim, J.H., Kim, H.J., Seong, B.G., Jun, H.W., Lee, H.W., Seok, H.K., Lee, C., Yang, H., Baik, K.H.
64.
2006.04
구독 인증기관·개인회원 무료
Porosity in spray-formed materials is an important issue, but the formation of porosity is not completely understood. The paper gives some examples picked from literature, which show some general correlations between process parameters and porosity. To improve the understanding of porosity formation it is necessary to know more about the conditions of the droplets and the deposit at the point of impingement. Determining the impact conditions is a challenge because usually they are not constant with time and some values are difficult to measure. Our experiments show a strong correlation between the deposit surface temperature and the porosity. The average impact angle weighted by the local particle mass flux is also an important parameter.
65.
2006.04
구독 인증기관·개인회원 무료
66.
2006.04
구독 인증기관·개인회원 무료
67.
2006.04
구독 인증기관·개인회원 무료
In Spray Forming, specific enthalpy is a key parameter in the deposition process as it influences the thermal condition of the impinging droplets as well as that of the deposit surface. An empirical model for the distribution of specific enthalpy in the spray cone was developed as an easy to handle alternative to numerical models with which the descriptive partial differential equations are solved numerically. The model results were compared with the experimental data to validate its applicability.
68.
2006.04
구독 인증기관·개인회원 무료
69.
2006.04
구독 인증기관·개인회원 무료
In this contribution, we attempted a theoretical analysis on the validity of the widely-accepted idea that rough and singular surfaces can coexist in a crystal at equilibrium. By manipulating the Cahn and Hoffman capillarity vector, the conclusion that a crystal at equilibrium should be composed either of singular surfaces or of rough ones was reached.
70.
2006.04
구독 인증기관·개인회원 무료
71.
2006.04
구독 인증기관·개인회원 무료
Both densification and grain growth are driven by the reduction of the interfacial area, kinetics of which depends strongly on the interface structure. Abnormal grain coarsening in the system of singular solid/liquid interface such as WC-Co alloys was explained by the growth mechanism of 2-dimensional nucleation. Based on this concept, the marked inhibition of coarsening of WC grains by VC addition can be approached by the increase in the step free energy, which increases the barrier of 2-dimensional nucleation. The activated sintering in tungsten powders can be approached by the interface structure change induced by the addition of a small amount of nickel.
72.
2006.04
구독 인증기관·개인회원 무료
73.
2006.04
구독 인증기관·개인회원 무료
Anisotropic constitutive equations for sintering of metal powder compacts have been formulated from a linear viscous transversely-isotropic model in which an anisotropic sintering stress has been introduced to describe free sintering densification kinetics. The identification of material parameters defined in the model, has been achieved from thermomechanical experiments performed on 316L stainless steel warm-compacted powder in a dilatometer allowing controlled compressive loading.
74.
2006.04
구독 인증기관·개인회원 무료
75.
2006.04
구독 인증기관·개인회원 무료
76.
2006.04
구독 인증기관·개인회원 무료
The master sintering curve (MSC) is derived from densification data over a range of heating rates and temperatures. To improve the accuracy, several modifications were proposed: multi-phase MSC for solid state sintering with phase changes, MSC for liquid phase sintering, and MSC with consideration of grain growth. The developed MSC models were applied to several material systems such as molybdenum, stainless steels, and tungsten heavy alloys (WHA), in order to evaluate the effect of compaction pressure, phase change, grain growth, and composition on densification, to classify regions having different sintering mechanism, and to help engineer design, optimize, and monitor sintering cycles.
77.
2006.04
구독 인증기관·개인회원 무료
When an alloy such as Ni-W is liquid phase sintered, heavy solid W particles sedimentate to the bottom of the container, provided that their volume fraction is less than a critical value. The sintering process evolves typically in two stages, diffusiondriven macrosegregation sedimentation followed by true sedimentation. During macrosegregation sedimentation, the overall solid volume fraction decreases concurrently with elimination of liquid concentration gradient. However, in the second stage of true sedimentation, the average solid volume fraction in the mushy zone increases with time. It is proposed that the true sedimentation results from particle rearrangement for higher packing efficiency.
78.
2006.04
구독 인증기관·개인회원 무료
79.
2006.04
구독 인증기관·개인회원 무료
80.
2006.04
구독 인증기관·개인회원 무료
Growth behavior and kinetics of grains in a liquid matrix has been studied by computer simulation for various physical and processing conditions. The kinetics of growing and dissolving grains were considered to follow those of single crystals in a matrix. Depending on the shape of crystals, rounded or faceted, different kinetic equations were adopted for growing grains and an identical equation for dissolving grains. Effects of such critical parameters as step free energy, temperature, and liquid volume fraction were evaluated.
