锌合金表带型材挤制的模具设计及数值模拟

为了得到自制锌合金的挤压型材，本文对挤压模具进行设计，设计方案有两种：单孔挤压模具和双孔挤压模具。通过数值模拟和实际挤压实验，实现了该锌合金的挤压成型，得到以下结论：两种不同模具挤压时，相同挤压速度下，锭子的温升值基本相等，最大挤压力相差不大；随着挤压速度的增大，挤压材料温度升高越显著，挤压所需的最大载荷增大；采用双孔挤压时，挤压更平稳，且挤压效率更高，所以采用双孔挤压方法进行挤压。     

铝材挤压模具的使用条件及其损坏原因分析

在挤压过程中，挤压工、模具的工作条件是十分繁重的。随着挤压产品品种的增加和规格大型化、形状复杂化、尺寸精密化、材料高强化以及大型的高比压挤压筒利新的挤压方法的不断出现，挤压工模具的工作条件变得更为恶劣了，对它们的要求也越来越高了。下面概括地分析一下铝合金挤压工模具的使用条件及其损坏原因：     

浅谈卧式挤压机挤压模具的结构改进设计

本文介绍了卧式挤压机挤压模具的结构改进设计，并对各种结构设计的优缺点进行了分析、总纳，改进后的模具结构可降低成本、提高质最．具有显著的经济效益。     

铸造法对运动器材用镁合金疲劳性能研究

分别运用传统铸造法和挤压铸造法制备用于运动器材中的镁合金，并对其进行疲劳性能测试，通过测试结果可以得知：运用挤压铸造法制备的镁合金疲劳性能要远高于运用传统铸造法制备的镁合金，应用于运动器材之中，可增强其韧性，延长使用寿命。     

真空挤压成型机挤压筒的折弯成型

本文指出了真空挤压成型机挤压筒的传统制造方法（铸造成型）的弊病——挤压筒两端面的形状位置精度差（如：同轴度误差大）、内腔工作表面粗糙及凹凸不平等，提出了消除此弊病的有效途径是采用板料折弯成型后再焊接成挤压筒的制造方法；详细地论述了折弯板料展开图的求解、板料折弯成型及焊接加工的方法。它具有生产工艺简单、无需胎模具、节约原材料、生产成本低廉、易于保证挤压筒两端面的形状位置精度及其内腔工作表面平整光洁等优点，能最大限度地减小陶瓷泥料挤出成型时的分层及摩擦发热等缺陷，优化了陶瓷泥料的挤出成型工艺。     

600孔／in^2蜂窝陶瓷载体挤压成形模具

分析了蜂窝陶瓷载体挤压模具的通常结构用于高孔密度载体生产中存在的问题,并研究和设计出一种新的结构,成功地挤压出600孔／in^2的蜂窝陶瓷载体。     

铝挤压模的失效形式及提高寿命的途径

介绍了铝挤压模磨损、开裂、变形的三种主要失效形式，分析了失效发生的根本原因。从模具设计、模具材料、热处理和表面处理、模具制造加工、模具的工作条件和环境五方面叙述了提高铝挤压模具寿命的途径。     

600孔/in~2蜂窝陶瓷载体挤压成形模具

分析了蜂窝陶瓷载体挤压模具的通常结构用于高孔密度载体生产中存在的问题 ,并研究和设计出一种新的结构 ,成功地挤压出 60 0孔 in2 的蜂窝陶瓷载体。     

钛及钛合金型材模拟等温挤压速度控制系统

钛及钛合金型材是重要的航空航天结构材料,等温挤压对提高钛及钛合金型材的质量与产量均具有重大影响,关键是挤压过程变形温度和挤压速度控制。针对25MN钛及钛合金型材挤压机,研制了钛型材模拟等温挤压速度控制系统。该系统由红外测温仪、研华工控机、S7-1500PLC、执行控制装置构成,采用红外测温仪对挤压机模具口进行实时测温,工控机和PLC进行等温挤压速度曲线计算及温度挤压速度闭环控制,实现了对挤压过程变形温度和挤压速度的准确控制。生产运行表明,该系统对提高钛及钛合金挤压型材质量和挤压生产效率以及稳定挤压生产工艺具有重要作用,在钛及钛合金加工领域具有典型应用价值。     

聚氯乙烯内挤压挤出模具的设计

传统的外挤压挤出模具应用非常广泛,经过改进设计,采用内挤压挤出模具,不但小巧玲珑,使用较小的压缩比,可减小制品的内应力,获得较高的外观及内在质量;相对于机筒,机头的反作用力小,有利于加工成型;成型段的尺寸可适当减少,有利于高速挤出成型等。     

Three Screw Extruder

电子、汽车、电机、电器、仪器、仪表、家电、通讯和军工等产品中，60％～80％的零部件，都要依靠模具成型。用模具成型的制件所表现出来的高精度、高复杂性、高一致性、高生产率和低消耗，是其他加工制造方法所无法比拟的。模具在很大程度上决定着产品的质量、效益和开发能力。     

挤压铸造5035 铝镁合金阳极氧化染黑色后白点故障分析

挤压铸造5035铝镁合金在硫酸阳极氧化以及在酸性染色溶液染黑色后表面出现白点,影响产品的外观。采用能谱仪分析了5035铝镁合金基体及阳极氧化膜的元素成分,并采用金相显微镜观察基体表面形貌及阳极氧化膜的表面与截面形貌,结合基材的挤压铸造过程进行分析,得出产生白点的可能原因是挤压铸造时产生的缩孔。提出了挤压铸造及阳极氧化工艺的改进措施。     

固体氧化物燃料电池的制备工艺

介绍了不同形状和类型的固体氧化物燃料电池的各结构部件的常用制备工艺方法,包括:用于平板式支撑体制备的干压法和流延成型法,制备平板膜的涂刷、丝网印刷、离心沉积和旋涂法,管式支撑体制备的注浆成型、挤出成型、热压注、浸涂、凝胶铸模和相转换法,以及用于管式膜制备的涂刷、浸涂、料浆喷涂、电化学气相沉积和热喷涂法。针对每种工艺方法,介绍了其原理和基本工艺操作流程及其在固体氧化物燃料电池制备中的应用,讨论了工艺影响因素。     

Extruded high-strength solid materials based on magnesium with zinc,yttrium, and cerium additives

Magnesium (the lightest structural material) is suitable for manufacturing movable parts of vehicles and finds wide application in car and aerospace engineering. Magnesium alloys produced by conventional casting have defects and large-sized grains and exhibit undesirable mechanical properties. The desirable properties of magnesium alloys can be achieved by improving their microstructure. This paper reports on the results of investigations of high-strength products (8–50 mm in diameter) prepared by extrusion from rapidly solidified ribbons of the Mg-6Zn-1.5Y-0.5Ce alloy (hereafter, numbers in the compositions indicate the elemental content in wt %). The tensile strengths of the products are equal to 450–520 MPa, and their elongation (E, %) is limited. The microstructure of the materials at each stage of treatment is examined using optical microscopy or scanning electron microscopy with energy-dispersive X-ray analysis and X-ray diffraction. It is demonstrated that Mg-Zn-Y-Ce alloys with a fine-grained structure can be prepared by both conventional casting and rapid solidification. The mean sizes of magnesium solid-solution grains and supersaturated magnesium solid-solution grains are equal to 45 and 5 µm for alloys produced by casting and rapid solidification, respectively. The formation of a fine-grained structure is predominantly associated with the remelting of solidified dendrites. In this process, cerium plays a decisive role. The theoretically expected tensile yield strength of the Mg-6Zn-1.5Y-0.5Ce high-strength solid materials produced by extrusion should be higher for materials with a fine-grained structure. It is shown that the discrepancy between the theoretical and experimental results is caused by the extrusion defects. The conclusion is drawn that the strength of the materials extruded from rapidly solidified ribbons depends on their microstructure and extrusion conditions.Original Russian Text Copyright © 2005 by Fizika i Khimiya Stekla, Guo, Shechtman.     

聚丙烯硬弹性膜的挤出流延工艺及拉伸成孔性

以某进口均聚聚丙烯(PP)(PP1)为原料,通过挤出流延工艺制备了PP1硬弹性膜并在130℃下对其进行热处理,研究了挤出温度、流延辊转速及温度、热处理温度和时间等工艺参数对PP1硬弹性膜弹性回复率的影响,得到了最佳工艺条件,即挤出温度为195℃、流延辊温度及转速分别为90℃,26 r/min,热处理温度和时间分别为145℃,30 min。将该工艺应用于分子量及其分布与PP1基本相似的国产PP(PP2),发现由此工艺制备的PP2硬弹性膜的弹性回复率可达94.6%,与PP1硬弹性膜相差不大。通过冷热单向拉伸将PP1和PP2硬弹性膜制备成微孔膜,发现两者具有相似且优异的微孔结构。在此基础上,通过扫描电子显微镜研究了冷热拉伸工艺参数对PP2微孔膜拉伸成孔性的影响。结果表明,当冷拉伸倍数为15%,热拉伸倍数为100%,冷热拉伸速率均为50 mm/min时,制备的PP2微孔膜形成了完整规则的多孔结构。     

Studies on the theory of single screw plasticating extrusion. Part I: A new experimental method for extrusion

An extruder specially designed for the study of the single-screw plasticating extrusion process was constructed. Its barrel is equipped with glass windows which are located on both sides of it so that the full process of plasticating extrusion, solid conveying, melting, and melt conveying, can be clearly observed and recorded with photos and video recordings through the transparent windows. The solid profile X/W, the velocity of the solid bed V_sz, the forming positions of the upper melt film and the melt pool, and the position at which the break-up of solid bed occurs, was easily determined with good accuracy. Many dynamic characters of the plasticating extrusion, such as the non-plug solid conveying, the process of the break-up of the solid bed and the disappearance of the, broken pieces of solid, were also observed in the experiments.     

固相水合法与挤压法制取重质纯碱的技术比较及经济评价

对鸿鹤化工总厂新建重质纯碱装置将采用的工艺路线进行分析；介绍挤压法和固相水合法流程和装置特点；对两种工艺路线进行技术比较和经济评价，指出从流程、设备、技术、操作、管理等因素衡量，挤压法均优于固相水合法，新建重质纯碱装置采用挤压法是可行的。     

Microcellular extrusion of PLA utilizing solid‐state nucleation in the gas‐saturated pellet extrusion process

In this study, we explore the use of solid‐state nucleation in polymer pellets as a means to create microcellular PLA foams in extrusion. This is achieved by using gas‐saturated PLA pellets as input to the extruder. Foam density, bubble size, and bubble density is reported and compared with microcellular foams created in the gas‐injection extrusion process. PLA pellet gas concentrations between 17 and 29 mg CO₂/g PLA was found to produce quality microcellular foams in this process. Gas concentrations within this range were achieved by varying methods that included partial saturation, desorption from full saturation, and blending saturated with unsaturated pellets. This gas concentration window that produced microcellular foams was found to be independent of the saturation and desorption process used to achieve the desired concentration. We further compare the pressure drop and pressure drop rate of the gas‐saturated pellet extrusion process showing that similar foams can be produced at pressures orders of magnitude lower than the alternative gas‐injection extrusion processes. Investigations into extrusion pressures support the hypothesis that the gas‐saturated pellet extrusion process utilizes solid‐state nucleation in the feed section of the extruder to achieve high bubble density foams. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

外墙装饰挂板高速挤出模具设计

提出了一种外墙装饰挂板高速挤出模具设计方法,通过在定型板前端增加变形板装置、改进定型板冷却水路结构,实现高速挤出生产,生产速度由原来的3 n/min左右提高到10 n/min.     

实心注浆成型中开裂缺陷的分析及解决方法

对实心注浆过程中产生的开裂缺陷，分别从泥料配方、泥浆性能、模型制作以及人为因素等方面进行分析，初步提出一些解决方法，较好地解决实心注浆过程中坯体开裂缺陷的产生，从而提高实心注浆坯体质量。