A 2D approximation of standard electrical steel losses and permeability

A first design approach for an electrical machine need not be done with the efforts of detailed magnetic field considerations. Often a more pragmatic way already fulfills the desired accuracy. Performing fast by hand calculations depends on the data that is available; for e.g., the lamination geometry or material. This article provides a table for different electrical steels that can be used in the analytical calculation of magnetic circuits. In comparison with existing publications this article shows two-dimensional functions for the specific iron losses and the relative permeability. Both magnetic flux density and frequency are input variables.     

卷取温度对无取向电工钢电磁性能和板形的影响

电磁性能和板形是无取向电工钢的重要产品特性,卷取温度作为生产控制中一个重要的工艺参数,对它们有重要影响。本研究通过大生产实验,发现高温卷取、U形卷取的层流冷却方式可以有效促进晶粒长大和均匀热轧带钢组织,并进一步提高无取向电工钢的电磁性能,但是会增大带钢纵向厚度的波动,对带钢横向厚度的控制无显著影响。     

50A1300牌号无取向硅钢磁性能改善工业实践

结合工业化生产的50A1300牌号无取向硅钢,分析了化学成分、RH精炼脱氧方式、板坯装炉温度以及热轧平整工艺等对磁性能的影响,探讨成品钢磁性能的改善。结果表明,采取改善后,50A1300牌号无取向硅钢的磁性能得到明显改善。2012年,该钢种平均铁损、磁感应强度分别达到5.26 W/kg、1.762 T,能够较好地满足用户市场需求及同行对标需要。     

层压方法对功率型LTCF变压器结构及性能的影响

采用双层硅胶加盖不锈钢材质层压板的层压方法制备功率型低温共烧铁氧体(LTCF)变压器。通过断面显微结构、电感值及耐压的测试,研究了层压方法对其结构及性能的影响。结果表明,相对于传统的层压方法,新方法制作的变压器层压受力均匀、表面不平整度≤±5μm/10 mm,无凸起、分层,排胶烧结过程中未出现开裂、翘曲等缺陷,显微结构理想。变压器性能为,初级电感:≥60μH、次级电感:≥2.6 m H、漏感:≤35μH、耐压:≥1500V(DC),且满足高低温应用环境(-55~+85℃)下磁性能使用可靠性和环境适应性要求。     

注射成形Fe-50%Ni软磁合金的微观结构与性能

Fe—50％Ni合金是一种典型的高磁导率和低矫顽力软磁材料，有着广阔的应用前景。本实验采用注射成形方法制取Fe—50％Ni生坯，研究了烧结工艺对最终产品性能及微观组织的影响，并分析了影响产品磁性能的一些主要因素。实验表明烧结温度的提高和烧结时间的延长能够较好改善产品的力学性能；密度是影响产品磁性能的主要因素，杂质(主要为C、O、N)的含量和晶粒尺寸对刺磁、最大磁导率和矫顽力也有较大的影响；通过注射成形方法制取的Fe—50％Ni，其性能要优于采用粉末冶金方法制造的Fe-50％Ni。     

0.10mm与0.23mm取向硅钢在不同运行工况下磁特性的测量与对比分析

在电力电子装备的复杂运行工况下,不同类型取向硅钢表现出的磁特性不同.为了使设计人员在面对不同电力电子装备运行工况时,能够快速准确地对不同类型取向硅钢进行选型,基于中频爱泼斯坦方圈测量装置实现了不同运行工况下0.10 mm超薄取向硅钢与0.23 mm普通厚度取向硅钢磁特性的测量,揭示了两种不同类型取向硅钢的磁特性变化规律...     

Provision of thermal engineering with structural materials—Basis of its safe operation and development

The role of thermal engineering (among other sources) in power supply is represented and its main advantages are described. It is shown that increasing the efficiency of thermal engineering as a result of an increase of the energy carrier’s parameters was provided by creating new materials with improved service properties. While developing the technology of ultra-supercritical parameters new construction steels with the temperature of application up to 640°C have been developed and utilized in Russia. Perspective development of thermal engineering provides attainment of ultra-supercritical parameters (720–740°C), which can be implemented by application of a new class of construction materials—nickel-based ultra heat-resistant alloys.     

Reluctance motor with strong rotor anisotropy

A new rotor design for the synchronous reluctance motor is presented. It has something in common with the segmented and axially laminated rotors that have been developed in the past. The new rotor achieves strong anisotropy by interleaving magnetic iron lamination with nonmagnetic spacers of approximately equal thickness. It is shown that the magnetizing inductance is very much lower in the quadrature than the direct axis and that this rotor has the potential to develop more torque than earlier machines. Laboratory results are presented, and the machine is compared with an induction motor in the same frame     

New heat-resistant chromium steels for a promising objects of power engineering

Data are presented on new-grade 12Kh10M1V1FBR and 10Kh9V2MFBR heat-resistant chromium steels for turbine rotors, boiler tube systems, and pipelines of ultrasupercritical steam parameters. The operating properties of new steels are assessed in comparison with those of 12Kh1MF, 15Kh1M1F, and 10Kh9MFB steels.     

Numerical modelling of anisotropy and eddy current effects in ferromagnetic laminations using a co‐energy formulation

The paper deals with a numerical model for the evaluation of electromagnetic fields in one steel lamination under the influence of a rotating magnetic flux, taking into account anisotropy effects. For this purpose a detailed material model, described by a differential permeability tensor, is included in the macroscopic electromagnetic field calculations in one lamination. Here, by geometrical and physical considerations, the governing Maxwell equations are reduced to a system of parabolic PDEs for the components of the magnetic field vector, under appropriate boundary and initial conditions. We present a suitable numerical approximation based upon a finite element–finite difference method, which properly takes into account the material characteristics. The study leads to a more realistic numerical modelling of the electromagnetic phenomena inside electric and magnetic conducting laminations due to anisotropy effects. Numerical results are compared with those from simplified analytical formulae. Copyright © 2001 John Wiley & Sons, Ltd.     

Using utility demand-side management programs to spur thedevelopment of more efficient appliances

Traditionally electric and gas utilities have promoted the development of more efficient appliances through research institute R&D programs and through utility incentive programs which provide incentives for efficient commercialized products. A third mechanism has evolved: multiutility incentive programs which target higher levels of efficiency than the best products on the market. One program of this type is now underway for refrigerator/freezers. A second program has just begun for residential clothes washers. Further efforts are likely as evidenced by a research project which identified major opportunities for more efficient appliances and by the formation of a new organization to develop and promote programs of this type. This paper summarizes each of these efforts     

一种新型铁素体耐热钢

针对一种w(Cr)=15%(简称15%Cr)的新型铁素体耐热钢展开文献调研和分析,摸清该新型铁素体耐热钢的的设计思路、强化机理、组织性能和研究现状。结果表明:15%Cr铁素体耐热钢具有较好的组织稳定性,比传统的w(Cr)=9%~12%的铁素体钢具有更优的持久强度和抗蒸汽氧化性能,有很大潜力成为用于650℃超超临界火电机组高温部件的候选钢种。     

钢的气蚀抗力与力学性能的相关性

本文在对四种材料多种热处理工艺条件下的气蚀模拟试验的基础上，提出了一个用钢的静拉伸和示波冲击试验所测试的机械性能而构成的复合力学参量评定其气蚀失重率的数学函数。并经实验证明，钢的气蚀抗力除取决于其自身的力学性能外，还应考虑钢的热稳定性及物理化学性能。     

SiC基稀磁半导体材料的研究进展

稀磁半导体材料(DMS)是一种新型的磁性半导体材料,它同时利用了电子的电荷和自旋属性,兼有铁磁性能和半导体性能,在自旋电子器件领域有着重要的研究价值。主要介绍了DMS的发展过程,总结了最近几年SiC基稀磁半导体材料的研究进展,包括制备方法、性质研究和存在的主要问题,并展望了今后的研究方向。     

Investigation of Creep Processes and Microdamages in 10Kh9V2MFBR-Sh High-Chromium Steel

During the modernization and the new construction of power units at TPPs in Russia, high-chromium martensitic steels with higher heat-resistant properties than the traditional perlite steels are increasingly used as structural materials. High-chromium steels have a necessary regulatory support for their use in domestic power engineering. However, up to the present time, the issue of assessing the quality of these steels at the analysis of their state during long-term operation remains open. The article proposed is one of the first attempts to create a system of quality criteria for martensitic steels based on their microdamage parameters. Tests were carried out on the long-term strength and creep of samples from 10Kh9V2MFBR-Sh steel at high temperatures with the construction of creep curves in relative coordinates “deformation related to the deformation of fracture, current time related to time to failure.” For some samples, the tests were interrupted and the metal was subjected to metallographic studies consisting of the analysis of microdamage with reference to the accumulated creep strain. It has been shown experimentally that the deformation curve of high-chromium steel differs from the analogous curve of pearlitic steel by a longer and flat section of steady creep and by a sharper transition to the third accelerated creep stage, which has a very short time period (approximately 10% of the total durability). The tendency to the increase in the microdamage of the structure of steel as the accumulated creep strain increases with time was confirmed. The beginning of transition to the final creep phase is characterized by the formation of contours of future pore chains and by the appearance of individual large pores of up to 6 μm in size, the presence of which in the microstructure of the martensitic steel indicates a very significant accumulation of creep strain, and corresponds to the predestruction stage of metal. It is necessary to continue the research to obtain quantitative indicators on the accumulation of microdamage in high-chromium steel in a conjunction with the development of a metal resource under creep conditions.     

超超临界火电机组材料研究及选材分析

由于蒸汽温度和压力的提高对火电机组关键部件的抗蠕变、疲劳、高温氧化与腐蚀等性能都提出了更苛刻的要求，耐热材料的开发及其应用是发展超超临界发电技术的最重要的基础。通过对国际上各阶段的材料研究计划介绍以及对超超临界机组中各关键部件采用的耐热材料发展的论述，归纳和总结了现阶段超超临界火力发电机组所采用的几种典型新型耐热钢的性能，并根据机组的不同参数对锅炉部件材料的选择进行了分析和讨沦。     

Study of the structure and properties of metal of the major steam lines of a CCGT-420 unit made from high-chromium Х10CrMoVNb9-1 (P91) steel

The technology of manufacture of live steam lines and hot reheat lines at FINOW Rohrsysteme GmbH are discussed. These pipelines are designed for high-performance CCGT units and are made from high-chromium martensitic steel X10CrMoVNb9-1 (P91). The principles of certification and evaluation of conformance of thermal and mechanical equipment made from new construction materials with the TRCU 032-2013 technical regulation of the Customs Union are detailed. The requirements outlined in Russian and international regulatory documents regarding the manufacture of pipes and semifinished products for pipeline systems are compared. The characteristic features of high-chromium martensitic steel, which define the requirements for its heat treatment and welding, are outlined. The methodology and the results of a comprehensive analysis of metal of pipes, fittings, and weld joints of steam lines are presented. It is demonstrated that the short-term mechanical properties of metal (P91 steel) of pipes, bends, and weld joints meet the requirements of European standards and Russian technical specifications. The experimental data on long-term strength of metal of pipes from a live steam line virtually match the corresponding reference curve from the European standard, while certain experimental points for metal of bends of this steam line and metal of pipes and bends from a hot reheat line lie below the reference curve, but they definitely stay within the qualifying (20%) interval of the scatter band. The presence of a weakened layer in the heat-affected zone of weld joints of steel P91 is established. It is shown that the properties of this zone govern the short-term and long-term strength of weld joints in general. The results of synthesis and analysis of research data support the notion that the certification testing of steam lines and other equipment made from chromium steels should necessarily involve the determination of long-term strength parameters.     

水基Fe3O4磁流体动态法拉第磁光特性的研究

为研究在交变磁场作用下铁磁流体动态法拉第磁光特性,设计了一套用于研究铁磁流体磁光效应的实验平台,分析研究了交变磁场作用下所含Fe3O4颗粒的质量分数分别为2%、5%、10%、15%、20%、31.2%等质量分数的水基Fe3O4磁流体动态法拉第磁光特性。实验结果表明:铁磁流体对工频交变磁场的响应线性度达到0.9946;与块状玻璃磁光介质相比,铁磁流体所展示的法拉第磁光特性有很大差异;质量分数对铁磁流体法拉第磁光特性的影响明显,其趋势是先随着铁磁流体质量分数的降低,其对磁场的响应程度反而缓慢增强,到质量分数为10%时达到最大值,其后随着质量分数的降低而急剧减弱。分析表明:铁磁流体的这种磁光特性与其在磁场作用下形成平行于磁场方向的线状链有密切关系;质量分数对铁磁流体法拉第磁光特性的影响主要是因其黏度变化导致。     

锰含量对无取向电工钢组织性能的影响

研究了锰含量对w（Si）=1．8％Si无取向电工钢组织和性能的影响。结果表明,钢中锰含量从0．3％增加到1．2％时,由于α-γ相变的产生,铸坯低倍组织、热轧板金相组织及成品织构等均发生了不同程度的变化,对成品表面质量及磁性能产生了明显的影响。     

磁性纳米粒子的制备及应用

概述了国内外磁性纳米粒子的研究近况.介绍了具有广泛应用前景的磁性纳米粒子的常用制备方法,以及粒子不同于常规材料的独特效应及优异的磁学性能,并结合其特性介绍了这一新材料在磁记录材料、磁性液体、生物医学、传感器、催化、永磁材料、颜料、雷达波吸波材料以及其他领域的应用.