應用於大型風力發電機之厚壁球墨鑄鐵件之技術研發

Development of Casting Technologies for Heavy Section Ductile Iron Castings Used in Large-scale Windmills

林其加(Chi-Chia Lin)

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(2013年)

https://doi.org/10.6342/NTU.2013.01866

摘要

本研究針對大型風力發電機之關鍵零組件，探討化學成份對於顯微組織(球化率、球墨數、波來鐵含量)及機械性質(抗拉強度、降伏強度、伸長率、低溫衝擊性能)的影響，以建立符合各種不同材質規格之最佳合金設計及熔鑄條件。此外，本研究以迴歸分析的方法，建立化學成份、顯微組織與機械性質之相關性迴歸方程式。此相關性迴歸方程式可針對不同規格要求的鑄件，提供最佳之合金設計及顯微組織，此外，亦可由化學成份及顯微組織依據特定之迴歸方程式來預測鑄件之各項機械性質。又，由上述實驗所獲得之分析結果為基礎，以不同來源之生鐵、不同處理劑添加比例以及不同之二次接種方式鑄造70mm Y-block之分離試樣，以得到最佳之來源生鐵、處理劑添加比例及二次接種方式，並驗證迴歸方程式之準確性。本研究選取2MW機座(Main frame)鑄件為載具，進行模流及凝固分析，以建立澆流道及冒口系統之最適設計技術。

關鍵字

大型風力發電機 ； 球墨鑄鐵 ； 合金設計 ； 抗拉性質 ； 低溫衝擊性質 ； 迴歸分析 ； 澆流道及冒口設計 ； 模流及凝固分析

並列摘要

The primary purpose of this research is to establish the optimal alloy design and microstructure for achieving the desired mechanical properties (tensile strength, yield strength, elongation and low temperature impact value) of key casting components used in large-scale windmills. Based upon the experimental results from cast-on specimens (series A), multiple regression analyses have been performed to correlate the mechanical properties with chemical compositions and microstructures. The derived regression equations can be used to attain the optimal alloy design for castings with targeted specification. Furthermore, by employing these regression equations, the mechanical properties can be predicted based upon the chemical compositions and microstructures of cast irons. On the other hand, the type of pig irons, the addition amount of nodularizer, ladle and late inoculant, and the method of late inoculation were also investigated in this study. Furthermore, computer simulation was performed on 2 MW main frame casting to simulate the filling and solidification phenomena for achieving the optimal gating and riser system design.

並列關鍵字

Large-scale windmill ； Ductile cast iron ； Alloy design ； Tensile property ； Impact toughness ； Regression analysis ； Gating and riser system design ； Computer simulation

參考文獻

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