CAD/CAE/CAM在汽车制造中的应用及发展

汽车工业在我国制造业中占有极为重要的地位,逆向工程、虚拟制造、CAD/CAM/CAE等一系列新技术、新方法,对汽车工业的发展发挥了巨大的推动作用。本文从CAD/CAM/CAE技术的角度,对其在整车设计开发、覆盖件生产和系列化零件模具制造中的应用做了简要分析,探讨了CAD/CAM/CAE技术的有效性和重要性,验证了CAD/CAM/CAE技术是汽车制造向着信息化、智能化、标准化发展,同时实现高质量、低成本、短周期的重要保障。     

基于CAD/CAE/CAM的模具数字化设计与制造技术

模具的数字化设计与制造是现代模具发展的方向,运用CAD/CAE技术进行注塑模具设计与分析,运用CAM技术完成模具型芯及型腔等模具零部件的数控编程和加工仿真,可大大提高模具设计的高精尖程度,缩短模具设计与制造周期,降低模具生产成本。文章简要介绍了CAD/CAE技术在注塑模具设计中的应用以及CAM技术在注塑模具制造中的应用,展望了CAD/CAE/CAM在模具领域的未来前景,强调了模具数字化设计与制造基于CAD/CAE/CAM技术的重要性。     

CAD/CAE/CAM技术在塑料注塑模具中的应用

以手机外壳注塑模具为例,综述CAD/CAE/CAM技术在塑料注塑模具中的应用。     

CAD/CAE/CAM一体化技术在称重传感器开发中的应用

本文介绍了CAD/CAM/CAE一体化技术的发展和现状.结合称重传感器设计开发的实例,展示了基于Pro/Engineer平台的CAD/CAE/CAM一体化开发流程.实践证明,CAD/CAE/CAM一体化技术为今后称重及其他同类测力传感器的开发提供了一种快速且易于标准化的开发方法,具有很大的应用潜力.     

基于Internet CAD/CAE/CAM/ERP的挤出模具开发设计及制造

通过构建基于Internet技术的综合信平台、基于ERP和基于并行工程的CAD/CAE/CAM系统的智能化局域网络系统,分析CAD/CAE/CAM/ERP在挤出模具开发、设计及制造中的应用.     

CAD/CAM/CAE技术在模具生产中的应用

介绍了CAD/CAE/CAM技术在模具制造过程中的应用，阐述了CAD/CAE/CAM技术可以缩短生产周期，提高经济效益。     

基于CAD/CAE/CAM技术的吊钩注塑模设计与加工

以吊钩注塑模具设计与制造过程为例,研究应用Creo、华塑CAE、CAXA制造工程师等软件完成注塑模具CAD/CAE/CAM的一体化过程。详细介绍了采用华塑CAE软件对塑件CAE软件对塑件进行CAE分析的一般流程,包括网格划分、充模及翘曲分析等。结合分析结果,在Creo2.0中完成模具设计的全过程,最后将曲取的模具零件通过转存格式的方式供CAXA制造工程师调用,完成零件的仿真模拟加工。     

基于UG的注塑模具的设计及加工

笔者采用UG作为模具开发的平台,利用其强大的CAD/CAE/CAM功能,在建模(Modeling)、注塑模向导(Mold wizard)、加工(Manufacturing)三大模块下完成的模具设计与加工工作,并对仿真过程中出现的弊端提出物理仿真.UG这种先进的CAD/CAE/CAM一体化软件在模具行业中的应用,减少了模具设计制造的周期,取得了显著的经济效益.     

基于UG软件的灯头注塑模具设计

UG软件系统功能强大,应用广泛,在模具设计和制造行业具有很大的优势.文章探讨了基于UG平台实现注塑模具CAD/CAM/CAE的方法和途径.基于企业生产实际需求,对探照灯灯头模具进行了设计加工,依此阐述了注塑模具CAD/CAM/CAE的实现过程.     

汽车计算机辅助技术与CAD/CAE/CAM软件选型方法

介绍汽车计算机辅助技术的内容、应用效果、发展趋势和CAD/CAE/CAM软件选型方法。     

Electron and light microscopy studies on the domain structures of Zn3B7O13Cl, Zn3B7O13Br and Zn3B7O13I ferroic boracites

The domain structures of Zn₃B₇O₁₃Cl, Zn₃B₇O₁₃Br and Zn₃B₇O₁₃I boracite single crystals were studied by means of polarized light in conjunction with electron microscopy. Single crystals of the three compositions were grown by chemical transport reactions in closed quartz ampoules, at a temperature of 900 °C and were examined by polarizing optical microscopy (PLM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). For both PLM and SEM, the same as‐grown samples were used without having to resort to metallization of the crystal faces. For TEM the single crystals were crushed and mounted on holey carbon films. Comparative electron microscope images were useful for revealing the domain structure of these ferroelectric/ferroelastic materials previously observed between the crossed polars of an optical microscope. X‐ray diffraction analysis of the pulverized crystals was performed for this triad of halogen boracites containing zinc as a common metal.     

Cylindrical specimens for KIC of rocks

Stress intensity factors for pairs of diametrically opposite radial cracks on the inside of a jacketed pressurized hole in a thick cylinder have been calculated by using finite element technique. Burst tests on thick cylinder rock samples under above conditions have been performed and the K_IC values for Antrim Shale and Limestone determined. The method is very convenient for rocks whose samples are often available in form of cylindrical bars drawn as cores from underground drilling.     

GT/CAD/CAPP/PDM/ERP系统集成研究

研究ETO生产方式下以成组技术为基础的CAD/CAPP/PDM/ERP的集成方法,包括面向CAD/CAPP/PDM/ERP的集成的成组信息编码,基于成组编码的CAD/PDM集成、CAPP/PDM集成和PDM/ERP集成.提出了基于成组技术的CAD/CAPP/PDM/ERP集成框架,研究了贯穿于CAD、CAPP、PDM与ERP系统的统一的成组编码方案和信息编码方案.     

基于太赫兹光谱的人参和西洋参鉴别

为了快速区分人参和西洋参,依据两者所含的人参皂苷在太赫兹波段具有不同指纹光谱,提出了一种基于人参皂苷的太赫兹光谱鉴别人参和西洋参的方法。采用MATLAB软件识别人参和西洋参的太赫兹光谱,同时根据太赫兹光谱特征并通过标准的主成分分析(PCA)区分出人参、西洋参。实验结果表明,基于太赫兹光谱的主成分分析可精确区分出人参、西洋参,并且还可以应用于其他类似物质的区分中。     

Analysis of the Rk surface roughness parameter proposals

European manufacturers have proposed a set of surface roughness parameters based on an examination of the variation in slope of the bearing ratio curve of a surface profile. It is shown, that the proposed procedure provides no useful information, and indeed is misleading, since the bearing ratio curve of even a normally-distributed random surface profile exhibits the expected variation in slope when plotted on rectangular coordinates. On the other hand, the desired information is readily obtained by a similar examination of the cumulative height distribution of a surface profile (the unity complement of the bearing ratio) when it is plotted on normal probability coordinates.     

永磁同步电机积分滑模观测器控制

对永磁同步电机观测器控制进行研究,针对传统滑模观测器存在控制精度低、系统抖振较大的不足,设计了一种永磁同步电机积分滑模观测器控制。积分滑模控制具有控制精度高、系统抖振小的特点。积分滑模观测器可以有效提高电机控制精度,增强控制系统抗干扰能力。采用饱和函数代替符号函数进行滑模控制律设计,降低控制系统固有抖振,使滑模控制动态性能提高。通过仿真验证了积分滑模观测器控制策略的可行性。     

Characterization of cast Al86Mn3Be11 alloy

An Al₈₆Mn₃Be₁₁ alloy cast into copper mould was subjected to metallographic investigation. The as-cast microstructure consisted of a quasicrystalline icosahedral phase (i-phase), Be₄AlMn phase and, occasionally, a hexagonal phase. Al-rich solid solution represented the dominant phase. The chemical compositions of phases were determined using AES. The composition of the Be₄AlMn slightly deviated from the stoichiometric composition, whereas the composition of the i-phase was approximately Al₅₂Mn₁₈Be₃₀, containing an appreciable amount of Be. The average composition of the hexagonal phase was Al₆₆Mn₂₁Be₁₃. Deep etching and particle extraction provided a deep insight into the three-dimensional morphology of the i-phase and the hexagonal phase, whereas Be₄AlMn was slightly attacked by the etchant. The i-phase was present predominantly in the form of dendrites and a rodlike eutectic phase. The hexagonal phase was primarily in the form of hexagonal platelets, whereas Be₄AlMn was rather irregular in shape. The morphology of the i-phase can be explained by predominant growth in 3-fold directions and the lowest energy of the 5-fold planes, leading to the faceting and adopting a pentagonal dodecahedron shape. The brightnesses of phases in the backscattered electron images were rationalized by determining their backscattering coefficients. TEM investigation showed considerable phason strain in the i-phase, and the polycrystalline nature of the Be₄AlMn phase.     

Investigation on the impact behavior of Al2O3-SiC-MgO nanoceramic/metal laminated composite

Lightweight laminated composites containing a ceramic front layer and a metallic backing layer were used in order to protect people, moving equipment, and mobile vehicles from high velocity impact and the increased mobility of mobile vehicles. In this study, by adding10 vol% SiC and 500 ppm MgO nanoscale particles on the microstructure of Al ₂ O ₃ matrix and applying optimum sintering conditions, ceramic performance against high-speed projectile impact was improved. To perform this investigation, a number of target samples with two different types of front layers (alumina and Al ₂ O ₃-SiC-MgO nanocomposite ceramic) were produced. Impact tests were conducted on these samples using 7.62 mm projectiles with a velocity of 820 ± 15 m/s. The amount of bulge and bending of the backing layer caused by impact tests was measured. The results of the impact tests on the samples made of Al ₂ O ₃-SiC-MgO nanocomposite ceramics and alumina were also compared and analyzed. The results indicate that the substitution of Al ₂ O ₃-SiC-MgO ceramic layer — which is proffered in this paper — instead of pure alumina ceramic layer, decreases the areal-density of the samples by at least 30% and improves mechanical properties by about a 60% increase in flexural strength and 100% growth of the energy distribution factor, which impressively increases impact energy absorption.     

Electron microscopy of crack/particle interactions in Al2O3/SiC nanocomposites

Crack/particle interactions in alumina/silicon carbide nanocomposites have been investigated by scanning electron microscopy and transmission electron microscopy, with cracks induced by Vickers microindentation. Intergranular cracks are frequently deflected into grains by SiC particles on grain boundaries inclined to the average direction of crack propagation. This mechanism is proposed to explain the change in the fracture mode from intergranular fracture for monolithic alumina to predominantly transgranular fracture for the nanocomposites. Neither stress-induced microcracking around SiC particles nor significant crack deflection by intragranular particles was found to occur in the nanocomposites. It is argued that an addition of nanoparticles may not be a promising approach for increasing the toughness of alumina.     

Near-field second harmonic imaging of the c/a/c/a polydomain structure of epitaxial PbZrxTi1–xO3 thin films

Near-field optical second harmonic microscopy has been applied to imaging of the c/a/c/a polydomain structure of epitaxial PbZr _x Ti_{1– x} O₃ thin films in the 0 <  x  < 0.4 range. Comparison of the near-field optical images and the results of atomic force microscopy and X-ray diffraction studies show that an optical resolution of the order of 100 nm is achieved. Symmetry properties of the near-field second harmonic signal allow us to obtain good optical contrast between the local second harmonic generation in c- and a-domains. Experimentally measured near-field second harmonic images have been compared with the results of theoretical calculations. Good agreement between theory and experiment is demonstrated.