共查询到19条相似文献,搜索用时 180 毫秒
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结合铸件质量要求,基于铸造数值模拟技术,分析了低压铸造的充型凝固过程,预测了铸件中的缺陷分布;最终通过试制,确保了压气室低压铸件质量,为该件的顺利生产奠定了基础. 相似文献
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<正> 低压铸造是利用气体压力将金属液压人铸型,并使铸件在一定压力下结晶凝固的一种特种铸造方法。利用这种方法不仅可以获得比一般重力铸造质量更高的铸件,而且可以铸出一般重力铸造难以成形的大型薄壁复杂铸件。同时低压铸造所用浇注系统十分简单,可使金属的利用率大大提高,通常可在90%以上。 低压铸造技术因设备投资少,上马快,并可得质量较高的铸件,故已渐广泛地应用在铸造生产上。GNLD型法式灯罩外壳低压铸造模具的试模成功,是一个实例。 相似文献
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为了解决水冷机壳铝合金薄壁低压铸件组织内部由于壁厚不均匀以及内部桶状冷却水道砂芯的结构特点所造成的缩孔和缩松等缺陷,采用扫描电镜技术对铝合金铸件样品进行高精度拍照检测分析,为技术人员优化低压铸造结晶凝固冷却技术方案和调整工艺参数提供依据,从而达到低压铸造精细质量控制,提高水冷机壳低压铸造质量. 相似文献
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低压铸造工艺与重力铸造及高压铸造相比具有提高金属液的利用率、提高铸件内部质量、铸造品质一致性好、铸件可以进行热处理、提高生产率、实现自动化操作、降低劳动强度等优点。因此低压铸造工艺在大批量生产的汽车工业中应用不断增加。尤其在优质安全结构件(轮毂、行驶部件等)、发动机结构件(缸体、缸头等)以及结构复杂、高强度、高铸造难度的薄壁铸件(压缩机外壳),低压铸造法特别受欢迎。 相似文献
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大型铝合金铸件低压铸造 总被引:12,自引:3,他引:9
简要阐述了国内外采用低压铸造工艺生产大型铝合金铸件的现状,着重介绍了沈阳铸造研究所近年来在开发大型复杂铝合金铸件砂型低压铸造工艺技术方面所做的工作,列举了典型铝合金铸件的低压铸造工艺参数。 相似文献
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薄壁铝合金铸件一直是铸造界的难题,低压铸造是最佳工艺方法。介绍了低压铸造充型的原理及其工艺特点。重点介绍了铝合金薄壁铸件低压铸造充型工艺及其优化。 相似文献
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采用自制的计算机数据采集系统,测试了低压铸造薄壁件从开始充型到凝固结束全过程的温度变化,分析了薄板件的温度变化规律及分布特点。研究表明,薄壁件的充型形态对温度分面影响很大。测试结果反映了铸件的充填顺序及充型过程中的凝固现象。温度场测试结果可用于验证充型过程流场温度耦合程度的正确性。 相似文献
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Cooling curves were obtained to estimate solidification parameters of a squeeze cast Al–4%Cu alloy under different processing conditions, while microstructural analysis was carried out to investigate grain morphology obtained for the different test runs. The results indicated not only an increase in cooling curve gradient with increase in pressure, but also a change in cooling curve profile with changes in superheat and die temperature. Solidification range was also affected with an increase in liquidus when superheat was high while solidification rate was decreased when superheat was low and die temperature was increased. Microstructure showed refinement, dendritic growth formation and a suppression of both precipitated phase as well as micro-segregation with an increase in cooling rate due to application of pressure. The investigation is expected to provide important insight into the solidification behavior under pressure of an Al–4%Cu alloy that can be used to evaluate its casting feasibility as well as give basic input information for simulation purposes. 相似文献
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Shrinkage defects can be formed easily at critical location during low pressure die casting (LPDC) of aluminum alloy cylinder body. It has harmful effect on the products. Mold filling and solidification process of a cylinder body was simulated by using of Z-CAST software. The casting method was improved based on the simulation results. In order to create effective feeding passage, the structure of casting was modified by changing the location of strengthening ribs at the bottom, without causing any adverse effect on the part's performance. Inserting copper billet at suitable location of the die is a valid way to create suitable solidification sequence that is beneficial to the feeding. Using these methods, the shrinkage defect was completely eliminated at the critical location. 相似文献
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镁合金轮毂低压铸造数值模拟及缺陷预测 总被引:1,自引:1,他引:0
以某镁合金汽车轮毂为研究时象,运用专业铸造模拟分析软件,进行低压铸造数值模拟,研究了填充和凝固过程中温度场的分布,预测了在此过程可能出现的缺陷.模拟结果显示.轮毂中心部位也可能产生缩松,并发现通过降低或者提高充型速度并不能有效解决问题,通过在模具上模增加局部冷却水道,能够较好地改善整体冷却顺序,有效减小轮毂中心的缩松现象. 相似文献
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V. D. Tsoukalas 《International Journal of Cast Metals Research》2013,26(6):581-588
The primary objective of this research is to investigate the effect of machine related parameters on porosity formation in the aluminum die casting process. The amount and distribution of porosity in die castings was examined in relation to plunger velocity during the 1st phase, fast shot set point, plunger velocity during the 2nd phase, die cavity filling time and multiplied pressure during the 3rd phase.Standard statistical analysis was performed in order to identify the effect of each of the considered parameters and parameter interactions on porosity formation. It was found that, among the parameters considered, multiplied pressure, plunger velocity in the 2nd phase and die cavity filling time have the most significant effect on porosity formation. Using optimal die casting machine parameter levels, the optimum porosity value of aluminum alloy die-castings was predicted. The results were confirmed by further experiments. 相似文献