Nanostructured coatings and nanomodified materials

Abstract

The research, development and application of nanostructured coatings and nanomodified materials are briefly introduced, including thermal sprayed ceramic and self-lubricating coatings, electroplated and electrophoresis deposited coatings, nanomodified hard metals and alloy cast irons. On the basis of these examples, it is believed that the industrial application of nanotechnology is not just a dream but becoming a reality.     

Spark plasma sintering for multi-scale surface engineering of materials

Recently, significant progress has been made in understanding the effect of multi-scale microstructural features, including nano-, micro-, and macro-features, on the properties of materials. Controlling the length scale of micro-structural features provides tremendous opportunities for enhancing the properties of materials, including extraordinary strength and hardness, unprecedented damage from tribological contacts, and improvements in a number of functional properties of the materials. Spark plasma sintering (SPS) process which combines the effects of uniaxial pressure and pulsed direct current is becoming increasingly important for the processing of bulk shapes of amorphous and nanostructured materials. These materials can also be good candidates for high-performance coatings. This article presents a review of our ongoing efforts to use SPS to produce engineered coatings of amorphous and nanostructured materials for various applications, including structural, tribological, and biomedical applications.     

Nanostructured ceramic and hybrid materials via electrodeposition

Electrodeposition is unique in that it can be used for processing metals, ceramics, and polymers. Electrochemical strategies offer important advantages and unique possibilities in the development of nanomaterials and nanostructures. Novel electrodeposition methods have evolved into an important branch of nanotechnology. This paper presents a brief overview of recent developments in the application of electrochemical methods for synthesis of nanostructured ceramic and hybrid materials.     

Nanostructured materials: basic concepts and microstructure

Nanostructured Materials (NsM) are materials with a microstructure the characteristic length scale of which is on the order of a few (typically 1–10) nanometers. NsM may be in or far away from thermodynamic equilibrium. NsM synthesized by supramolecular chemistry are examples of NsM in thermodynamic equilibrium. NsM consisting of nanometer-sized crystallites (e.g. of Au or NaCl) with different crystallographic orientations and/or chemical compositions are far away from thermodynamic equilibrium. The properties of NsM deviate from those of single crystals (or coarse-grained polycrystals) and/or glasses with the same average chemical composition. This deviation results from the reduced size and/or dimensionality of the nanometer-sized crystallites as well as from the numerous interfaces between adjacent crystallites. An attempt is made to summarize the basic physical concepts and the microstructural features of equilibrium and non-equilibrium NsM.     

A virtuous cycle in materials engineering and surface finishing: design-print-image

ABSTRACT

Electrochemical cells continue to be important in the synthesis and processing of commodity and speciality chemicals, environmental remediation, energy conversion and electrodeposition. A current challenge is an increasing need to achieve a high performance from cells which can be easily designed, manufactured or modified. Conventional manufacturing has involved machining of cast and extruded materials in a mechanical engineering workshop, which can involve delays, the need for skilled specialists and considerable costs. Increasingly, the benefits of fast prototyping as a route to manufacture are being realised. Modern approaches to detailed imaging of structures (e.g. by computed tomography) can be combined with on-screen, digital design (via computer software suites), followed by modification then data export to a 3D printer. In this fashion, a fast, flexible, cost effective and attractive route to manufacture of prototype electrodes and cell bodies can be realised. This review paper demonstrates the success of a design-image-manufacture cycle to realise polymeric electrochemical flow cell compartments and electrodes. Future developments are suggested, with 3D printing likely to offer creative solutions in many surface finishing applications.     

雷廷权院士对材料热处理及表面工程的贡献

尊敬的恩师雷廷权院士离开我们已经一年多了,他的音容笑貌经常浮现在我们的脑际,他的高尚品格一直感动着我们的心灵,他的坚毅精神不断激励着我们的求索.恩师学识渊博、治学严谨、勤于钻研、勇于创新、精湛学术、高山仰止、诲人不倦、德高望重,他是我们的良师益友,他是我们的楷模典范,他是我们最尊敬的师长.有幸成为他的学生是我们今生的莫大荣幸,他的教诲让我们受益终生,我们永远怀念他.     

再制造工程与自动化表面工程技术

进入新世纪后,我国的再制造工程发展迅速,以国务院文件、国家法规等形式对再制造的地位予以肯定.再制造是废旧产品高技术修复、改造的产业,是维修工程和表面工程的高级阶段.表面工程的基本特征是综合、交叉、复合、优化,研究对象是材料的"表面".纳米表面工程是纳米材料与传统表面工程技术的集成创新.为了适应再制造批量化生产特点的要求,开发了以自动化纳米电刷镀表面技术、智能化自修复表面技术为代表的5类自动化和智能化表面工程新技术,适应了表面工程的发展方向和再制造工程的实践需要.     

Materials science and materials engineering

When materials are viewed from the vantage point of how they are processed and used rather than from the science that underlies and explains their behavior, it is difficult to differentiate problems associated with different classes of materials; hence, the trend toward materials scientists and engineers.     

A program in materials engineering

Majors in chemical, metallurgical, and materials engineering are offered by a unified department at the University of Michigan.     

Design education in metallurgical and materials engineering

In general, the attendance level and interest in the discussions that took place following the presentations at each of the four sessions of the symposium suggest that educational programming at future TMS meetings has a very solid constituency. The organization of the symposium Powder Processing Education for the Year 2000 by the Materials Design & Manufacturing Division’s Powder Metallurgy Committee for the 1994 TMS Annual Meeting is likely to provide further demonstration of this level of interest. As our profession continues to evolve, TMS has the opportunity to play a signal role as a conduit of information among professionals and educators wishing to improve their “product” and between educators wishing to share with others the best means of obtaining such improvement.     

Triple lines in materials science and engineering

We assess the impact of triple lines in materials preparation and use by considering several examples of materials behavior in which they have identifiable effects. The microstructural roles of triple lines are also considered and some persistent scientific questions are raised.     

Aqueous processing in materials science and engineering

Reviews of aqueous processing in JOM have traditionally focused on hydrometallurgical process routes. This article, however, addresses the application of aqueous processing in materials engineering and presents some promising developments that employ aqueous-based routes for the manufacture of high-tech components and specialty products. Such applications include producing metallic and ceramic powders; etching; surface modification by electroplating and electroless plating; manufacturing jewelry and intricate components by electroforming; and producing advanced ceramics, composites, and nanophase materials by sol-gel and biomimetic processing.     

表面工程技术的发展与应用

表面工程技术是20世纪80年代世界十项关键技术之一。突出特点在于无需整体改变材质而获得原基体所不具备的某些特殊性能,在科研、生产中得到了广泛应用,取得了良好的经济效益,简要概述了热喷涂技术、激光表面工程技术、堆焊表面工程技术及其它表面工程技术的特点、应用范围、研究现状和发展中存在的问题。