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随着科学技术和市场竞争的发展,对内燃机性能的要求急剧提高,对其心脏另件活塞的耐磨性、耐蚀性、尺寸稳定性以及高温强度等性能的强化程度的要求也不断提高,当前能够满足这些力学性能、铸造性能和使用寿命性能的材料,主要是亚共晶、共晶、伪过共晶和过共晶铝硅系合金,而能够满足上述强化要求的手段之一,86年国际上有关权威认为仍然是液锻技术。试验研究的牌号有ZL110、ZL108、ZL109、SAE321、K S283以及Si量高达22～26％的高硅过共晶合金;试验中还对Ca、Mg、Mn等含量变化的影响进行了研究。 液锻技术的工艺参数,主要有比压、加压速度、保压时间、模具条件、合金熔炼质量和浇铸质量等。在设备一经选定,工艺参数一经确定,则合金的溶炼质量与浇铸质量就成为关键的决定因素。正如前述,液锻模具不设置浇冒口系统,因此其铸造条件远比传统铸造来得苛刻,常会出现其它铸造可以避免的缺陷,如细微夹杂或夹渣。从活塞大批生产的情况来
With the development of science and technology and market competition, the performance requirements of the internal combustion engine have been drastically increased, and the demand for strengthening the wear resistance, corrosion resistance, dimensional stability and high temperature strength of the piston of the heart part has also been continuously raised. Materials currently capable of meeting these mechanical properties, casting properties and service life properties are mainly hypoeutectic, eutectic, pseudo-hypereutectic and hypereutectic Al-Si based alloys, and one of the means to meet the above stringent requirements, 86 International authority that is still the international forging technology. The experimental study grades ZL110, ZL108, ZL109, SAE321, K S283 and Si content as high as 22-26% of high silicon hypereutectic alloys; test also Ca, Mg, Mn and other content changes were studied. Liquid forging technology process parameters, the main pressure, pressure speed, dwell time, mold conditions, alloy melting quality and casting quality. Once the equipment is selected and the process parameters are established, the quality of the alloy and the quality of the casting become critical determinants. As mentioned above, the liquid forging die set does not set Riser system, so the casting conditions far more harsh than the traditional casting, often casting other defects can be avoided, such as subtle inclusions or slag. From the piston mass production situation