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1.
国内外铝挤压工模具技术的发展概况与创新亮点   总被引:6,自引:4,他引:2  
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。  相似文献   

2.
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。  相似文献   

3.
现代铝合金挤压工业及技术发展概况与趋势   总被引:1,自引:0,他引:1  
刘静安 《铝加工》2009,(6):29-33
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。  相似文献   

4.
刘静安 《铝加工》2011,(2):36-39
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。  相似文献   

5.
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。  相似文献   

6.
现代铝挤压工业的发展特点及挤压技术发展新动向   总被引:1,自引:1,他引:0  
何树权  刘静安  何伟洪 《铝加工》2010,(6):16-21,25
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。  相似文献   

7.
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。  相似文献   

8.
吕兆勇 《铝加工》2006,(5):31-33
从6063铝合金铸锭、挤压工艺条件、模具、金属的不均匀变形等方面分析型材挤压时发生“堵模”现象的原因;提出了其防止措施。  相似文献   

9.
刘静安 《铝加工》2000,23(6):1-8
3 在金属挤压成形过程的数值模拟与物理模拟方面取得的主要成果3.1 铝合金挤压时温升有限元分析利用工程计算法可计算出热能的发生源和发生量,用微分方程式和有限元法可计算出发生热的热传导。基于上述原理建立了数学模型,选择和处理边界条件、单元及其划分,围绕坯料、挤压筒、模具等,计算和确定了坯料温升的热源、坯料内的热传导、挤压筒壁周围发热产生的温升和模孔周围发热引起的温升、向模具和挤压筒扩散的热、挤压温升与挤压速度的关系问题,为合理设计挤压工艺和挤压工模具提供了依据。3.2 挤压模内温度场的有限元分析在铝型材热挤压…  相似文献   

10.
为了加速我国地铁与高速列车车辆用大型铝合金型材国产化的进程,全面了解和剖析工业发达国家大断面特种铝合金型材的挤压技术与装备水平,并为我厂80MN挤压机本体及配套设备改造作好前期准备工作,同时全面了解法铝板、带、箔生产技术情况,西南铝加工厂组成考察团,于1998年5月31日到6月18日访问了德国和法国的大断面铝合金挤压型材生产厂和应用厂及设备和工模具制造厂,以及法铝的中厚板、罐体材料和铝箔生产厂。不论是在德国,还是在法国,考察团所到之处,都受到了热情而有准备的接  相似文献   

11.
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。  相似文献   

12.
我国粉末冶金模具用钢的现状和发展   总被引:1,自引:1,他引:0  
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。  相似文献   

13.
《粉末冶金学》2013,56(4):261-266
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  相似文献   

14.
《钢铁冶炼》2013,40(7):555-560
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.  相似文献   

15.
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.  相似文献   

16.
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。  相似文献   

17.
《钢铁冶炼》2013,40(1):41-46
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.  相似文献   

18.
There is a growing demand for single-use disposable polymer devices with features at submicron scales. This requires resilient tooling which can be patterned to scales of the order of hundreds of nanometers. The requisite topology can be imparted to silicon, but it is too brittle to be of use in a die to mold thousands of plastic parts. The polycrystalline nature of tool steel means that it cannot be patterned with submicron detail. Some bulk amorphous alloys have the requisite mechanical properties to be viable as materials for such dies, and can be patterned—e.g., via embossing as a supercooled liquid into MEMS silicon or using focused ion beam (FIB)—with submicron features which may persevere over many thousands of molding cycles. The composition of the amorphous alloy must be carefully selected to suit the particular molding application (polymer/process). The state-of-the-art methodology is presented, along with results of our recent experimental investigations.  相似文献   

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