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变形铝合金挤压铸造 总被引:3,自引:2,他引:1
齐丕骧 《特种铸造及有色合金》2008,28(10)
变形铝合金材料(如7A04、2A01、6061等)均可以用直接挤压铸造工艺进行生产,并可接近达到同种锻件的力学性能水平,但直接挤压铸造在铸件形状、表面状况等方面会受到某些局限.用普通间接挤压铸造,其铸件会有很高的裂纹倾向,以致于复杂薄壁件难以生产.为此采用双重挤压铸造等工艺,不失为一种可取的选择. 相似文献
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铝合金双重挤压铸造补缩位置和补缩力的确定 总被引:2,自引:1,他引:1
以某铝合金汽车轮毂为研究对象,运用铸造有限元分析软件,对其进行了挤压铸造数值模拟。研究了填充和凝固过程中温度场的分布,预测了在此过程出现的缩孔、缩松缺陷位置。模拟结果显示,轮毂中心部位容易产生缩孔、缩松,因此将双重挤压铸造补缩位置设置在轮毂中心部位。计算补缩力时采用屈服准则分析并得出补缩力的经验公式,然后对轮毂进行双重挤压模拟,最终确定补缩力的大小。 相似文献
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挤压铸造生产锌基合金蜗轮新工艺研究 总被引:2,自引:2,他引:0
介绍了BW-120/10泥浆泵蜗轮复合体挤压铸造一次成形工艺,并对制品的金相组织及力学性能进行了分析测试。试验表明:用挤压铸造工艺取代原有的旧工艺可明显提高制品性能,降低成本,提高生产率,具有明显的经济效益和较大的推广价值。 相似文献
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挤压铸造ZA27合金 总被引:10,自引:2,他引:8
针对ZA27合金在常规铸造下易出现缩松、偏析等缺陷的特点、研究了该合金的挤压铸造工艺。系统试验分析了挤压工艺参数与ZA27合金性能之间的关系。研究表明:挤压铸造能明显提高ZA27合金的密度和力学性能,通过工艺参数的控制,既可获得高强度,又可获得高塑性的ZA合金。 相似文献
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挤压铸件优质化技术进展 总被引:3,自引:5,他引:3
概述了国内外在生产高致密度、高力学性能、高耐磨铝合金挤压铸件,以及大型复杂铝合金挤压铸件方面的新技术,对于挤压厚大的复杂零件,可使用局部补压技术消除厚大处的缩孔缩松。对于高致密度高力学性能零件,挤压时采用真空液态挤压铸造系统,可生产高质量的挤压件;对于耐磨损零件一般采用高硅铝合金和陶瓷增强铝基复合材料。对复杂内腔的零件,可用可溶性盐芯和易溃散砂芯解决难成型问题。挤压铸造在实践中得到发展。 相似文献
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挤压铸造近年来发展很快,填充式间接挤压铸造法尤为突出.在国外,适合这种挤压铸造方法的挤压铸造机通常有VV、HV和HH 3种型式;国内领先开发的一种全卧式HH型挤压铸造机,具有压铸与挤压铸造双功能的特点.LK/HH挤压铸造机依靠一种自行开发的慢压射技术,保证了压射冲头沿水平方向向前推送金属液使之充满整个压室,从而避免了压室内上部气体卷入金属液内,是解决铸件内部孔隙(或孔洞)问题的一个有效途径. 相似文献
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介绍挤压压铸技术的特性,提出将普通压铸机改造为挤压压铸机,应用挤压压铸工艺的思路,以挤压压铸对重力铸造、低压铸造、差压铸造以及其他特种铸造成形工艺的替代,满足中国汽车、摩托车铸件对挤压压铸工艺生产的需要。 相似文献
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S queeze casting has been widely used for automotive struc tural parts because it offers a vast material selection from aluminum and magnesium alloys. In comparison with low pressure die casting, squeeze casting also overcomes many fluidity problems and thus it can use both hypereutectic and hypoeutectic alloys such as 319, 383 and 390. Squeeze casting can also apply “spot solidification” technology in addition to directional solidification method. The shortcoming of directional solidificati… 相似文献
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挤压铸造比压对铜合金阀体性能的影响 总被引:2,自引:2,他引:0
指出了压力铸造及热挤压工艺生产铜合金阀体的缺点 ,阐述了挤压铸造工艺的特征 ,介绍了挤压铸造在燃气器具铜合金阀体上的应用 ,分析了比压对产品性能的影响 相似文献
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The effect of casting temperature on the properties of squeeze cast aluminium and zinc alloys 总被引:3,自引:0,他引:3
Gravity casting and squeeze casting were carried out on an aluminium alloy with 13.5% silicon and a zinc alloy with 4.6% aluminium with different temperatures, 660, 690 and 720 °C for the former and 440, 460 and 480 °C for the latter. A top-loading crucible furnace was used to melt the alloys. The die-preheat temperatures used were 200–220 °C for the aluminium alloy and 150–165 °C for the zinc alloy. A K-type thermocouples with digital indicator were used to measure the die surface temperature and the molten metal temperature; while a 25 t hydraulic press with a die-set containing a steel mould was used to perform the squeeze casting with a pressure of 62 MPa. Tensile, impact and density tests were carried out on the specimens. It was found that casting temperature had an effect on the mechanical properties of both gravity cast and squeeze cast aluminium and zinc alloys. The best temperatures to gravity cast the aluminium alloy and the zinc alloy were 720 and 460 °C, respectively. For the squeeze casting of the aluminium alloy, the best temperature to use was either 690 or 660 °C; the former would give a better property at the top of the casting while the latter, at the bottom of the casting. However, for the squeeze casting of the zinc alloy, the best temperature was again 460 °C. 相似文献
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Ming Zhou Henry Hu Naiyi Li Jason Lo 《Journal of Materials Engineering and Performance》2005,14(4):539-545
High-pressure die cast magnesium alloy AM50 is currently used extensively in large and complex shaped thin-wall automotive
components. For further expansion of the alloy usage in automobiles, novelmanufacturing processes need to be developed. In
this study, squeeze casting of AM50 alloy with a relatively thick cross section was carried out using a hydraulic press with
an applied pressure of 70 MPa. Microstructure and mechanical properties of the squeeze cast AM50 with a cross-section thickness
of 10 mm were characterized in comparison with the die cast counterpart. The squeeze cast AM50 alloy exhibits virtually no
porosity in the microstructure as evaluated by both optical microscopy and the density measurement technique. The results
of tensile testing indicate the improved tensile properties, specifically ultimate tensile strength and elongation, for the
squeeze cast samples over the conventional high-pressure die cast parts. The analysis of tensile behavior show that the strain-hardening
rate during the plastic deformation of the squeeze cast specimens is constantly higher than that of the die cast specimens.
The scanning electron microscopy fractography evidently reveals the ductile fracture features of the squeeze cast alloy AM50. 相似文献
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The ability to produce near net shape components with good surface finish is made possible by means of squeeze casting, a hybrid metal forming process combining features of both casting and forging in a single operation. The primary objective of this paper is to analyze the influence of the process parameters on surface roughness in squeeze casting of LM6 aluminium alloy using Taguchi method. In Taguchi method, a three level orthogonal array has been used to determine the S/N ratio. Analysis of variance and the ‘F’-test values are used to determine the most significant process parameters affecting the surface roughness. The results indicated that the squeeze pressure and the die preheating temperature are the recognized parameters to cause appreciable improvement in the surface finish of the squeeze cast components. 相似文献
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