国内外铝挤压工模具技术的发展概况与创新亮点

论述了工模具在铝合金挤压生产中的重要作用与特殊地位;介绍了铝挤压工模具技术的主要内容;着重分析了国内外挤压工模具设计制造水平及创新亮点、铝挤压工模具的使用、修理、氮化技术及现代化管理。     

国内外铝挤压工模具技术

本文简略地论述了工模具在铝合金挤压生产中的重要作用与特殊地位:介绍了铝挤压工模具技术的主要内容;着重分析了国内外挤压工模具设计制造水平及创新亮点,以及铝挤压工模具的使用、修理、氮化技术及现代化管理工具。     

现代铝合金挤压工业及技术发展概况与趋势

简明扼要地介绍了现代铝合金挤压工业及其生产技术的发展现状与趋势，重点论述了铝及铝合金挤压生产及管、棒、型、线材的挤压技术、热处理和精整矫直等方面的发展特点、水平、产品品种、工艺技术、工模具技术及设备状况。     

镁及镁合金挤压模具的设计特点

论述了镁及镁合金挤压工模具的特点及与铝及铝合金挤压工模具的异同,分别介绍了镁及镁合金棒材模、无缝管材模、型材模及平面组合模的设计要点并举例说明,对指导生产实践有一定的价值。     

几种典型铝挤压型材模具的结构设计方案

现代铝型材企业中,模具设计的合理性直接影响到挤压生产成本和效率以及产品交货周期。随着铝合金型材向大型化、复杂化、精密化、多用途方向发展,对挤压工模具提出了越来越高的要求。因此,提高模具结构设计方案的合理性成了整个铝挤压模具行业的重中之重。通过对几种较为典型的铝挤压模具的设计方案进行对比和剖析,指出优缺点,并提出正确有效的修正方法。     

铝合金挤压工业及技术和装备发展现状与趋势

简明扼要地介绍了铝及铝合金挤压产业及其生产技术与主要工艺装备的发展现状与趋势,重点论述了铝及铝合金挤压生产及管、棒、型、线材的挤压技术、热处理和精整矫直等方面的发展特点、水平、产品品种、工艺技术、工模具技术及设备状况。由于科学技术的进步,经济的高速发展,对铝及铝合金管、棒、型、线材产品提出了越来越高的要求,近几十年来,国内外的生产技术与装备也获了长足的发展并达到了相当高的水平。我国的挤压工业与技术也有了极大的进步,但与国际先进水平仍有一定的差距。     

现代铝挤压工业的发展特点及挤压技术发展新动向

在简要地介绍了现代铝挤压工业的发展特点之后,重点论述了铝及铝合金挤压生产的发展水平、产品品种、工艺技术、工模具技术及设备技术的新动向。由于科学技术的进步,经济的高速发展与人民生活水平的不断提高,对铝及铝合金管、棒、型、线材产品提出了越来越高的要求,近几十年来,国内外生产技术与装备也获得了长足的发展并达到了相当高的水平。我国的挤压工业与技术也有了极大的进步,但与国际先进水平仍有一定的差距。     

汽车用6005A铝合金型材组织及性能提升技术研究

通过对6005A合金铸锭均匀化制度和挤压工模具结构进行调整,来改善挤压制品的晶粒组织结构,进而达到提高6005A铝合金汽车梁挤压制品的力学性能及稳定性的目的.试验结果表明,适当调整铸锭均匀化制度以及减少模具工作带长度,对减轻挤压制品再结晶层厚度有明显作用,即当铸锭均匀化制度调整到510℃、保温6 h,降低模具工作带长度...     

挤压温度对铝合金材料组织和性能的影响研究

铝合金材料因其密度较低、热导性强以及高比强被广泛应用于各个行业,通过实验分析铸锭坯料温度、挤压筒温度及工模具温度对铝合金材料组织和性能的影响。实验结果表明,铝合金材料组织比较细小且分布均匀,当挤压温度超过一定范围时,铝合金材料发生明显改变,由原来的韧性断裂方式变成韧性与脆性共存的混合断裂方式。     

基于HyperXtrude铝型材挤压模具设计和模拟分析

本文针对某公司生产的6063铝合金复杂截面工业型材,在分析铝合金型材挤压分流模的各结构要素的基础上,设计了分流挤压模并对模具强度进行了校核;运用Pro/E绘图软件,建立了模具的三维仿真模型;基于HyperXtrude有限元分析软件平台,对该型材的挤压过程进行了模拟仿真分析,获得了挤压过程中型材和模具的温度、应力、变形分布;通过对模拟结果的分析,预测了挤压时可能产生的弯曲、翘曲等缺陷,并对分流孔、工作带以及工艺等进行了优化,使挤压时金属流动更加均匀。     

一种高强度低温韧性钢的研发

本次结合我公司的工装条件，研发了一种高强度低温韧性钢，为同行业的钢种研发提供参考。     

我国粉末冶金模具用钢的现状和发展

本文介绍了国外粉末冶金模具的用材情况 ,评述了我国粉末冶金行业模具材料的使用现状和发展 ,提出了推广应用新型模具用钢的建议。     

Influence of Small Die Width on Filling and Compacting Densities

Abstract

Experiments conducted to try to establish the influence of small die openings on the actual filling density are reported. A special apparatus, consisting of rectangular dies of various widths, has been utilized with copper and mixed elemental bronze powders. The results show that filling densities decrease with decreasing die opening. The angle between sense of motion in filling and main die axis also influences the filling density, through rebounds during powder fall; these rebounds play a positive role. The changing quantity of powder entering various dies can be explained by assuming that a boundary layer is present on the die surfaces. This boundary layer, with density tending to zero when approaching the walls from the bulk of the powder, is dependent on grain shape and sieve analysis. A simple theory, including a hydraulic radius of ‘compacting’ area, has been proposed and the corresponding formulae for different die geometries derived. The theoretical lines are in good agreement with the results of experimental tests. The boundary layer widths depend on powder type, lubricant, and angle between filling motion and main die axis. This work enables the design engineers involved in tooling to estimate the possible density excursions on PM parts of varying thicknesses, while the require- ment of completely uniform density necessarily demands ‘tricks’ with tools, filling devices, and common practice. PM/0448     

Ni-based superalloy as a potential tool material for thixoforming of steels

Abstract

Semisolid processing, already a well established manufacturing route for the production of intricate, thin walled aluminium and magnesium parts with mechanical properties as good as forged grades, faces a major challenge in the case of steels. The tool materials must withstand complex load profiles and relatively higher forming temperatures for thousands of forming cycles for this near-net shape process to be attractive for steels on an industrial scale. The potential of a Ni-based superalloy, Inconel 617, reported to exhibit superior thermal fatigue resistance in demanding tooling applications, was investigated. The response to thermal cycling of this alloy at high temperatures was compared with that of X38CrMoV5 hot work tool steel widely used in the manufacture of conventional forging dies. The favourable thermophysical properties of the latter were completely negated by its limited temper resistance, while the Inconel 617 alloy responded to thermal cycling by the usual heat cracking mechanism.     

A CrNiCo Alloy as a Potential Tool Material in Semi‐solid Processing of Steels

Semisolid processing of aluminium and magnesium alloys has matured to become a well established manufacturing route for the production of intricate, thin‐walled parts with mechanical properties as good as forged grades. However, this innovative forming technology faces a major challenge in the case of steels. The tool materials must withstand the complex load profile and relatively higher forming temperatures which promote chemical interaction with steel slurries. Thixoforming tools ought to last thousands of forming cycles for industrial application to be attractive. Hot work tool steel dies proved to be entirely inadequate when thixoforming steels. In spite of extensive research on tool materials for the semisolid processing of steels, there is yet no material to fulfil this critical role. The present work was undertaken to explore the potential of a novel CrNiCo alloy as the tooling material in semisolid processing of steel.     

同步器齿毂成形模结构及其应用

为了生产高质量的汽车高速器同频器齿毂，合理设计与选择成形模结构尤为重要。本文介绍了几种成形模结构实例，特别叙述了近几年来国际上最新的粉末成形方法－－轮廓装粉成形法，并对它们在不同条件下的应用进行了探讨。     

Response to thermal cycling of tool materials under steel thixoforming conditions

Abstract

The principal failure mechanism of steel thixoforming dies is thermal fatigue owing to forging pressures much lower than those encountered in conventional forging. This makes a properly designed thermal fatigue test the best method to identify suitable tooling materials for the steel thixoforming environment. Samples of X32CrMoV33 hot work tool steel and CrNiCo alloy were cycled thermally between 450 and 750°C, every 60 s for a total of 1500 cycles. While the thermal stresses generated at the surfaces of the two materials were very similar, their responses to thermal cycling were markedly different. The X32CrMoV33 steel was softened by nearly 40% after only 400 cycles, raising serious concerns over its temper resistance under steel thixoforming conditions. The extensive oxidation and subsequent spalling of oxide scales suffered by the X32CrMoV33 hot work tool steel is also a major shortcoming. The performance of the CrNiCo alloy, on the other hand, was judged to be satisfactory with a much thinner heat affected zone and a much better oxidation resistance. Lack of evidence for heat checking in this alloy after 1500 cycles is an encouraging sign.     

国内热作模具材料发展现状

本文简要介绍了国内热作模具材料的市场现状和现有主要热作模具材料类型,分析了国内热作模具材料所存在问题,并结合国外先进水平指出国内热作模具材料的发展趋势.