Study On Micro-scale Filling Capacity Of Semi-solid ZL101Alloy

With the development of miniaturization in manufacturing industry, thedemand of micro-parts is growing. Micro-forming technology is a new metalprocessing technology, with high material utilization rate and stableperformance of forming pieces, and it’s suitable for mass production. Thecurrent micro-forming is just in the laboratory, and there is a certain gap fromwide application. However, it is anticipated that micro-forming technologywould have broad prospects in the future. This research has been supported bythe Key Project of Natural Science Foundation of China on micro-formingtechnology.The author selected semi-solid ZL101aluminum alloy which has beenwidely used in industry as the experiment material. According to test resultsof filling specific micro-grooves, the paper analyzes the flow ability ofsemi-solid materials at micro scale, and studies the law that different processparameters work on the micro-scale filling capacity. The author designed andmanufactured the tapered slot dies. A fire-resistant ceramic was used to heatdies, while the AT908-based artificial intelligence temperature controller wasused to get accurate temperature. The results showed that:(1) Groove Width,solid-fraction (formation temperature) and force are all very important tomicro-scale filling capacity of ZL101alloy in semi-solid.(2) The sensitivityof micro-forming properties on diameters decreased with the solid-fractiondecreasing (temperature rises) in the semi-solid temperature range.(3)Smaller the groove width is, more evident advantage of semi-solid formingcompared to solid-state forming is. This paper analyzed the microstructure of the semi-solid micro-formedparts and the remaining billet, and also studied the influence of some factorson microstructures of micro-formed parts. The results showed that:(1) Theprimary structure changed through three stages, eutectic phase melting,α-phase particles nodularization and solid particles growing in filling process.(2) The forefront of formed micro-features retained the microstructure afterre-melting, and it’s different from the microstructure in other positions.(3)The micro-hardness values of different positions in the micro-formed partsare close.