Q.B. Yang
,
G.J Shifietand E.A. Starke
,
Jr(Department of Physics
,
Xiangtan University
,
Xiangtan 411105
,
China)(Depedment of Materials Science and Engineering
,
University of Virginia
,
Charlottesvil1e
,
VA22903
,
USA)
金属学报(英文版)
A clear understanding of the structure of the S precipitates which are present in Al-Li-X alloys is verp imporiant because the S -phase decreases the localization of strainand promotes less anisotropic properties during deformation. The close structural re-lationship between the S-phase and the Al matrix and their possible intedece bound-ary strvcture are described in detail. The proposed model is in good agreement with::::rimental obserwations. The dynamics Of the phase trunWrmation and possiblermation mechani8ms for the S,-phase are alSo proposed.
关键词:
Al-Li alloy
,
null
,
null
焦安杰
物理测试
应用显微组织观察,低倍酸蚀,电镜扫描等手段,通过宏观与微观的裂纹对比,分析S355JR带钢表面边缘裂纹主要为板坯角裂引起;指出形成S355JR板坯角裂的主要影响因素,并提出了有效避免措施.
关键词:
S355JR带钢
,
表面裂纹
,
分析
,
角裂
QIAO Lijie LIU Rui XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China
金属学报(英文版)
The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.
关键词:
stress corrosion cracking
,
null
,
null
,
null
景财良
,
刘延强
,
宋佳友
,
王胜东
,
彭国仲
中国冶金
doi:10.13228/j.boyuan.issn1006-9356.20150155
针对国内某厂在轧制厚规格S275JR钢卷过程中在钢卷中心位置附近出现了大量裂纹缺陷问题,通过对该缺陷宏观形貌、化学成分、金相组织等进行研究分析后,确定了板卷表面裂纹缺陷是由钢坯皮下微裂纹造成的.基于此分析对S275JR生产过程中的硫质量分数、过热度、结晶器冷却强度与保护渣进行了优化.工业实践表明,工艺调整后钢卷表面裂纹缺陷由12％降低到0.93％.
关键词:
厚规格
,
表面裂纹
,
钢卷
,
皮下微裂纹
Douxing LI and Hengqiang YE (Laboratory of Atomic imaging of Solids
,
Institute of Metal Research
,
Chinese Academy of Sciences
,
Shenyang
,
110015
,
China)
材料科学技术（英文）
The present paper summarizes the current status of high resolution electron microscopy (HREM)and the applications of HREM to materials science and condensed matter physics. This review recounts the latest development of high resolution electron microscope, progress of HREM and the applications of HREM, including the crystal structure determination of microcrystalline materials and characterization of the local structure of the defects and nanostructured materials as well as qualitative and quantitative analysis of the grain boundaries, interfaces and interfacial reactions in the advanced materials by means of HREM in combination with electron diffraction,subnanometer level analysis, image simulation and image processing.
关键词:
