铝合金在汽车轻量化中的应用及其前瞻技术

汽车工业的发展是人类文明与社会进步的重要标志,也是经济发展的强大动力;汽车工业是高新技术的最大载体;汽车工业与技术的发展与中国的经济发展息息相关,汽车工业已成为中国的支柱产业。尤其在2000年以后,中国汽车工业发展已进入快车道,并已成世界汽车生产大国和世界上最有潜力的消费市场。     

清洁汽车行动相关标准的现状和发展趋势

一、前言环境和能源问题是影响可持续发展的重要因素。汽车保有量不断增长使全世界特别关注如何通过技术的发展减少汽车带来的环保与节能问题 ,汽车清洁化成为一个重要的方向。近年来 ,美国、欧洲和日本等发达国家相继推出了包括电动汽车、混合动力汽车和燃料电池汽车在内的多种汽车产品及相关技术。中国作为一个发展中国家 ,对全球环境保护同样承担着重要责任。我国政府高度重视环保问题 ,把环境保护确定为一项基本国策。“九五”期间国家加大了对环保产业的投入 ,为促进汽车工业的技术进步 ,1999年 4月开始实施“空气净化工程———清洁汽…     

节能与新能源汽车重大项目研发

经过多年建设,吉林大学混合动力汽车课题组已具备了较先进的混合动力汽车研发条件,形成了以混合动力汽车仿真计算平台、混合动力汽车多能源动力总成控制器软硬件开发平台及混合动力汽车多能源动力总成控制器试验台（中图）为主的研发机构。     

大众汽车蓝驱技术的节能环保理念分析

在汽车工业高速发展的今天,能源和污染问题形式严峻,怎么做到既能节约能源、减少,保护我们赖以生存的环境。又能保证汽车有充沛动力性,＂蓝驱技术系列＂大众汽车是汽车行业的领军者,具有超强的技术实力,具有节能与环保,价格经济等优点,已经成为消费者比较认可的一系列环保节能汽车。该项目致力于降低汽车的油耗和排放。体现了大众汽车节能环保的宗旨。本文对大众蓝驱技术系列技术原理及应用做初浅的探讨。     

新能源汽车之产商新政

<正>新能源制高点的争夺是决定汽车行业未来格局的一场战争,在这样的一场关乎未来的争夺中,各大汽车企业都做了什么?他们的准备情况到底如何?新能源汽车成为竞争焦点从全球的汽车市场来看,新能源汽车目前正处于产业化突破的紧要关头。国际汽车巨头,如通用汽车、丰田等跨国公司都出台了具体的混合动力技术普及方案。而且各具特色。致力于氢动力技术发展的宝马公司去年推出全球首款氢动力豪华高性能轿车BMWHydrogen7,丰田率先推出了混合动力车,通用有了"氢燃料",大众也不遗余力地推动节能环保相关产品。     

新材料在汽车轻量化中的应用

<正>随着工业化和城市化进程的推进,全球对环境和资源保护的意识不断增强。世界各国在发展经济的同时,越来越注重生态环境的协调发展,绿色环保和节能减排成为发展主题。在此形势下,作为能源消耗和排放大户的汽车工业要想实现可持续发展必须降低燃油消耗,减少污染排放。目前,主要有3种途径解决汽车的节能、环保与安全问题,一是发展新能源汽车,二是发展先进发动机技术,三是实现汽车的轻量化[1]。新能源汽车是发展方     

新能源汽车技术展望

20世纪60年代末,资源稀缺、环境保护问题的提出,使汽车工业的发展面临着新的课题.一方面,发展节能汽车以解决现阶段产业发展、能源紧张和节能环保问题;另一方面,开展新能汽车研究,实现车用能源多元化,保障汽车能源的可持续供应.本文以燃料电池汽车为例,探讨新能源汽车的技术问题.     

客车技术的发展现状与发展趋势

混合动力汽车技术的发展与我国能源发展战略紧密结合，是解决我国能源安全与环保问题的重要汽车技术。因此，大力推进混合动力汽车产业化，是我国汽车工业现阶段和今后相当长的一个时期内，解决环保和能源问题、发展经济最有效的举措之一。     

汽车节能技术浅析

节能环保是汽车工业可持续发展的必由之路,也是制约其快速发展的瓶颈。积极发展汽车节能环保技术,降低车辆油耗,符合我国能源供应实际和汽车行业发展趋势。站在不同的角度,汽车节能有不同的方法,汽车生产商关注的是从汽车硬件上研究开发节能新技术,驾驶员能做到的是运用科学的驾驶方法,将车辆保养到最佳状态来减少不必要的油耗,从道路运输考虑的则是从管理上减少车辆总体的油耗,本文重点分析汽车节能硬件技术。     

我国汽车空调业发展面临诸多挑战——访上海交通大学汽车工程研究院汽车空调技术研究所所长陈江平

正"中国汽车工业是国际竞争的前线,汽车空调行业的竞争也是其中一个体现,虽然汽车空调技术与国外已没有太大的差距,但是从产业化发展角度来看,我国汽车空调的设计、开发、制造还面临诸多挑战。"采访伊始,上海交通大学汽车工程研究院汽车空调技术研究所所长陈江平言简意赅地道出了我国汽车空调行业的发展现状。从事汽车空调研究15年之久的陈江平老师,目前所研究的课题70%仍与汽车空     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...