Outlining policy responses to stimulate automotive car demand by environmental impact reduction

The aim of this paper is to propose an alternative approach for outlining policy responses to stimulate the automotive industry. The scientific community has developed and employed the Delphi method to collect and convey perspectives and impressions, and also define a number of financially viable proposals. The panel of experts takes the view that traditional industrial policy measures denote limited effects to stimulate car demand, in a context of a macro-economic downturn. By contrast, the panel also believe incentives for car demand are important for environmental purposes, for safety and for the diversification of energy sources. The policy measures proposed are fundamental from the viewpoint of overturning path dependencies in the automotive industry which impede the diffusion of alternative vehicles, with respect to business models and consumer attitudes.     

Construction of evolving models for the environmental evaluation of innovative sub-systems based on a hierarchical agglomerative clustering

This paper deals with simplifying the environmental evaluation of an innovative sub-system related to the future complex system that will include it, by using evolving generic models built on a limited number of characteristics. For a complex system range, the evolving approach of the environmental modelling aims to generate a learning dynamics, to avoid the paralysing complexity induced in design by the valuation of many components according to many impact categories. Applied to the automotive sector, dendrograms are made with results of life cycle assessments (LCA) of 17 vehicles for 4 environmental indicators and on 3 life cycle steps. In an iterative process, a limit condition threshold on the resulting relative errors aims to cluster the vehicles. First, several calculation methods of dendrograms are tested. Second, the influence of the limit condition on the models is observed. Lastly, by simulating the vehicle population increase, the modelling capacity to evolve is tested. Five vehicle characteristics are sufficient to identify a model to be equivalent to the future vehicle. While the number of clusters is increased to simplify their identification with the system characteristics, the relative error variability increases too. The generic models are stable when adding LCA's results.     

Dynamic Mechanical Properties of Soy Protein Filled Elastomers

Dynamic mechanical properties including temperature effect, stress softening, and Payne effect are studied on the elastomer composites filled with soy protein or carbon black. The comparison of protein composite with well-known carbon black composites provides further insight into the protein composites. The elastomers filled with soy protein aggregates give substantial reinforcement effect when compared with the unfilled elastomers. Approximately 400 times increase in shear elastic modulus was observed when 40% by weight of protein is incorporated into the elastomers. The sample films were cast from the particle dispersion of soy protein isolate and carboxylated styrene–butadiene latex. At the higher temperatures, the shear elastic modulus of soy protein-filled composites does not decrease as much as that of the carbon black-filled composites. The behavior of elastic and loss modulus under the oscillatory strain of different magnitude is similar to that of carbon black reinforced styrene–butadiene rubber. However, carbon black composites show a better recovery behavior after eight cycles of dynamic strain. The reduction of shear elastic modulus with dynamic strain (Payne effect) was compared with Kraus model and the fitting parameter related to the aggregate structure of the soy protein. A reasonable agreement between the theoretical model and experiment was obtained, indicating the Payne effect of the protein-related network structure in the elastomers could also be described by the kinetic agglomeration de-agglomeration mechanism.     

Kenaf/Ramie Composite for Automotive Headliner

An increasing industrial interest is applications of kenaf and ramie fiber nonwovens for making automotive interior trim parts because of their excellent strength and renewability. This paper presents a study on the manufacture and evaluation of the kenaf/ramie nonwoven composite for this automotive end use. Carding, needle-punching, and wet bonding were used to fabricate the composite. End-use performance of the composite, in terms of tensile strength, thermal conductivity, dynamic mechanical property, and bonding structure, was tested using a series of instruments in accordance with the ASTM methods. Bonding performance of the polyvinyl alcohol binder and acrylic copolymer binder was also compared. Research results revealed that the acrylic-copolymer bonded composite was significantly anisotropic in both tensile and bending deformation and the polyvinyl-alcohol bonded composite was significantly anisotropic only in bending deformation. For the acrylic-copolymer bonded composite, increase of padding times helped enhance tensile properties. The acrylic-copolymer bonded composite also exhibited a better performance in dynamic thermal mechanical deformation but indicated insignificant difference of thermal conductivity compared to the polyvinyl-alcohol bonded composite.     

Mechanical performance of woodfibre–waste plastic composite materials

Plastic products used for packaging are often discarded after a single use resulting in an inexhaustible supply of waste polymeric materials. The stiffness and strength of polymeric materials have been known to improve with the addition of lignocellulosic fibres available in abundance in nature. Hence, composite materials containing natural fibres and waste plastics would result in the reduction of solid wastes and the use of cheap, renewable resources. Composite specimens, consisting of waste plastics obtained from a Kerbside collection (high density polyethylene (HDPE) waste, Janitorial waste, Kerbside waste I and Kerbside waste II) and Pinus radiata woodfibres (medium density fibres (MDF)), have been produced through melt blending and injection moulding. The effects of fibre content, matrix type and interfacial bonding on the tensile and flexural properties of these composite materials have been determined through extensive testing at various conditions. The mechanical properties of these composites at room temperature and humidity depend on the amount of woodfibres, the mechanical properties of the waste plastics used and the presence of a suitable coupling agent. The tensile strengths of MDF/waste plastic composites do not generally change with fibre content except for 40% MDF/HDPE waste and 40% MDF/Kerbside waste II (plus 1% Epolene™) composites, where the tensile strengths increase by about 25% compared to those of the corresponding waste plastics. Flexural strengths of MDF/waste plastic composites increase with the addition of medium density fibres with the exception of MDF/Kerbside waste I composites. The tensile and flexural moduli of MDF/waste plastic composites mostly increase with increasing fibre content.     

轿车后轴纵臂内高压成形研究

用400MPa内高压成形机对轿车后轴纵臂进行内高压成形试验研究,设计了合理的模具结构,包括分模面和冲头密封形式。分析了矩形截面圆角成形特点和所需成形压力计算公式,制定出合理的内高压工艺和参数,成功地试制出轿车后轴纵臂,经检测尺寸满足设计要求。     

汽车产品回收利用技术及商业循环模式的实现

探讨了汽车产品回收利用技术实现的方案。实现汽车的全生命周期,需要经过汽车整车拆解、汽车零部件分类以及汽车零部件再制造或资源化回收这三大步骤,并对这三项内容加以具体阐述。结合现行报废汽车产业政策,提出了一种实现汽车产品回收的商业循环模式。说明了汽车产品回收再制造信息管理系统的重要性,并介绍了其六项功能。     

聚合物基复合材料老化性能研究进展

分析了湿热老化、化学侵蚀和大气老化对复合材料的作用机理及对其力学性能的影响,阐述了上述环境作用下的聚合物基复合材料腐蚀寿命预测模型,提出了存在的主要问题及今后的发展趋势。认为材料腐蚀机理的细节、环境因素之间的交互作用、不同方法和装置之间的相关性是今后的研究重点。     

生物硫铁复合材料处理含铬废水及铬资源化研究

研究了由硫酸盐还原菌(SRB)与其原位生成的纳米硫铁化合物组成的生物硫铁复合材料(生物硫铁)的耐铬性能和再生性能,并利用其再生特性,设计了处理高浓度含铬废水及铬资源化的还原-再生循环处理工艺.结果表明,生物硫铁处理含铬废水后,污泥中的SRB仍具有活性,能以反应产物Fe3+和S单质为电子受体,重新生成生物硫铁;而且SRB在Cr(VI)浓度600mg/L的废水中仍能存活并逐渐将Cr(VI)去除.还原-再生循环处理工艺处理含铬废水结果表明,出水Cr(VI)低于0.019mg/L,总Cr低于0.929mg/L,能达标排放.经10个循环处理后污泥中铬(Cr2O3)含量达到40.47%,铬铁比达到6.98,污泥达到冶金级(湿法冶炼铬)铬矿标准和化工级铬矿标准,可资源化利用.     

汽车内外饰件常用刮擦试验方法及应用

本文阐述了刮擦试验的原理,从试验样品准备、试验条件、试验结果评价等方面分析和总结了刮擦试验的技术要点;对目前主要汽车企业常用的汽车内外饰件刮擦试验方法及其应用作了介绍,并分析了刮擦试验方法的发展趋势。