汽轮机叶片的激光合金化与激光淬火

对调质态2Cr13低碳马氏体不锈钢汽轮机叶片,采用7 kW的CO2横流激光器分别进行激光合金化和激光淬火,考察其显微组织和力学性能.结果显示:激光处理后,在表面硬度方面,激光淬火提高了110%倍左右,激光合金化提高了180%左右;在残余应力分布上,激光淬火增加了表面的残余压应力,激光合金化将使残余压应力转变为残余拉应力.在综合性能上,激光合金化具有更高的优势,在叶片强化上具有更好的发展前景.     

柴油机气缸套表面强化工艺及磨损试验的研究

论述了柴油机气缸套表面强化处理问题,包括盐浴氮化强化、激光淬火强化、珩磨处理等;分析了相关的金相、硬度问题;还介绍了磨损试验和装车考核结果及结论性意见。     

激光淬火吸光层技术的发展及在内燃机工业中的应用评述

综述了激光淬火及吸光层技术在国内外的应用和发展过程。比较了不同吸光层的性能特点，介绍了新型吸光层技术在内燃机激光淬火中的应用及发展趋势。     

内燃机气缸套内表面淬火方法探究

本文简单阐述了激光淬火、等离子淬火、高频淬火等几种气缸套内表面淬火处理方法的原理,分析了它们各自的特点.     

40／45柴油机活塞顶环槽的激光淬火研究

对４０／４５柴油机活塞顶环槽表面进行了激光淬火并研究了淬火层的组织，硬度分布和耐磨性能。经激光淬火的活塞顶环槽，表面硬度达７５０ＨＶ，硬化层深度为０．５５ｍｍ，，耐磨性比原高频淬火工艺提高了１．３倍。实际运行结果表明，激光淬火是提高大型柴油机活塞顶使用寿命的有效途径。     

汽轮机末级叶片进汽边表面防水蚀工艺研究

对比分析了汽轮机末级叶片进汽边的激光熔覆、激光淬火、钎焊司太立合金片表面防水蚀技术的工艺性。分别从工艺的实现能力以及防水蚀处理后叶片的工艺性能,如无损检测、缺陷分布、变形情况、组织与硬度等方面进行综合评估。结果表明,现有应用的几类表面防水蚀技术有着基本一致的变形趋势,防水蚀处理后表面硬度均在400HV以上。在缺陷的工艺控制、表面成型、界面结合及防水蚀性能方面,激光熔覆、激光淬火优于钎焊,但生产效率较低。激光熔覆工艺表现出较好的综合性能,是汽轮机末级叶片防水蚀技术的一个发展方向。     

活塞缸套副激光强化试验研究

简要介绍了激光表面强化技术及其机理,利用激光技术对大功率机车柴油机的气缸套、活塞环槽进行激光硬化处理技术的试验研究,经硬化处理的气缸套、活塞已装车试验考核.     

激光淬火

激光淬火激光具有许多宝贵的特性：亮度高、单色性和方向性强，在许多方面有广泛应用。以高能量激光为能源，以极快速度加热工件并自冷硬化的淬火工艺，称之为激光淬火。激光淬火具有许多独特之处：加热速度快、质量好、效率高、变形极微小、控制方便，可以应用于许多方面...     

海外文献速递

WZ００２８８８精密高频淬火———《工业加热》，２００１，Vol３８，No．６，１３～２１（日）概述了高频淬火技术的发展现状。打破传统的高频淬火观念，以全新的高频淬火理论阐述了高频淬火的本质、品质与特点。介绍了提高工件淬火品质特性的强化淬火技术与精密淬火新技术。简述了日本富士电子工业株式会社实施最佳高频淬火所采取的种种措施。照５图８表１参１犤陈留根摘犦WZ００２８８９节能型感应加热用振荡电源———《ELECTRO－HEAT》，２００１，No．１１５，１９～２４（日）近年来，电力电子技术发展迅速，高输出、高频率…     

解析两项新的内燃机气缸套标准

本文介绍了新发布实施的JB／T5083—2005《内燃机干式铸铁气缸套技术条件》和JB／T10406—2004《内燃机激光淬火气缸套技术条件》两项新标准。其中，JB／T10406—2004《内燃机激光淬火气缸套技术条件》是首次发布，JB／T5083—2005《内燃机干式铸铁气缸套技术条件》则是对1991年版本的修订。     

凸轮轴工作表面强化处理工艺的研究

介绍了凸轮轴表面强化处理技术,分析了凸轮轴传统表面处理的特点及其存在问题,研究了凸轮轴激光表面热处理工艺及其质量影响因素。激光表面热处理后的凸轮轴表面淬硬层硬度有大幅度的增加,有利于提高凸轮轴表面抗疲劳强度。与现行的凸轮轴表面处理工艺相比,激光热处理工艺稳定、可靠,易于实现自动化,具有广阔的应用前景。     

Technologies and policies for the transition to a sustainable energy system in china

The paper highlights the energy dilemma in China’s modernization process. It explores the technological and policy options for the transition to a sustainable energy system in China with Tsinghua University’s Low Carbon Energy Model (LCEM). China has already taken intensive efforts to promote research, development, demonstration and commercialization of sustainable energy technologies over the past five year. The policy actions cover binding energy conservation and environmental pollution control targets, economic incentives for sustainable energy, and public R&D supports. In order to achieve the sustainable energy system transformation eventually, however, China needs to take further actions such as strengthening R&D of radically innovative sustainable energy technologies and systems such as poly-generation, enhancing the domestic manufacturing capacity of sustainable energy technologies and systems, creating stronger economic incentives for research, development, demonstration and commercialization of sustainable energy technologies, and playing a leading role in international technology collaborations.     

Review on solar-driven ejector refrigeration technologies

The objective of this paper is to provide a literature review on solar-driven ejector refrigeration systems and to give useful guidelines regarding background and operating principles of ejector. The development history and recent progress in solar-driven ejector refrigeration systems are reported and categorized. It shows that solar-driven ejector refrigeration technologies are not only can serve the needs for cooling requirements such as air-conditioning and ice-making and medical or food preservation in remote areas, but also can meet demand for energy conservation and environment protection. For these reasons, the research activities in this sector are still increasing to solve the crucial points that make these systems not yet ready to compete with the well-known vapour compression system. However, a lot of research work still needs to be done for large-scale applications in industry and for the replacement of conventional refrigeration machines.     

Microscale combustion: Technology development and fundamental research

The high energy density of hydrocarbon fuels creates a great opportunity to develop combustion based micro-power generation systems to meet increasing demands for portable power devices, micro unmanned aerial vehicles, micro-satellite thrusters, and micro chemical reactors and sensors. In this paper, the recent technological development of micro-power systems and progress in fundamental understanding of micro-scale combustion are reviewed. At first, micro-scale combustion regimes are categorized by using different physical and chemical length and time scales and the resulting non-dimensional parameters and their correlations to various combustion regimes for micro and mesoscale combustion are discussed. Secondly, the recent successful developments and technical challenges of micro-thrusters, micro internal combustion engines, and micro chemical reactors summarized. Thirdly, the underlying fundamental mechanisms and ignition and flame dynamics in micro-scale combustion are reviewed, respectively, in premixed, non-premixed, catalytic, and non-equilibrium, micro-scale combustion systems. The conventional concepts of combustion limits such as the flammability limit, quenching diameter, and flame extinction and heat recirculation are revisited. The unique thermal and chemical transport mechanisms such as flame structure interaction, radical quenching, non-equilibrium transport appearing in micro-scale combustion are discussed. New flame regimes and instabilities such as flame bifurcation, weak flames, flame cells/streets, thermal and kinetic quenching, flameless low temperature catalytic combustion, repetitive extinction and ignition, spinning flames, spiral and multi-branched flames, symmetric and asymmetric oscillating flames are discussed. Finally, an overview of future research and conclusion are made. The goal of this review is to present an overview of the development of micro-power generators by focusing more on the advance in fundamental understanding of micro-scale combustion.     

Harnessing biofuels: A global Renaissance in energy production?

Biofuel, peoples’ long awaiting alternative fuel, is yet to struggle a long way to reach in retail outlet all over the world as an economical and environmental friendly fuel. Biofuels include bioethanol, biodiesel, biogas, bio-synthetic gas (bio-syngas), bio-oil, bio-char, Fischer-Tropsch liquids, and biohydrogen. Among these bioethanol, biodiesel, biogas are predominant which can be produced either using chemical catalyst or biocatalyst from biomass. At present, the conventional process involves the chemical catalyst while a rigorous research is focused on using a biocatalyst. This review brings out the advantages and disadvantages of using different type of catalyst in biofuel production and emphasis on new technologies as an alternative to conventional technologies.     

Advances in waterless fracturing technologies for unconventional reservoirs

The application of conventional hydraulic fracturing technology has been greatly restricted especially in areas with water shortage and traffic inconvenience. At the same time, concern grows about water resources and environmental protection. More environmentally friendly new fracturing technologies, such as waterless fracturing technologies, can also make an important contribution to oil and gas exploitation. This paper reviews several kinds of waterless fracturing fluid technologies, including their working mechanisms, technical features, advantages, and disadvantages. This paper then explores the economics of the various technologies, and prioritizes them based on their advantages and disadvantages. It provides a reference point for theoretical research on and the practical application of waterless fracturing.     

风冷柴油机45~#钢凸轮轴激光强化工艺的产业化研究

本文介绍风冷柴油机４５＃钢凸轮轴激光强化工艺的科研成果向生产应用的转化．风冷柴油机４５＃钢凸轮轴激光强化在发动机 １０００ｈ可靠性考核中显示了优异的性能，证实了激光强化技术在生产中的工艺稳定性，其批量生产标志着我厂率先在国内实现了凸轮轴激光强化工艺产业化．     

Review of solar sorption refrigeration technologies: Development and applications

In this paper, a review of the research state of art of the solar sorption (absorption and adsorption) refrigeration technologies is presented. After an introduction of basic principles, the development history and recent progress in solar sorption refrigeration technologies are reported. The application areas of these technologies are categorized by cooling temperature demand. It shows that solar-powered sorption refrigeration technologies are attractive alternatives that not only can serve the needs for air-conditioning, refrigeration, ice making and congelation purposes, but also can meet demand for energy conservation and environment protection. However, a lot of research work still needs to be done for large-scale applications in industry and for the replacement of conventional refrigeration machines.     

汽车节油减排措施和政策

交通运输用油是影响我国石油消费量的重要因素．汽车的节油与燃料替代对降低石油需求起着关键性的作用．也是实现经济、社会和能源安全以及过渡到低碳经济的关键。汽车节油效果取决于国家的宏观政策。提高传统汽车能源效率、鼓励替代燃料和新能源汽车开发,以及采用智能运输系统、大力发展公共交通是节油减排的有效途径。提高汽车燃料使用效率．即开发节油型汽车、降低燃料消耗、淘汰油耗较高的老旧车型、提高柴油发动机所占比例等。整合强制性燃油经济性标识、标准和财政激励措施等独立的政策形成一揽子计划．通过相互协同作用来增强效果。替代燃料和新能源是石油燃料的有效补充,应加大投入力度。其中最有前景的是天然气、液化石油气等气体燃料。混合动力、纯电动汽车可借鉴国外先进技术,实现跨越式发展。氢燃料电池汽车应加大研发力度。充分利用智能运输系统和先进的物联网系统优化交通结构和货运行程,大力发展公共交通。