【作者】 张子春；

【导师】 马力；

【作者基本信息】 武汉理工大学 ， 车辆工程， 2007， 硕士

【摘要】 本文首先介绍了国内外轻量化材料在汽车行业的应用及研究现状，重点介绍了复合材料的应用成果及进展，并提出用轻金属材料和复合材料对某商用车车架进行轻量化设计。随着我国经济水平的提高，人们在关注汽车油耗的同时也对乘坐舒适性提出了更高的要求。通过研究国内外汽车振动及平顺性研究历程及现状，针对国内对复合材料车架动态性能研究较少的现状，提出开展复合材料车架动态性能研究的构想。随后结合课题研究需要分析了某商用车车架的结构特点，建立了车架的有限元计算模型。根据该车的实际使用情况，分别设计了多种工况。按照所设计的工况对车架进行有限元计算，求出各种工况下的车架变形和应力分布情况，并进行了模态分析，为后续研究提供设计依据。接着采用铝合金材料和优化设计方法对车架进行重新设计，在满足车架强度和刚度要求的情况下，使车架达到最轻。设计结果表明，采用铝合金材料后，车架的自重可降低约65％。同样对铝合金材料车架进行了模态分析。根据复合材料的复合性能及发展趋势，在保证原车架结构形式基本不变的前提下，采用碳纤维增强环氧树脂基复合材料再次对车架进行重新设计。经过轻量化设计研究，得出一种刚度和强度都满足设计要求的设计方案。为使所设计的复合材料车架既能满足要求又能使其重量达到最轻，笔者采用有限元计算软件中自带的APDL开发语言编制出优化设计程序。优化设计表明，复合材料车架较原钢制车架重量降低幅度较大，降幅可达61％。为了研究复合材料车架的动态性能，笔者建立了包括驾驶室、货箱等在内的商用车整体计算模型，采用模态分析技术和随机振动谱分析技术对其进行进一步研究，研究表明复合材料车架较金属材料车架有较好的动态性能，为复合材料车架的精益设计提供了参考。本文的研究成果不仅为轻型材料在汽车领域的应用提供了新的思路，而且为国内复合材料在汽车主要承载结构上的设计及应用提供了参考。更多还原

【Abstract】 Firstly, this paper summaries the present application and research situation of light weight materials in the world, emphasizes the production and evolution of composite. Based on the collected information, I decide to do light weight design with light metal materials and composite. Going with improvement of standard of living, people are concerned about both oil consumption and riding comfort. After studying on course and recent situation of vehicle vibration and riding-comfort in the world, considering domestic research on dynamic performance of composite chassis is rare, a thought of research on dynamic performance of composite chassis is brought forward.Then structural characteristics of the commercial vehicle chassis are investigated according to research requirement and finite element model of the chassis is built up. Considering actual working situation, several working situation is designed and is applied to finite element calculation. From the results, deformation and stress distribution is derived in the different situation. A modal analysis is carried out afterwards. All the elementary studies above provide foundation for following chassis design.Subsequently, on the premise of strength and stiffness requirement, the chassis is redesigned to be lightest with aluminous alloy and optimized design method. From the design result, self-weight of the chassis can be reduced by 65%. A modal analysis is also carried out.In view of compound performance and composite developmental trend, a kind of carbon fiber composite (CFC) is used to redesign the chassis on condition that origin structure form is preserved. After design research, a project which meets the demand of strength and stiffness is elicited. In order to make sure of the weight of available chassis is lightest, ANSYS parametric design language (APDL) is used to develop optimization program. After optimization design, total weight of chassis can be reduced by 61%.In order to study dynamic performance of composite chassis, a calculational model including cab and carriage is established. After modal analysis and random vibration analysis, a conclusion is drawn that the composite chassis has better performance than the metal chassis, which can be a reference to excelsior design of composite chassis.All the researches and results in this paper can not only offer a new train of thoughts for application of light materials in vehicle, but also provide a reference for application of composite in main structure of vehicle.更多还原