ZHANG Zi-Cheng
,
ZHU Fu-xian LI Yan-mei
钢铁研究学报(英文版)
The effect of thermomechanical control processing (TMCP) on microstructure and mechanical properties of Fe-0.2C-1.44Si-1.32Mn hot-rolled TRIP steel was investigated by experiment. Strain-induced transformation and transformation-induced plasticity behavior of retained austenite was discussed. The results show that using multi-pass deformation, reduction per pass of more than critical deformation in austenite recrystallization region, total reduction of more than 58 pct in non-recrystallization region and in high temperature section of two-phase region can result in austenite being refined before γ → α transformation. It is beneficial to get refined ferrite grain in final microstructure. To obtain fine and uniform microstructure and excellent strength-ductility balance, a three-step cooling process (Laminar Cooling-Air Cooling-Ultra-Fast Cooling) after hot rolling was conducted. The ultimate tensile strength and elongation of the testing steel can reach 663 MPa and 41 pct respectively.
关键词:
hot rolled TRIP steel;TRIP effect;retained austenite;transformation-induced plasticity;mechanical properties
Journal of Materials Research
The morphology of the dark and bright regions observed by transmission electron microscopy for the Zr(64.13)Cu(15.75)Ni(10.12)Al(10) bulk metallic glass strongly depends on the ion beam parameters used for ion milling. This indicates that the ion beam could introduce surface fluctuation to metallic glasses during ion milling.
关键词:
room-temperature
程开甲
,
程漱玉
稀有金属材料与工程
应用Cheng-Born能带对称破缺理论和TFDC(Thomas-Fermi-Dirac-Cheng)电子理论研究了薄膜层内电子的特性.对金属铂上的TiO2膜层来说,TFDC理论指出电子(或空穴)将由金属与膜的间界面一侧迁移到另一侧.根据Cheng-Born对称破缺理论,当能带中只有很少的电子时,则只有极少的角区中存在电子,动量空间即产生对称破缺,从而导致超导电性,并由热力学估算出薄膜超导体的转变温度.结果显示薄膜超导体的转变温度至少比块材超导体的转变温度高一个量级.作者还设计了一个研究薄膜超导电性的实验.
关键词:
超导电性
,
薄膜
,
对称破缺
,
TFDC
李翔宇
,
赵霄龙
,
郭向勇
,
曹力强
材料导报
在Cheng-Vachon模型的基础上提出了一种针对由连续相和分散相组成的两相复合材料的新导热系数模型.通过引入一个新的参数,即分散相的修正体积含量来改进Cheng-Vachon模型不适用于分散相体积含量较大的缺点.使用新的导热系数模型预测泡沫混凝土的导热系数,与实验结果的对比表明,新的模型可以准确预测泡沫混凝土的导热系数.
关键词:
泡沫混凝土
,
复合材料
,
导热系数
,
无机材料