消失模型鑄造法之製程技術開發

Development of Lost Foam(LF) Casting Process

王子威(Zih-Wei Wang)

指導教授 ： 潘永寧

國立臺灣大學/工學院/機械工程學研究所/碩士(2006年)

https://doi.org/10.6342/NTU.2006.00540

摘要

中文摘要 本研究針對消失模型鑄造法，選擇以球墨鑄鐵「壓圈」及「套筒」為載具，探討一些關鍵製程參數，如: 塗層材料、塗層厚度、模砂性質、模型材料性質、澆注溫度、流路系統設計等，對於鑄鐵件品質之影響，以建立消失模型鑄造法之量產技術。 根據本研究之實驗結果可獲致以下結論: (1) 消失模型鑄造法所使用之最佳保利龍模型密度應小於0.20 g/cm3 ，(2) 在造模填砂過程中需施以震動，且填滿後再持續震動一段時間，可提升模砂的堆積密度，並有效防止澆鑄時模砂發生崩塌現象，以得到理想的熔液充模， (3) 在鑄件頂部(凸緣)離進模口遠端處設計一溢流部(冒口)時，可顯著提升鑄件之外觀品質及消除內部(凸緣位置)縮孔， (4) 由消失模鑄件之尺寸量測結果得知，其固態收縮率約為1％。

關鍵字

消失模型鑄造法 ； 砂心 ； 壓圈 ； 套筒 ； 保麗龍模型

並列摘要

Abstract In this study, in order to establish the manufacturing technology of the lost foam casting process, the “seal ring” and “sleeve barrel” ductile iron castings were chosen as the carriers, and the effects of some selected processing parameters, such as pattern density, pattern coating, and gating system design, on the quality of the castings produced were studied. Based upon the results obtained, the following conclusions can be drawn: (1) The density of the foam pattern employed should remain in a suitable range, no higher than 0.02 g/cm3. (2) Vibration should be applied during the sand-filling process, and continue for a certain period of time after complete fill, in order to achieve better compaction and also reduce the propensity of mold collapse during casting. (3) For the “sleeve barrel” casting, designing an suitable over-flow (or a riser) at the upper, far side of the flange of the casting can serve as a reservoir for the thermal decomposed products of the foam pattern, which can effectively eliminate both the surface defects and internal shrinkage porosities, and hence, quality castings can be attained. (4) The percent solid contraction measured in the lost foam ductile iron castings is around 1%.

並列關鍵字

Lost foam ； seal ring ； sleeve barrel ； ductile iron ； Thermal decomposed products

參考文獻

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參考文獻