合金元素Cr及V對於片狀石墨鑄鐵機械性質與金相顯微組織的影響

Effect of Alloying Element Vanadium and Chromium on Mechanical Properties and Microstructure of the Flake Graphite Cast Iron

楊榮顯(Rong-Shean Yang) ； 王亞彰(Ya-Chang Wang)

《鑄造工程學刊》 38卷1期 (2012/03) Pp. 10-20

https://doi.org/10.29809/JTFS.201203.0002

摘要

隨著環境汙染日益的嚴重，環境保護的重要性已是刻不容緩。鑄鐵中經常添加之合金元素鉻（Cr），已被美國EPA列為B級致癌物，因此尋找可替代之合金元素，應是在環境保護之貢獻上可努力的方向之一。本研究是以與鉻（Cr）具有相近功能之合金元素釩（V）為標的，來探討分別添加釩（V) （0.02~0.5wt％）與鉻（Cr) （0.2~1.0wt％）對於片狀石墨鑄鐵之機械性質與金相顯微組織（基地組織、石墨之型態與大小等）的影響，並評估其影響之同質性與差異性。實驗結果顯示隨著合金元素鉻（Cr）添加量之增加其抗拉強度會有逐漸增強的趨勢，但是當添加量大於0.5 wt％以後，抗拉強度則會有明顯減少的趨勢；觀察金相顯微組織發現，隨著合金元素鉻（Cr）添加量的增加，石墨數量會有明顯減少的趨勢，當鉻（Cr）添加量大於0.5wt％時，在基地組織裡會有白鑄鐵組織出現，並隨著鉻（Cr）添加量之再次增加而明顯增加。合金元素釩（V）添之效果，隨著添加量的增加，石墨數量有明顯減少及微細化之趨勢。

關鍵字

鉻 ； 釩 ； 片狀石墨鑄鐵 ； 機械性質 ； 金相顯微組織

並列摘要

Due to the increasing of environmental pollution, it is imperative to highly respect the importance of environmental protection. The alloying element chromium (Cr), which is often added to cast iron, is regarded as Class B carcinogen by U.S. EPA. Thus, it deserves attention to make more efforts on looking for substitutive alloying elements so as to make contribution on environmental protection.The objective of this research is to adopt the alloying element vanadium (V), which has the similar properties with chromium (Cr), as the substitutive target. The effects of alloying element vanadium (V) (0.02~0.5wt％) and chromium (Cr) (0.2~1.0wt％) on the mechanical properties and metallographic microstructures (matrix structure, morphology, size of graphite, etc.) of the flake graphite cast iron are investigated. The homogeneity and differences of these two alloying elements are also evaluated in this research.Experimental result shows that with the increasing of the alloying element chromium (Cr), the tensile strength will increase gradually at beginning. However, as the addition amount of the alloying elements chromium (Cr) is over 0.5 wt%, the tensile strength will decrease remarkably. Metallographic microstructures show that with the increasing of the alloying elements chromium (Cr), the amount of graphite will significantly reduce. As chromium (Cr) is over 0.5 wt%, the white cast iron structure will appear on the matrix, and which increases with the increasing of the chromium (Cr). The amount of graphite will be reduced and minute significantly by increasing the alloying element vanadium (V).

並列關鍵字

chromium ； vanadium ； flake graphite cast iron ； mechanical property ； metallographic microstructure