http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
가스분무법에 의해 급냉응고된 Al-Fe 합금분말의 응고조직
맹완영,남태운 ( Wan Young Maeng,Tae Woon Nam ) 한국주조공학회 1994 한국주조공학회지 Vol.14 No.2
N/A The Al-Fe alloy powders were rapidly solidified by gas atomization. Rapidly solidified Al-Fe alloy powders for ranges of composition from 0 to 8wt.%Fe have various microstructure, i.e., cellular, dendritic or two-zone structure. Some small particles(∼10㎛ or less) of Al-Fe alloy at concentrations between 0 and 8wt.%Fe are undercooled significantly prior to solidification and exhibit a two-zone structure in individual powder particles. X-ray diffraction patterns were obtained with Copper K(λ=1.5418Å) in diffractometer to study the extension of the solubility limit of Fe in Al. Lattice parameters were estimated from extrapolation by means of the Nelson-Riley function. The X-ray diffraction patterns for the alloy powders containing up to 4wt.%Fe do not show intensity peak of FeAl₃phase. And the diffraction angles for α Al are shifted up to 4wt.%Fe alloy powders. Thus 4wt.%Fe probably represents the limit of metastable solubility of Fe in Al solidified by gas atomization.
인코넬 합금의 열처리에 따른 입계 탄화물 석출 및 입계응력부식 거동
맹완영,남태운 ( Wan Young Maeng,Tae Woon Nam ) 한국열처리공학회 1997 熱處理工學會誌 Vol.10 No.4
Inconel alloys used as nuclear power plant components have experienced intergranular stress corrosion cracking problems inspite of their good corrosion characteristics. In order to investigate the effects of heat treatments on carbide precipitation and intergranular stress corrosion cracking(IGSCC) in Inconel alloys, DSC(Differential Scanning Calorimeter), TEM, EDXS and static potential corrosion tests were carried out. Thermal treatment at 750℃ for 15hours in Inconel alloys increased the density of intergranular carbide. The carbides are mainly Cr_7C₃ in Inconel 600, and Cr_(23)C_6 in Inconel 690. The Cr depletion around grain boundary is not crucial factor on IGSCC. The carbides in grain boundary play an important role as acting dislocation source, and as decreasing stress around growing crack.
맹완영,백정하,오인상,남태운 ( W . Y . Maeng,J . H . Bac,I . S . Oh,T . W . Nam ) 한국열처리공학회 1994 熱處理工學會誌 Vol.7 No.2
In the molten state, magnesium alloys vigousey react with oxygen in the air, is protected from oxidation and burning by the addition of SF_b to CO₂atmosphere over the melt. The mechanical properties and metallographic examinatin have made of Mg-Al alloys containing 3, 6, 9% in the solution treated state and precipitated state, comparing mechanical properties obtained during unidirectional solidification with mechanical properties obtained during conventional casting. For a given solution treatment, a higher aluminum contents produce more or less fine grains in conventional casting. For a given artifical aging treatment, a higher aluminum contents produces much precitates at the grain boundary as well as within the grain in unidirectional solidification. As a result of this experiment, for a given heat treatment, the higher is aluminum contents the higher is the ultimate tensile strength, yield strength, hardness while the lower the elongation. Also the mechanical properties of unidirectional solidification is larger than that of conventional casting.