In-situ study on deformation behavior of austenite-base Duplex High Mn steels

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오스테나이트계 고 망간강의 변형 거동 연구

DoctorThe demands for developing high performance high Mn steels have been expanded in recent years since they have excellent combination of high tensile strength and elongation with the relatively effective cost. However, the deformation behavior and strengthening mechanism has not been clearly understood yet since the microstructure can consist of multi-phases depending on the alloy composition. In this regard, the study on them is needed to maximize the mechanical properties and optimize the alloy composition. Moreover, the formation and deformation mechanism of ε-martensite has to be also understood, which plays as an intermediate phase in the whole phase transformation and affects the work hardening and final mechanical properties. Furthermore, the demand for cryogenic materials has been extensively expanded in recent years, for example LNG storage tank and cryogenic offshore structure. In this regard, there are many efforts to replace the commercial Ni steels with Mn steels due to the relatively low cost and the metallurgical similarities of Mn steels with Ni steels, and austenite-base high Mn steels are promising candidate. However, the low temperature deformation behavior of high Mn steels is not clear since the deformation behavior and microstructure evolution can be quite different with the various test temperatures. In this study, the deformation behavior and strengthening mechanism of Fe-17Mn-0.02C containing ε-martensite within austenite matrix have been examined via the microstructure analysis. Moreover, in-situ neutron diffraction study was conducted to investigate the deformation behavior in detail at 298 K and 77 K. Based on the analyses of change in phase fraction and lattice strain, it has been shown that the steel shows the deformation-induced phase transformation of austenite -> ε-martensite -> α’-martensite at both temperatures. However, the kinetics of such transformation varies with temperature, resulting in a higher and more persistent work hardening at 77 K than at 298 K

Temperature dependence of mechanical properties and deformation behavior of austenite-base high Mn steels

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Effect of Heat treatment Paths on the Microstructure and Tensile Properties of High Cr Containing Ultrahigh Strength Steels

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백색 LED 구현을 위한 새로운 Sr2MgSi2O7:Eu2+와 Ca3Mg3(PO4)4:Eu2+,Mn2+형광체의 광 특성 및 에너지 전달 과정의 이해

학위논문(석사) - 한국과학기술원 : 신소재공학과, 2009.2, [ xi, 137 p. ]한국과학기술원 : 신소재공학과

Effect of Microstructure on Low Temperature Mechanical Properties of Austenite-Based High Mn Steels

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Effect of Constituent Phases on Low Temperature Deformation Behavior of Austenite-Base High Mn Steels

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NANOFIBER MESH BIOELECTRODE USING CONDUCTIVE MATERIAL AND MANUFACTURING METHOD THEREOF

본 발명은 전도성 고분자를 이용한 나노 섬유 메쉬 생체 전극 및 이의 제조방법에 관한 것이다

오스테나이트계 고 Mn강의 변형 거동 해석

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The improvement of toughness at low temperature in ferritic Fe-Mn steels

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