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1.
镁合金半固态压铸触变成形技术的研究与进展   总被引:3,自引:0,他引:3  
介绍了镁合金半固态触变成形技术中的三个关键技术:非枝晶组织半固态浆料的制备、坯料的二次加热、半固态触变压铸成形.并综述了镁合金半固态压铸触变成形技术的研究现状和发展前景.  相似文献   

2.
金属半固态成形技术的研究进展   总被引:2,自引:0,他引:2  
概述了半固态金属成形技术近年来的研究进展;阐述了半固态触变成形技术中的三个关键技术:非枝晶组织半固态浆料的制备,坯料的二次加热,半固态触变压铸成形;并分析了其发展方向与研究趋势.  相似文献   

3.
《铸造技术》2007,28(B07):50-50
日本素形材登载了菊池政男撰写的文章,针对目前引人注目的半固态压铸技术,沿其发展过程介绍了最新的研究与开发动向。半固态压铸可分为流变压铸和触变压铸2类。半固态压铸的特点有减少缩松、提高强度、凝固潜热小、浇注温度低、可提高模具寿命等。对比了流变压铸、触变压铸、挤压、金属型铸造的A357合金的抗拉强度、伸长率及组织,叙述了半固态压铸技术的历史发展变迁,  相似文献   

4.
A356半固态触变充型与压铸充型过程模拟比较   总被引:5,自引:5,他引:0  
利用商业软件Flow-3D,模拟了A356合金半固态触变压铸和普通压铸的充型流动过程。模拟结果表明:相同模具结构中的半固态压铸和普通压铸充型过程,半固态流动平稳,普通压铸由于湍流流动,因而容易出现气孔、卷气夹杂等缺陷。半固态触变压铸和普通压铸具有相同的流动通道。  相似文献   

5.
Al-Mg-Si合金半固态触变成形研究   总被引:2,自引:2,他引:0  
以水泵盖为目标零件,在自行建立的半固态触变成形试验线上使用A357合金和新开发的半固态专用铝合金Al-6Si-2Mg进行了半固态触变压铸试验研究.对这两种合金在半固态坯料制备、二次加热及半固态压铸中的显微组织及工艺性进行了比较.结果表明,Al-6Si-2Mg合金在触变成形过程中均表现出更好的工艺可控性,其半固态压铸件热处理后的性能为σb=335MPa,σs=305MPa,δ5=3%,强度高于A357,伸长率与铸态A357合金相当.试验最终获得了充型完好、性能优异、组织均匀的半固态压铸件.  相似文献   

6.
详细介绍了半固态A356铝合金触变压铸、制备工艺的参数设计、合金组织性能状况、合金应用以及国内外的发展情况,分析了半固态铸造成型技术在我国的发展前景,展望了半固态金属成型在我国应用的前景及意义。  相似文献   

7.
半固态压铸技术研究发展现状   总被引:1,自引:0,他引:1  
回顾了半固态压铸技术的发展历史,介绍了其国内外研究现状,包括半固态金属触变压铸和流变压铸工艺,重点介绍了铝合金及镁合金半固态压铸技术研究及应用现状,讨论了半固态压铸成形技术存在的问题及发展策略.  相似文献   

8.
汽车用铝合金半固态零件触变压铸工艺研究   总被引:1,自引:1,他引:0  
针对半固态触变压铸工艺特点,对国产J1128卧式冷室普通液态压铸机的压射系统和模具系统进行了结构改进,对压铸工艺参数进行了优化选择,并采用半固态专用铝合金AlSi6Mg2和商用铝合金A357开展了大量半固态触变压铸试验研究.结果显示:半固态触变压铸工艺与普通液态压铸有很大的不同,在压射室和模具预热温度分别为100℃和250℃,低压压力为4.0MPa,射料二速工作压力为12MPa,增压压力为20MPa,快压射速度为1.4m/s条件下可获得冲型完好的汽车用铝合金半固态零件.  相似文献   

9.
汽车用铝合金半固态零件触变压铸工艺研究   总被引:3,自引:3,他引:0  
针对半固态触变压铸工艺特点,对国产J1128卧式冷室普通液态压铸机的压射系统和模具系统进行了结构改进,对压铸工艺参数进行了优化选择,并采用半固态专用铝合金AlSi6Mg2和商用铝合金A357开展了半固态触变压铸试验研究.结果表明: 半固态触变压铸工艺与普通液态压铸有很大的不同,在压射室和模具预热温度分别为100 ℃和250 ℃,低压压力为4.0 MPa,射料二速工作压力为12 MPa,增压压力为20 MPa,快压射速度为1.4 m/s条件下可获得充型完好的汽车用铝合金半固态零件.  相似文献   

10.
AZ91D镁合金半固态触变成形压铸工艺   总被引:3,自引:0,他引:3  
采用等温热处理对AZ91D镁合金进行非枝晶化,研究半固态镁合金的触变压铸工艺,得到性能良好的触变压铸镁合金试件。通过改变压力和压射速度等工艺参数,发现其抗拉强度和伸长率都随着压力或速度的上升而增加,当增压压力为35MPa和压射速度为4.5m/s时,其抗拉强度达到最大,为237.5MPa,伸长率为4.8%。通过组织分析认为,半固态触变压铸对晶粒细化效果明显,这与固相颗粒在充型过程中的二次破碎,液相喷射分散后凝固具有直接的关系。  相似文献   

11.
Alloys with an equiaxed microstructure exhibit significantly lower flow resistance in the semisolid state than alloys with a dendritic microstructure. Their thixotropic behavior (solidlike in the unperturbed state and liquidlike during shearing) has been the basis for a thixoforming process. It is accepted today that thixoforming is a new net-shaped manufacturing technology in which the billet is heated to the semisolid state with coexisting solid-liquid phases. The thixoforming process has some industrial advantages, such as the successful fabrication of high-quality components with fewer inner defects, suitable for less machining, high productivity comparable to high-pressure die casting, and being an energy-saving system without the conventional melting process. It consists of inductive coil design, a billet reheating process, billet handling, filling into the die cavity, and solidification of the thixoformed part. This work presents an overview of all the detailed stages in the thixoforming process to manufacture the net-shaped product with good mechanical properties. An air compressor part with high strength has been fabricated by the thixoforming process.  相似文献   

12.
The 6061 semi-solid aluminium alloy feedstocks prepared by near-liquidus casting were compressed in semi-solid state by means of Gleeble-3500 thermal-mechanical simulator. The relationship between the true stress and the true strain at different temperatures and strain rates was studied with the deformation degree of 70%. The microstructures during the deformation process were characterized. The deformation mechanism and thixo-forming properties of the semi-solid alloys were analyzed. The results show that the homogeneous and non-dendrite microstructures of semi-solid 6061Al alloy manufactured by near-liquidus casting technology could be transformed into semi-solid state with the microstructure suitable for thixo-forming which are composed of near-spherical grains and liquid phase with eutectic composition through reheating process. The deformation temperature and strain rate affect the peak stress significantly rather than steady flow stress. The resistance to deformation in semi-solid state decreases with the increase of the deformation temperature and decrease of the strain rate. At steady thixotropic deformation stage, the thixotropic property is uniform, and the main deformation mechanism is the rotating or sliding between the solid particles and the plastic deformation of the solid particles.  相似文献   

13.
AlSi8Cu3Fe alloy is a general purpose die casting alloy widely used to manufacture automotive parts. Forming of this alloy in the semi-solid state could largely eliminate problems inherent in die casting process and thus offers a number of advantages. Low superheat casting was employed in the present work to produce non-dendritic AlSi8Cu3Fe alloy feedstock. The ingots thus obtained were thixoformed in a laboratory press after they were held at 570 °C for 5 min, yielding a microstructure with predominantly α-Al globules and interglobular Si particles. The thixoformed parts attain hardness values as high as 125 HB after T6 heat treatment, implying a considerable age hardening potential. However, with a reheating temperature range of 568–572 °C, thixoforming of AlSi8Cu3Fe alloy components under industrial conditions may be challenging.  相似文献   

14.
任建民  周世旭 《轧钢》1998,(5):51-54
通过多次技术改造,发现了生产热轧带肋钢筋套用传统的孔型设计参数存在的问题,因而对连铸方坯在箱形孔型、方轧件在平椭圆孔型中宽展系数的选取进行了研究,并介绍了在连铸坯一火成材改造中,通过改进孔型系统改善了咬入状态,使轧制更加稳定。  相似文献   

15.
压铸模CAD/CAE/CAM的现状与发展对策   总被引:4,自引:0,他引:4  
陈光明 《模具技术》2003,(5):45-49,55
分析了我国压铸模设计与制造的现状、存在的问题,介绍了国内外压铸模CAD/CAE/CAM技术的研究进展,根据我国压铸模CAD/CAE/CAM技术研究与开发存在的问题提出了加快发展我国压铸模CAD/CAE/CAM技术对策。  相似文献   

16.
高熔点合金半固态压铸模研究   总被引:2,自引:0,他引:2  
黄勇 《模具工业》2003,(4):44-47
通过杠杆的半固态压铸模设计 ,提出了黑色金属半固态压铸模的设计要点 ,研究了设计中涉及的压铸机选择、压室设计、成型部分材料选择、浇注系统设计、模具加热冷却系统设计等关键技术问题 ,得出了解决问题的方法  相似文献   

17.
Semisolid die casting of thixotropic Al-7Si-0.3Mg alloy has been carried out using a vertical-injection squeeze casting machine. The flow of the billet surface layer during casting was determined by X-ray examination of embedded markers. Tensile properties of the castings were then evaluated and metallographic observations were made. The original billet surface layer was found to be largely confined to the surface layer in the biscuit, except for the top of the billet surface, which flowed to the upper surface of the casting. As a consequence, the incidence of oxide inclusions within the casting was very low, leading to high elongation values with low scatter. Significantly lower strength and higher elongation values were observed in the biscuit. This effect was attributed to there being a significantly lower concentration of the solute elements in the biscuit compared to the casting.  相似文献   

18.
通过黑色金属零件杠杆的半固态压铸模设计,提出了黑色金属半固态压铸模的设计要点,研究了设计中涉及的压铸机选择,压室的设计,成形部分材料的选择,浇注系统的设计,模具加热,冷却系统的设计等关键技术问题,得出了解决问题的方法。  相似文献   

19.
To fabricate electronic packaging shell of copper-matrix composite with characteristics of high thermal conductivity and low thermal expansion coefficient, semisolid forming technology, and powder metallurgy was combined. Conventional mechanical mixing of Cu and SiC could have insufficient wettability, and a new method of semisolid processing was introduced for billets preparation. The SiC/Cu composites were first prepared by PM, and then, semisolid reheating was performed for the successive semisolid forging. Composite billets with SiC 35% volume fraction were compacted and sintered pressurelessly, microstructure analysis showed that the composites prepared by PM had high density, and the combination between SiC particles and Cu-alloy was good. Semisolid reheating was the crucial factor in determining the microstructure and thixotropic property of the billet. An optimised reheating strategy was proposed: temperature 1,025 °C and holding time 5 min.  相似文献   

20.
为解决长锥筒形铸件所需抽芯距离过长和脱模困难的问题,设计了带有特殊抽芯-推出机构的长锥形套筒压铸模,分析了套筒的工艺特性,详细论述了压铸模的结构设计和工作过程。该模具采用斜销-浮动滑块机构,使抽芯的滑块不仅可沿抽芯方向移动,而且可沿推件方向浮动。先由斜销-浮动滑块机构做短距离抽芯,然后推杆沿推件方向推动滑块和型芯,将铸件推离动模。从而大大减小了所需开模行程,降低了设备成本,提高了生产效率。模具结构紧凑,工作可靠,铸件无推痕,成型铸件质量好。  相似文献   

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