鐵-9鋁-28錳-1.3碳-5鉻合金相變化

The Phase Transformation of the Fe-9Al-28Mn-1.3C-5Cr Alloy

葉嘉雯(Chia-Wen Yeh)

指導教授 ： 趙志燁

國立屏東科技大學/工學院/機械工程系所/碩士(2008年)

https://doi.org/10.6346/NPUST.2008.00088

摘要

2000年起，鐵鋁錳碳合金被應用在高爾夫球頭商品；整體而言，此類商品具有優異的高爾夫擊球特性，廣受好評。本文主要探討鐵-9鋁-28錳-5鉻-1.3碳合金顯微結構與機械性質，期能使鐵鋁錳合金在高爾夫球頭商品有更廣泛的應用性。主要結果如下所示：
合金在1080 ℃固溶處理後，其顯微結構為沃斯田鐵(γ)+微細κ'相碳化物(γ→γ+κ)組織。於450~750 ℃短時間時效處理，可觀察到κ相碳化物在沃斯田鐵基地內整合析出。隨著時效時間(1~96 小時)的增加，晶粒可觀察到不同析出的變態。於550~650 ℃，晶界可觀察到：γ→DO3 + Cr7C3 +β- Mn的反應；溫度提高至750 ℃時，則為γ→DO3 + Cr7C3的反應。
合金經固溶處理後，其機械性質：抗拉強度、降伏強度、延伸率與硬度值，分別約介於780~850 MPa、620~670 MPa、55~90 %與HRc 16-28。隨著κ相碳化物於基地內整合析出，其抗拉強度可增加到1150 MPa，延伸率仍可保持40~45 %。而隨著晶界析出發生，其延伸率則急遽下降。合金於550 ℃/16 小時，600 ℃/4 小時，650 ℃/2 小時，或700 ℃/1 小時時效處理後，合金呈完全脆性。

關鍵字

鐵鋁錳合金 ； 顯微結構 ； 機械性質 ； 高爾夫球頭

並列摘要

Reently, the application of the Fe-Al-Mn-C alloys were focused on the product of the Golf Head. Essentially, these Golf-Heads could posses some excellent properties. However, the manufacture processes would be occurred some problems. The purposes of the studies wre to investigate the phase transformation and mechanic properties of the Fe-9Al-28Mn-1.3C-5Cr alloy. Based on the present study, some main results are described as followings:
When the alloy being SHT at 1080℃, the microstructure was a austenite phase within som extremely fine κ-phase carbides. During aged at 450-750 ℃ for a short time, some fine κ-phase carbides precipitated within the austenitic matrix. Prolonged the aged time, some phase transition sequences were found on the grain boundaries. When aged at temperature of the 550 ℃-650 ℃ for various times, the phase transition sequences was found to be γ→DO3 + Cr7C3 +β- Mn. Increasing the aged temperature to 750 ℃, the phase transition sequences was found to be γ→DO3 + Cr7C3 . In addition, the precipitqates of the Cr7C3 could be found in the specimen being at 1050 ℃.
The alloy being SHT at 1080℃, the Ultimate tensile strength, Yield strength, elongation and hardness were in the range of the 780~850 MPa、620~670 MPa、55~90 % and HRc 16-28, respectively. According to the coherent precipitate of the κ-phase carbides, the Ultimate tensile strength of the alloy would increase to 1150 MPa with the elongation in the range of 40~45 %. In addition, the elongation would decrease dramaticall. When the alloy aged at the 550 ℃/16 H, 600 ℃/4 H, 650 ℃/2 H, or 700 ℃/1 H, the alloy would be entirely embrittlement.

並列關鍵字

Fe-Al-Mn alloy ； microstructure ； mechanical property ； golf-head

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