超磁致伸缩材料发展及其应用现状研究

概要地说明了磁致伸缩现象及其机理,回顾了磁致伸缩材料的发展。系统地介绍了国内外稀土铁系超磁致伸缩材料在各个领城的应用及其开发情况,剖析了基于该材料的各种应用器件原理与结构,并对其性能作了阐述。重点介绍了稀土铁系超磁致伸缩材料在机电工程中的应用,并对该材料未来的发展及应用领域作了展望。     

超磁致伸缩材料的工程应用研究现状

系统地介绍了国内外稀土超磁致伸缩材料在各工程领域中的应用及其开发概况,剖析了基于该材料的各种应用器件的原理与结构,并对其性能作了阐述。重点介绍了稀土铁系超磁致伸缩材料在机电工程中的应用,并对该材料未来的发展及应用领域作了展望。     

稀土超磁致伸缩功能薄膜材料的特性及应用研究进展

稀土超磁致伸缩功能薄膜是一种新型的功能材料，具有器件微型化、位移量大、非接触式驱动等性能，其优良的特性和广泛的应用前景在国际范围内得到普遍重视，已经成为超磁致伸缩材料研究的重点。本文介绍了稀土超磁致伸缩功能薄膜的特点，重点阐述了超磁致伸缩功能薄膜材料在流体控制系统、线性超声马达和微小行走机械等领域的研究成果及其应用，并对稀土超磁致伸缩功能薄膜材料在国内的发展前景进行了展望。     

磁致伸缩效应原理及在工业测量中的应用

简述了材料的磁致伸缩效应及逆效应原理,详细介绍了磁致伸缩纵向效应(焦耳效应)、扭转效应(维德曼效应)的工程应用及常用的磁致伸缩材料,重点介绍了这两种效应在工业测量领域中(如液位测量、固体材料的弹性模量测量、液体密度、黏度测量等)的应用.     

油罐计量技术的革命-超高精度磁致伸缩液位仪

介绍了磁致伸缩材料,详细描述了磁致伸缩液位仪的工作原理、技术特征及在液位测量中的应用和发展前景.     

超磁致伸缩材料在电液伺服阀中的应用现状

超磁致伸缩材料是一种具有响应速度快、磁致伸缩应变大、能量密度高等优良特性的新型功能材料,针对其研究和应用已经成为当前热点。基于现代工业对高性能电液伺服阀的需求,描述了该材料的磁致伸缩效应,并对其基本性能及物理效应作了阐述,同时通过对比压电陶瓷、形状记忆合金的性能参数,分析了超磁致伸缩材料的性能优势。最后着重介绍了该材料在喷嘴挡板阀、射流管阀及直接驱动式电液伺服阀当中的应用现状,并基于此现状对研制高性能的超磁致伸缩电液伺服阀关键技术进行了展望。     

电控喷油器用超磁致伸缩致动器发展现状

电控喷油器用致动器的性能,对喷油器喷油特性以及发动机工作性能具有重大影响。探讨了应用超磁致伸缩材料作为换能元件的超磁致伸缩致动器在电控喷油器中的应用现状。首先,介绍了超磁致伸缩致动器的发展背景;其次,简要介绍了超磁致伸缩材料的作用机理、优良特性以及超磁致伸缩致动器的结构原理;然后,将电控喷油器按照致动器通电工作方式、驱动方式的不同进行分类,系统梳理了超磁致伸缩致动器应用于电控喷油器的研究现状;最后,展望了电控喷油器用致动器的发展方向。     

超磁致伸缩材料在流体控制元件中的应用研究展望

本文介绍超磁致伸缩材料及其应用研究现状，重点提出该材料在流体器件方面可能的应用研究方向。     

稀土超磁致伸缩材料制备技术及应用研究

综述近年来有关稀土超磁致伸缩材料的研究进展,对稀土超磁致伸缩材料的制备技术、性能等作了详细介绍,并对其应用前景进行了展望。     

超磁致伸缩材料在液压阀中的应用现状

超磁致伸缩材料(GMM)具有应变大、响应快和输出力大等优良特性,它的应用开发已成为当前研究热点。该文介绍了超磁致伸缩材料的性能及物理效应;综述了该材料在机电领域的应用;系统地介绍了该材料在三类液压阀中的应用现状,并对该材料在液压阀中的应用作了展望。     

New Materials and their Machining

Sophistication in materials applications is the basis of technological progress and therefore there is a continuous search for new materials: i.e. materials that are light in weight, strong, tough, corrosion resistant, durable, wear resistant, resistant to various hazards of nature, safe for our health, etc. The new generation of materials with improved properties pose problems during machining because of their material structure, and hence they require new machining processes. The interactions between the tool and workpiece and also between the various micromechanisms involved in material removal during ductile regime machining of new materials, such as glasses, ceramics, and semiconductors, are discussed in this paper.     

先进制造技术与先进材料

从刀具材料、汽车材料和航空材料的发展说明先进材料对制造技术进步的作用；从结构材料的复合化及功能材料的多样化说明先进材料的诞生和应用离不开先进制造技术；指出材料制造技术的发展重点；强调重视传统材料的重要性。     

材料的切口强度与切口敏感性

较全面地总结了高塑性材料,低塑性材料和脆性材料拉伸切口强度的最新研究结果,给出了各种材料切口强度的估算公式。公式考虑了材料的拉伸性能,应力集中和切口根部的应力状态,以及加载条件等。     

Characterization and prediction of abrasive wear of powder composite materials

Composite materials produced by powder metallurgy provide a solution in many engineering applications where materials with high abrasion and erosion resistance are required. The actual wear behaviour of the material is associated with many external factors (particle size, velocity, angularity, etc.) and intrinsic material properties (hardness, toughness, Young modulus, etc.). Hardness and toughness properties of such tribomaterials are highly dependent from the content of reinforcing phase, its size and from the mechanical properties of the constituent phases. In this study an attempt is made to model the erosion wear behaviour of composite materials, to calculate the wear rate and to correlate erosion rates with experimental results and material parameters. Powder composites cermets and metal-matrix composite materials reinforced with different content of hard phase were used as examples in this research. Wear mechanisms of materials were investigated. Following from the main mechanisms of erosion wear the models of plastic deformation and brittle fracture are developed for prediction of erosion of powder composite materials. It was demonstrated, that the erosion rate of hardmetal-type materials can be predicted using the results obtained by microindentation methods. The use of hardness distribution parameters is justified with materials with low binder content.     

高浓度粘稠物料搅拌装置的研制与应用

针对高浓度粘稠物料内聚力较高,塑性和粘性较大,十分粘稠,搅拌均匀非常困难等问题,研发了专用的搅拌装置用于物料的存贮和搅拌成浆,实现了高浓度粘稠物料在仓内搅拌无死角、不堆积、不起拱、搅拌均匀且具有料位监测功能.本文详细介绍了该搅拌装置的主要结构、工作原理及主要特点.     

高导热T/R组件新型封装材料现状及发展方向

随着微电子技术的发展,T/R组件热流密度越来越大,封装材料也面临新的挑战,对新型高热导封装材料的需求变得愈加迫切.文章首先综述了传统T/R封装材料的优势及不足之处,同时指出了目前我国新型封装材料所存在的问题及进一步完善的措施,对金属基封装材料的发展趋势进行了展望,并提出了高导热T/R封装材料当前及未来的研究方向.     

Influence of the Erodent Shape on the Erosion Behavior of Ductile and Brittle Materials

Solid particle erosion is identified as a major wear process occurring in numerous industrial applications. A number of test parameters influence the behavior of the materials during this wear process. Particle shape is one of the key factors, which is often discussed for ductile or brittle materials in the literature, but a comparative study of ductile and brittle materials showing an effect of particle shape has not been addressed in detail until now. The present work discusses the influence of erodent shape on the wear behavior of a ductile (Ti-6Al-4 V alloy) and a brittle (TiN coating) material during the erosion process. Investigations are performed in an erosion test rig where the ductile and brittle materials are charged with spherical and angular SiO₂ particles at normal impact. Results show an inverse erosion behavior of ductile and brittle materials with the variation in particle shape. Ductile materials show low material removal with spherical particles, whereas brittle materials show low material removal rates with angular ones. This work also provides an analysis of the material removal phenomenon to understand the effect of particle shape on tested materials. Since materials removal phenomenon in ductile materials is often reported in the literature, this work addresses the material removal behavior especially in ceramic coatings.     

A review on the research of mechanical problems with different moduli in tension and compression

Most materials exhibit different tensile and compressive strains given the same stress applied in tension or compression. These materials are known as bimodular materials. An important model of bimodular materials is the criterion of positive-negative signs of principal stress proposed by Ambartsumyan. This model is mainly applicable to isotropic materials and deals with the principal stress state in a point. However, due to the inherent complexity of the constitutive relation, FEM based on iterative strategy and analytical methods based on a simplified mechanical model are required. In this paper, we review the basic assumptions of this model and its development, several innovative computational methods, and some important engineering applications. We also discuss the sequent key problems in this field.     

Unified Principal S-N Equation for Friction Stir Welding of 5083 and 6061 Aluminum Alloys

With the popularization of friction stir welding(FSW),5083-H321 and 6061-T6 aluminum alloy materials are widely used during the FSW process.In this study,the fatigue life of friction stir welding with two materials,i.e.,5083-H321 and 6061-T6 aluminum alloy,are studied.Fatigue tests were carried out on the base metal of these two materials as well as on the butt joints and overlapping FSW samples.The principle of the equivalent structural stress method is used to analyze the FSW test data of these two materials.The fatigue resistances of these two materials were com-pared and a unified principal S-N curve equation was fitted.Two key parameters of the unified principal S-N curve obtained by fitting,Cd is 4222.5,and h is 0.2693.A new method for an FSW fatigue life assessment was developed in this study and can be used to calculate the fatigue life of different welding forms with a single S-N curve.Two main fatigue tests of bending and tension were used to verify the unified principal S-N curve equation.The results show that the fatigue life calculated by the unified mean 50％master S-N curve parameters are the closest to the fatigue test results.The reliability,practicability,and generality of the master S-N curve fitting parameters were verified using the test data.The unified principal S-N curve acquired in this study can not only be used in aluminum alloy materials but can also be applied to other materials.     

现代刀具材料系列讲座（十一）超硬刀具材料—金则石与立方氮化硼

介绍了超硬刀具材料（金刚石与立方氮化硼）在加工不同工件材料时的切削数据。工件材料包括各种难加工材料与有色金属。文中列出较多的试验数据和曲线,阐述了超硬刀具的切削性能和切削机理。