面向RF IC的片上铁氧体磁膜电感

采用集成工艺制作了片上铁氧体磁膜(Ni0.4Zn0.4Cu0.2Fe2O4,Y2.8Bi0.2Fe5O12和Co7ZrO9)射频微电感.铁氧体薄膜采用溶胶凝胶法制作,高频特性较好,适于片上电感的应用.对电感样品进行了测试和等效电路分析,结果表明,与无磁膜结构相对比,铁氧体磁膜电感显著增强了电感性能,是一种实现小尺寸、高性能片上RF IC电感的很有前景的途径.     

宽带集中元件环行器计算机辅助设计

本文从散射矩阵本征值的频率关系出发,对宽带集中元件环行器所需的设计参数作了优化计算。文中采用乘子法将约束优化问题化为无约束优化问题。计算结果与实验结果较一致并证实了为得到宽带性能实验中出现的隔离双峰的现象。     

卷取温度和卷取后冷速对Nb-V-Ti微合金钢组织的影响

通过Gleeble-3800热模拟试验机对Nb-V-Ti微合金钢进行了不同卷取温度和卷取后冷却速度的热模拟试验,并且对所获得的组织进行了观察与分析。两阶段轧制后,试验钢在540~460℃卷取以及卷取后冷速为2~0.5℃/s的条件下,最终组织为针状铁素体、少量多边形铁素体和M/A组元。研究结果表明,随着卷取温度的降低,组织逐渐细化,这与较低的卷取温度导致过冷奥氏体在中温转变区间具有较低的转变温度有关。同时加快卷取后的冷却速度,组织进一步细化,这可能与卷取后发生一定程度的回复有关。     

Improvement of the magnetoelectric response in NiFe2O4−Sr0.5Ba0.5Nb2O6 composites using LiNbO3 as sintering additive

Magnetoelectric (NiFe₂O₄)_0.3−(Sr_0.5Ba_0.5Nb₂O₆)_0.7 composites with addition of LiNbO₃ as sintering additive were prepared by a classical mixed-oxide method. XRD patterns of ceramics sintered between 1000 and 1200 °C show the desired Sr_0.5Ba_0.5Nb₂O₆ and NiFe₂O₄ phases. SEM investigations confirm the 0–3 connectivity of the composite ceramics. The addition of 10 and 20 mol% LiNbO₃ improves the densification of the composite ceramics and leads to an increase of the size of the Sr_0.5Ba_0.5Nb₂O₆ grains. Magnetic measurements show hystereses with low coercivities. Dielectric measurements were carried out depending on temperature and frequency. The samples with the LiNbO₃ addition show significantly higher resistivity values (σ_DC). Magnetoelectric measurements were carried out in dependence of the magnetic DC-field, temperature, and frequency. The maximum magnetoelectric coefficient (α_ME) rises with the addition of LiNbO₃ from 180 to 803 µV Oe⁻¹ cm⁻¹ (@900 Hz). Temperature dependent measurements show a continuously decreasing of α_ME with lower temperature.     

铁氧体变极化效应最佳磁化场的研究

本文将耦合波理论和变分原理用于探求铁氧体变极化效应的最佳磁化场,并用计算机进行了数值计算,画出了几种情况的最佳磁力线形状,理论计算与实验结果基本相符。     

Microstructural development in a low carbon Ti-microalloyed steel during deformation within the ferrite region

Microstructural evolution of ferrite in a low carbon Ti-microalloyed steel, during deformation within the ferrite region, was investigated by using torsion testing. Warm deformation characteristics of ferrite were studied by analyzing of its flow curves, optical microstructures and electron back-scattered diffraction maps. The results show that an unstable sub-boundaries network forms and then these transform into high angle boundaries, with further straining. It was found that the occurrence of continuous dynamic recrystallization is responsible for the development of very fine ferrite grains with high angle boundaries.     

应力腐蚀环境下超级双相不锈钢换热管U形弯管技术研究

介绍了典型超级双相不锈钢S32750的特性,包括化学成分、力学性能和耐腐蚀性能等;对于应力腐蚀环境下国产超级双相不锈钢换热管U形弯管的局部热处理工艺进行了研究;通过采用点计数法定量测定弯管的铁素体含量、并对弯管进行一系列腐蚀试验,验证了U形弯管工艺的合理性,形成了一套完整的弯管工艺。     

Determining phase volume fraction in steels by electron backscattered diffraction

The relative sharpness of electron backscattered diffraction (EBSD) patterns is used to quantify the volume fraction of ferrite in low-carbon steels. EBSD pattern quality (PQ) maps are shown to improve imaging of martensite and ferrite over optical and secondary electron imaging. Ferrite volume fraction in isothermally reacted Fe–0.12C–3.28Ni are quantified using PQ maps by manual point counting and image thresholding.     

Y形铁氧体波导锁式开关设计

本文用保角变换和变分法相结合,算出Y形退磁铁氧体结的谐振频率,还算出开关各部分的阻抗变化。这些计算都为x,Ka波段的开关所证实。