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电镜观察了过载前后的裂纹和断口形貌. 图1 AZ31镁合金的显微组织 Fig.1 Microstructure of AZ31 Mg alloy 2 结果与讨论 2.1 不同方向的拉伸性能 图2所示为AZ31镁合金平行(z-x)和垂直(x-z)于长度方向的拉伸曲线.由图2可看出,两个方向上抗拉强度相当,但屈服强度存在明显的差异.x-z方...应力,因此孪生变形时会引起载荷的波动.此外,对拉伸前后AZ31镁合金显微组织的对比研究也证实了这一点,拉伸前并未观察到孪晶组织的存在,拉伸后有大量的孪晶存在,说明孪生是镁合金单向载荷下的主要变形方式之一. 图2 AZ31镁合金不同方向的拉伸曲线 Fig.2 Tensile curves in various directions of AZ31 Mg alloy......
Mg-10Gd-3Y-0.4Zr alloy was investigated. It was found that the nucleation undercooling of the α-Mg phase increased from 2.3 to 6.3 °C. The average α-Mg grain size increased from 44 to 71 μm, but then decreased... the dimple-like fracture, with the micro-porosity and the re-oxidation inclusion as major defects. The average α-Mg grain size played a main role in the YS of sand-cast Mg-10Gd-3Y-0.4Zr alloy, besides other......
, which is consistent with the simulated results by the proposed model. Key words: Mg alloy; deformation mechanism; polycrystal plasticity model; texture 1 Introduction Mg and its alloys usually show..., an AZ31 Mg alloy was subjected to an equal channel angular pressing (ECAP) and its elongation-to- failure was enhanced to above 40% [4]. Therefore, the ductility of Mg alloy at room temperature can......
Mg处理高钢级管线钢焊接热影响区晶内铁素体形核机制研究赵辉1,胡水平2,武会宾3,李太全4,安航航4(1.北京市北京科技大学高效轧制国家工程技术研究中心2.北京科技大学 高效轧制国家工程研究中心,北京 1000833.北京科技大学 高效轧制国家工程研究中心4.北京科技大学 冶金与生态工程学院,北京 100083)摘 要:采用热模拟技术,EBSD技术和透射电子显微镜对镁处理高钢级管线钢的焊接热影响区(HAZ)晶内铁素体(IGF)的形核现象和机制进行了试验研究.结果表明:镁处理钢中形成大量的Al,Ti,Mg复合氧化物夹杂,其颗粒大小为0.5~3μm.在粗晶热影响区(CGHAZ)中,含Mg复合氧化物具有促进晶内针状铁素体形核的能力.对Mg处理高钢级管线钢焊接热影响区晶内铁素体的形核机制进行了探讨.
; 文献标识码:A Closing and repairing process of Mg alloy casting imperfections in plastic deformation CAO Han-xue1, 2, LONG Si-yuan1, 2, YOU Guo-qiang1, 2, LIAO Hui-min1 (1. College...: The effects of press deformation on the morphologies evolution of Mg alloy casting imperfections (shrinkage porosity and cavity) and the stress distribution around the casting imperfections were observed......
Mg-rare earth (RE) alloy by selective laser melting (SLM) process, the microstructure and mechanical properties of Mg-15Gd-1Zn-0.4Zr (wt.%) (GZ151K) alloy were investigated. The results show that fine grains (~2 μm), fine secondary phases and weak texture, were observed in the as-fabricated (SLMed) GZ151K Mg alloy. At room temperature, the SLMed GZ151K alloy has a yield strength (YS) of 345 MPa......
aging treatment, the corrosion modes of Mg–0.25Y and Mg–(2.5, 5, 8 and 15) Y alloys were uniform corrosion and pitting corrosion with small local deep corrosion. Key words: Mg–Y alloy; aging treatment... solubility in Mg alloy, and the solid solubility will decrease drastically with the reduction of temperature, so the heavy rare earths has a very good solution and precipitation strengthening effect......
isothermal heat-treatment-die-pressure-casting process were studied. It is found that there are three main phases formed in the experimental alloy, i.e., α(Mg), (α(Mg)+Al2Ca) eutectic and Mg17Al12. When the alloy modified by Sr is heat-treated at 585℃, the primary α(Mg) phase divorces into lumps. Then the lumps evolve into spheroids gradually with isothermal time increasing. After treated for 25min......
mechanism of Mg alloy under the environment containing halogens. 2 Computational We applied first-principles methods based on the density functional theory (DFT) implemented in CASTEP (Cambridge sequential... that MgF2 protective film is easier to form and more stable than MgCl2 on Mg surface, and further the corrosion velocity of Mg alloy in F-containing solution is smaller than that in Cl-containing solution......
