CAJ | 학술논문

利用光学显微镜、XRD衍射分析仪、扫描电子显微镜、透射电子显微镜、万能拉伸试验机等仪器设备研究了Mg-4Y-2.5Nd-0.6Zr合金铸态、固溶态和峰时效态的微观组织、室温和高温力学特性及断裂行为。结果表明：合金的铸态组织主要由α-Mg、Mg41Nd5和Mg24Y5组成；经固溶处理，共晶组织完全溶入基体，仅残余方块相Mg24Y5；再经时效处理，晶内弥散析出大量β″和β′相，有效强化了合金，对应的室温抗拉强度、屈服强度和伸长率分别为292、215 MPa和4%；随着拉伸温度的提高，峰时效态合金的强度逐渐降低、伸长率逐渐增加，室温断裂类型为解理断裂，而250℃的断裂方式表现为准解理断裂。
이용광학현미경、XRD연사분석의、소묘전자현미경、투사전자현미경、만능랍신시험궤등의기설비연구료Mg-4Y-2.5Nd-0.6Zr합금주태、고용태화봉시효태적미관조직、실온화고온역학특성급단렬행위。결과표명：합금적주태조직주요유α-Mg、Mg41Nd5화Mg24Y5조성；경고용처리，공정조직완전용입기체，부잔여방괴상Mg24Y5；재경시효처리，정내미산석출대량β″화β′상，유효강화료합금，대응적실온항랍강도、굴복강도화신장솔분별위292、215 MPa화4%；수착랍신온도적제고，봉시효태합금적강도축점강저、신장솔축점증가，실온단렬류형위해리단렬，이250℃적단렬방식표현위준해리단렬。
Microstructures,mechanical properties and fracture behaviors of Mg-4Y-2.5Nd-0.6Zr alloy at different states were investigated by Optical Microscope(OM),X-ray Diffractometer(XRD),Scanning Electron Microscope(SEM),Transmission Electron Microscope(TEM)and universal tensile test machine. Results show that the as-cast sample mainly consists of α-Mg matrix,Mg41Nd5 phase and Mg24Y5 particle. After solution treatment,the eutectic compounds completely dissolve into the matri. with a few cuboid-shaped particles remained. After subsequent ageing,a great number of dispersed β″and β′ precipitates distribute throughout the matrix,which strengthens the alloy,corresponding to mechanical properties as follows:σb=292 MPa,σ0.2=215 MPa andδ=4%. Besides,the strength of peak-aged sample decreases gradually with a gradual increase of ductility. The peak-aged sample exhibits cleavage fracture mode at room temperature,and the sample shows a quasi-cleavage fracture at 250℃.