陳永傳臺灣大學:機械工程學研究所李健維Lee, Chien-WeiChien-WeiLee2010-06-302018-06-282010-06-302018-06-282009U0001-2201200923095200http://ntur.lib.ntu.edu.tw//handle/246246/187129本研究將SKD61、SKH51、SKD11、SUS420J2等各種工具鋼施以滲氮處理、氧化處理及滲氮氧化複合處理後，置於720℃的鋁合金熔液中實施熔蝕試驗，由試片單位面積的重量減少量評估上述各種表面改質處理對鋼料耐鋁液熔蝕效果的影響。並配合顯微組織的觀察、化學成分的分析及X-ray繞射實驗，探討鋼料在鋁液中的熔蝕反應機構。實驗結果顯示，鋼料經滲氮或氧化處理後對於抵抗鋁液的熔蝕能力都有顯著增加，尤其是滲氮氧化複合處理的效果最好，鋼料經滲氮氧化複合處理後，在相同條件下的熔蝕量不到原材的十分之一。鋼料在鋁液中的蝕反應主要是由於鋼料中的鐵元素(Fe)擴散到鋁液中，和鋁液中的鋁(Al)、矽(Si)等元素形成Fe-Al-Si金屬間化合物。由於滲氮層及氧化層有阻礙鐵元素(Fe)擴散到鋁液中的效果，故能降低鋼料在鋁液中的熔蝕速率。Tool steels, such as SKD61, SKH51, SKD11 and SUS420J2, after nitriding, oxidation, or nitride-oxidation compound treatment are dipped in liquid aluminum at 720℃ for erosion tests. Effects of above surface modification treatments on the resistance of steels to erosion in liquid aluminum are evaluated by weight loss per unit surface area. Furthermore, erosion mechanism of steels in liquid aluminum is investigated through microstructure observation, chemical composition analysis and X-ray diffraction test. The experimental results show that the resistance of steels to erosion in liquid aluminum can be significantly increased either by nitriding or oxidation treatment. Moreover, the effect of resisting erosion for nitride-oxidation compound treatment in especially excellent. The weight loss of steel sample after the compound treatment is smaller than one tenth of the plain steel at the same erosion test conditions. The dominant process of erosion mechanism in that the iron atom of steels diffuses to liquid aluminum and formed Fe-Al-Si intermetallic compounds with the element of aluminum and silicon in the liquid. Either the nitrided layer or oxidation layer of steels is a barrier for iron atom to diffuse to liquid aluminum that results in the reduction of erosion rate of steels.第一章 緒論...............................................1.1 前言..................................................1.2 研究動機與目的........................................2二章 實驗理論...........................................3.1 氧化處理..............................................3.1.1 氧化處理............................................3.1.2 氧化處理之氧化層....................................4.1.3 時間對氧化速度之影響................................5.1.4 氧化膜對耐熔蝕性的影響..............................5.2氣體滲氮處理...........................................5.3固體粉末滲氮處理.......................................7.4熔蝕現象...............................................7.4.1 Kirkendall效應......................................7.4.2孔洞之產生...........................................7.4.3裂痕之產生...........................................8.4.4熔蝕現象.............................................8.4.5滲氮處理模具鋼之熔蝕現象.............................9.4.6化合物層的生成和組織.................................9.4.7鋁合金Si元素對化合物層之影響.........................9三章 實驗設備與方法....................................10.1 實驗規劃.............................................10.2 實驗設備.............................................10.2.1熔蝕處理之設備......................................10.2.2固體滲氮之處理......................................10.2.3氣體滲氮之處理......................................11.2.4空氣氧化之處理......................................11.2.5水蒸氣氧化之處理....................................11.2.6實驗儀器............................................12.3 實驗方法.............................................12.3.1試片種類及前處理....................................12.3.2粉末滲氮處理........................................13.3.3氣體滲氮處理........................................13.3.4氧化處理............................................13.3.4.1空氣中氧化處理....................................13.3.4.2水蒸氣中氧化處理..................................13.4鋼料經滲氮處理後之試驗與分析..........................14.4.1電子微探儀(EPMA)試驗................................14.4.2顯微組織觀察........................................14.4.3 X光繞射分析(XRD,X-ray diffraction).................15.4.4硬度試驗............................................15.4.5融熔試驗時的重量減少量..............................16四章 結果與討論........................................18.1熔蝕機制..............................................18.1.1 熔蝕後的顯微組織...................................18.1.2熔蝕過程............................................19.2 工具鋼施以表面處理後對熔蝕量之影響...................21.2.1各種工具鋼在鋁液中的熔蝕性比較......................21.2.2各種工具鋼經固體滲氮後在鋁液中的熔蝕性比較..........21.2.3各種工具鋼經固體滲氮氧化複合處理後在鋁液中的熔蝕性比較 .....................................................22.2.4氮化處理對鋼料耐鋁液熔性的影響......................22.2.5氧化處理對鋼料耐鋁液熔蝕性的影響....................23.2.6氮化氧化複合處理對鋼料耐鋁液熔蝕性的影響............23.2.7熔蝕機構之探討......................................24五章 結論..............................................27 考 文 獻..............................................694632510 bytesapplication/pdfen-US工具鋼滲氮氧化熔蝕Fe-Al-Si金屬間化合物Tool steelNitridingOxidationErosionFe-Al-Si inermetallic compoundthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/187129/1/ntu-98-R95522720-1.pdf