模具的CAD/CAE/CAM技术

介绍铸造模、锻模、级进模、汽车覆盖件模和塑料注射模CAD/CAE/CAM技术的发展概况,并论述了模具CAD/CAE/CAM技术的最新开发成果和发展趋势.     

压铸模CAD/CAE/CAM的研究现状与发展

分析中国压铸模设计与制造的现状:基本满足汽车、摩托车、电机、家电、仪表、灯具、电子行业的需要.存在的问题:模具标准化和专业化水平不足.介绍国外压铸模CAD/CAE/CAM的研究进展:是近无余量铸造的发展方向.根据中国压铸模CAD/CAE/CAM技术研究与开发存在的问题,提出发展中国压铸模CAD/CAE/CAM的7项对策.     

模具CAD/CAE/CAM的发展概况及趋势

介绍了级进模、汽车覆盖件模和塑料注射模CAD/CAE/CAM的发展概况并论述了这三种模具CAD/CAE/CAM的最新开发成果和发展趋势。     

CAM技术在工模具加工中的应用

简介CAD/CAM/CAE技术,以实例说明CAM技术在模具加工中的关键问题,利用Pro/E获取模具三维模型、实现CAD/CAM系统集成、数控加工等系列过程,从而缩短了模具的设计、制造周期,提高了模具品质.     

我国压铸模CAD/CAE/CAM及其一体化技术

分析了国内压铸模CAD/CAE/CAM技术的发展概况 ,探讨了压铸模CAD/CAE/CAM一体化的主要内容 ,并就发展我国压铸模CAD/CAE/CAM及其一体化技术提出了几点建议和思考     

基于CAD/CAE/CAM技术的数字化注射模设计研究

随着制造业的迅速发展,传统的模具设计方法根本不能满足市场对模具的要求,而计算机辅助技术的应用在提高模具精度、缩短模具设计周期等方面有很大优势.因此在现代化模具生产的过程中,应用CAD/CAE/CAM技术实现模具的数字化设计与制造,显得尤为重要.本文以对汽车后视镜盖注模射设计研究为例,采用CAD/CAE/CAM技术的数字化模具设计方法对其进行研究,结果表明:此研究方法提高了模具设计的效率,加速了模具的研究与开发.     

我国模具CAD/CAE/CAM/PDM发展现状及发展建议

1 我国模具CAD/CAE/CAM/PDM发展现状 模具CAD/CAE/CAM是改造传统模具生产方式的关键技术,是一项高科技、高效益的系统工程.它以计算机软件的形式,为企业提供一种有效的辅助工具,使工程技术人员借助于计算机对产品性能、模具结构、成形工艺、数控加工及生产管理进行设计和优化.模具CAD/CAE/CAM技术能显著缩短模具设计与制造周期,降低生产成本和提高产品质量已成为模具界的共识.     

压铸模CAD/CAE/CAM技术现状及发展趋势

综述了国内外压铸模CAD/CAE/CAM技术现状,在此基础上,提出了压铸模CAD/CAE/CAM需解决的部分关键技术及发展趋势.     

铝型材挤压模具CAD/CAE/CAM集成系统研究

论述了铝型材挤压模具CAD／CAE／CAM集成系统的特点，介绍了CAD／CAE／CAM技术的应用现状，提出了CAD／CAE／CAM一体化导示图，指出了CAD／CAE／CAM集成系统的发展方向。     

压铸模CAD/CAE/CAM

介绍了压铸模CAD／CAE／CAM一体化技术的主要内容和实现CAD／CAE／CAM一体化的技术路线。实践应用表明，CAD／CAE／CAM一体化技术能有效地指导压铸模具的设计、模拟分析与制造过程，提高模具结构的合理性、准确性和加工精度，服务于实际压铸件生产。     

Structural, mechanical and corrosion properties of TiOxNy/ZrOxNy multilayer coatings

Results on the deposition and characterization of TiO_xN_y/ZrO_xN_y multilayers, with bilayer periods of 20 and 400 nm, are presented. The coatings were deposited on TiNiNb alloy substrates by the pulsed magnetron sputtering method. The elemental composition, hardness, adhesion and corrosion resistance of the coatings were analyzed.As resulted from the XPS analysis, the individual layers consisted of a mixture of titanium or zirconium oxynitrides and corresponding oxides. X-ray analysis revealed that the coatings were amorphous. Only slight differences between the microhardness and adhesion values of the coatings with small and large bilayer period Λ were found. The experiments also showed that the multilayered coatings improved the corrosion resistance of the uncoated alloy and reduced the amount of ion release in artificial body fluids.     

生物医用NiTi形状记忆合金腐蚀研究进展

镍钛形状记忆合金(NiTi-SMA)具有较好的耐腐蚀和机械性能,在口腔和临床医学中有着大量而广泛的应用。NiTi-SMA腐蚀后释放Ni²⁺会引发细胞毒性和过敏反应,进一步提高NiTi-SMA的耐蚀性是目前生物医学材料领域发展的核心之一。本文对近年来国内外有关口腔医学和临床医学中常用NiTi-SMA的腐蚀研究现状进行了总结,同时也对NiTi-SMA增材制造及表面改性技术进行了评述,以期为开发高性能抗腐蚀生物医用NiTi-SMA提供一定的指导意义。     

Li掺杂Ba(Ti1/7Sn1/7Zr1/7Hf1/7Nb1/7Ga1/7Li(1/7-x))O3高熵陶瓷的制备及介电性能研究

近年来,在高熵合金基础上发展起来的高熵陶瓷逐渐引起了研究者的广泛关注,其出现为开发高性能的无机非金属材料提供了新的设计思路。本文采用固相法制备了BaMO3基钙钛矿型高熵陶瓷Ba(Ti1/7Sn1/7Zr1/7Hf1/7Nb1/7Ga1/7Li(1/7-x))O3 (x = 0, 2.3%, 5.3%, 8.3%, 11.3%),并研究了Li含量对高熵陶瓷物相结构、微观形貌及介电性能的影响。结果表明,Li含量对陶瓷结构的影响不大,陶瓷均保持立方钙钛矿结构,且无杂相产生;陶瓷的晶粒尺寸相对较均匀。当x = 0时,即B位七元等摩尔比Ba(Ti1/7Sn1/7Zr1/7Hf1/7Nb1/7Ga1/7Li1/7)O3高熵陶瓷,其介电常数达到了最大值2920 (@100 Hz),相较于已报道的不掺Li的六元高熵钙钛矿陶瓷Ba(Ti1/6Sn1/6Zr1/6Hf1/6Nb1/6Ga1/6)O3提升了近50倍。     

MOCVD growth and characterizations of BxAl1−xAs and BxAl1−x−yInyAs alloys

Zinc-blende B_xAl_1−xAs and B_xAl_1−x−yIn_yAs alloys have been grown on exactly oriented (0 0 1)GaAs substrates by low pressure metalorganic chemical vapor deposition (LP-MOCVD). The influence of susceptor coating, growth temperature and gas-phase boron mole fraction on boron incorporation into AlAs has been comprehensively investigated. It has been found that boron incorporation into AlAs could be enhanced and the optimal growth temperature range of B_xAl_1−xAs alloys changed from 580 °C to 610 °C when SiC-coated graphite susceptors were replaced by the non-coated ones. In this study, the maximum boron composition x of 2.8% was achieved for the pseudomorphically strained B_xAl_1−xAs alloys. AFM measurements show that RMS roughness of B_xAl_1−xAs alloys increased sharply with the increase of gas-phase boron mole fraction. Raman spectra of B_xAl_1−xAs alloys show a linear increase of the BAs shift with boron composition x. Based on BAlAs deposition, bulk B_xAl_1−x−yIn_yAs (x = 1.9%) quaternary alloy was grown lattice-matched to GaAs successfully. Moreover, 10-period BAlAs/GaAs and BAlInAs/GaAs MQW heterostructures were also demonstrated.     

Ag/LaNixCo1-xO3触点材料的制备及电接触性能研究

本文运用溶胶-凝胶燃烧法合成了双钙钛矿型LaNixCo1-xO3(LNCO)纳米材料,利用粉末冶金和热挤压技术制备了相应的Ag/LNCO触点材料及元件样品。重点考察了不同Ni、Co含量对Ag/LNCO触点材料微观结构、物相组成、物理性能、力学性能及电寿命服役能力的影响,对其电弧侵蚀失效行为进行了研究,并与SnO2粉体增强Ag基触点材料进行对比。结果表明:溶胶凝胶法合成的LNCO纳米颗粒粒径为20-30 nm,经粉末冶金工艺制备的Ag/LaNi0.5Co0.5O3触点材料电学性能和电寿命都优于Ag/SnO2触点材料,其电阻率低至2.10 μΩ?cm,电寿命性能达到51287次。表明Ag/LaNi0.5Co0.5O3触点材料性能较佳,是一种可以取代Ag/CdO的新型触点材料。     

Hydrothermal synthesis of superconductors Ba1−xKxBiO3 and double perovskites Ba1−xKxBi1−yNayO3

Superconductors Ba_1−xK_xBiO₃ and body-centered double perovskites Ba_1−xK_xBi_1−yNa_yO₃ have been selectively synthesized by a facile hydrothermal route. The appropriate ratio and adding sequence of initial reagents, alkalinity, reaction temperature and time are the critical factors that influence the crystal growth of the compounds. The purity and homogeneity of the crystals were detected by the ICP, SEM, EDX and TEM studies. Magnetic measurements show that the superconducting transition temperatures T_C of Ba_1−xK_xBiO₃ decrease from 22 K (for x = 0.35) to 8 K (for x = 0.55) with increasing the K doping level.     

Magnetic phase diagrams of the TbRh2−xPdxPdxSi2 and TbRu2−xPdxSi2 systems

The a.c. susceptibility and high field magnetization on TbRh_2−xPd_xPd_xSi₂ and TbRu_2−xPd_xSi₂ compounds were investigated up to 140 kOe. The (T,x) magnetic phase diagrams were determined. For both systems, an increase in the Pd content causes a decrease in the Néel temperature and changes the magnetization curves.     

High strength and good ductility of casting Al-Cu alloy modified by PrxOy and LaxOy

A modified Al-Cu alloy with high tensile strength and ductility of about 574.0 MPa and 10.4%, respectively, was obtained by adding multiple rare earth oxides (Pr_xO_y and La_xO_y) as modifier. Compared with the unmodified Al-Cu alloy, the tensile strength and ductility of the modified sample were increased by 24.3% and 42.5%, respectively. The improvement both in the strength and ductility may attribute to the finer crystal grains and dendrites, more homogeneously distributed θ′ phase precipitates and the intermetallic compounds formed at the crystal grain boundaries as well as in the space of the dendrites.     

Si3N4/Ti/Cu/Ni/Cu/Ti/Si3N4二次部分瞬间液相连接强度

采用Ti/Cu／Ni中间层对Si3N4陶瓷进行二次部分瞬间液相(PTLP)连接，研究连接工艺参数对Si3N4／Ti/Cu／Ni连接强度的影响，同时研究了连接强度随试验温度的变化规律。结果表明，在该试验条件下，室温连接强度随着二次连接温度的提高和二次保温时间的延长而提高，改变连接工艺参数对Si3N4／Ti/Cu／Ni二次PTLP连接界面反应层厚度无明显影响；连接强度在试验温度400℃时达到最大，随后随试验温度升高，连接强度降低，但在800℃前，其高温强度具有很好的稳定性。