CMS环境下基于智能优化算法的单元间布局问题研究*

研究了单元制造系统(CMS)设计中单元间布局设计问题,从单元制造系统的实际出发,提出了一种基于割树(Slicing-tree)的单元间布局设计模型.该模型考虑了单元形状约束、单元I/O点位置优化等诸因素对布局结果的影响.针对基于割树的描述形式,采用遗传算法求解,提出了一种新的割树编码方案,克服了以往编码方案易产生非法子串、不能覆盖整个解空间以及实现困难等缺点.计算结果表明,该算法是有效的、可行的.     

Direct-Ink-Writing of Electroactive Polymers for Sensing and Energy Storage Applications

Considering the high levels of materials used in the fields of electronics and energy storage systems, it is increasingly necessary to take into consideration environmental impact. Thus, it is important to develop devices based on environmentally friendlier materials and/or processes, such as additive manufacturing techniques. In this work, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) are prepared by direct-ink-writing (DIW) by varying solvent evaporation temperature and fill density percentage. Different morphologies for both polymers are obtained, including dense films and porous membranes, as well as different electroactive β-phase content, thermal and mechanical properties. The dielectric constant and piezoelectric d₃₃ coefficient for dense films reaches up to 16 at 1 kHz and 4 pC N⁻¹, respectively for PVDF-HFP with a fill density of 80 and a solvent evaporation temperature of 50 °C. Porous structures are developed for battery separator membranes in lithium-ion batteries, with a highest ionic conductivity value of 3.8 mS cm⁻¹ for the PVDF-HFP sample prepared with a fill density of 100 and a solvent evaporation temperature of 25 °C, the sample showing an excellent cycling performance. It is demonstrated that electroactive films and membranes can be prepared by direct-ink writing suitable for sensors/actuators and energy storage systems.     

Porous structures printed by fused deposition of granules processed from a novel polyamide/alumina-based system

Alumina ceramic porous structures were shaped by the fused deposition of alumina/polyamide 612 composite granules using an FDM 3D printer with a modified extruder to process granulated powder instead of a filament. The composite granules were prepared via thermally induced phase separation (TIPS). Firstly, in order to determine the proportion of polymer/solvent to be used in the TIPS process, different volume fractions of PA612 in dimethyl sulfoxide (DMSO) were studied (0.01 to 0.20), and the granules obtained were characterized by SEM, DSC, and Raman spectroscopy. Secondly, the addition of different ceramic loadings to the PA612/DMSO solution was studied with the aim of determining the amount to be used for preparing the composite granules by TIPS. In particular, the effect of the alumina content on the morphology and size of the obtained composite granules was studied. In addition, rheological properties (oscillatory and rotational tests) of the feed materials were studied. Finally, the printing conditions, including the nozzle temperature and nozzle diameter, and the extrusion process, were optimized in order to obtain porous structures with good quality. Alumina porous structures were successfully printed, debinded, and sintered. Adequate bonding between layers was achieved, and no defects at interfaces were detected.     

锆基块体非晶合金的力学性能研究进展

本文叙述了锆基块体非晶合金的制备方法，优异的性能，特别是对其力学性能研究领域的最新进展进行了综述。并与传统晶态合金作了适当的对比，锆基块体非晶合金具有优异的力学性能，如弹性比功、超塑性、断裂韧性等，此类合金的应用将不断拓宽。     

卡车纵梁及车厢边框冲孔线

介绍了轻、中型卡车纵梁及车厢边框加工新型数控冲孔生产线的结构、性能特点.生产线可实现卡车底盘纵梁及车厢边框的冲制,具有精度高、生产周期短、灵活性强等优点,并可大大减少生产环节的库存量.     

CIM技术在塑性成型工程的应用

本文根据国外ＣＩＭ技术发展的概况，针对塑性成形工程的特点，提出了塑性成形工程中实施ＣＩＭＳ技术应用和研究的几个重要的方向，同时，从系统集成的角度，指出基于知识集成的智能制造系统应是ＣＩＭＳ进一步发展的重点，最后，对这类系统建模的基本技术与方法进行了讨论。     

等离子熔积直接成形形状特性的基础研究

系统分析了熔积成形技术中影响成形形状特性的原因,研究了转移弧电流、扫描速度和起弧高度对成形精度的影响机理.实验表明,以上参数对等离子熔积直接成形形状特性的影响显著,对改善零件的成形精度起决定性的作用;通过优化成形工艺参数,焊道表面质量得到显著好转.     

逆向工程技术在复杂铸造模具制造中的应用

首先介绍了逆向工程技术与传统制造技术的区别,然后着重讨论利用逆向工程技术快速制造复杂铸造模具的过程及工艺路线,同时给出一些具体应用实例。最后得出与传统制造方法相比具有效率高、成本低、操作简单等优点的结论。     

甲醇汽油的技术进展及应用前景

介绍了甲醇汽油的界定，燃料特性，制法及其应用前景。讨论了甲醇汽油在使用中的安全问题。     

新型颗粒状活性染料

本文阐述了颗粒状活性染料的制造特点、制造技术和品质评价，并列举了典型的商品。