晶粒尺寸對鈦-10釩-2鐵-3鋁合金機械性質之影響

Effect of Grain Size on the Mechanical Properties of Ti-10V-2Fe-3Al Alloy

李智能(Zhi-Neng Li)

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(2019年)

https://doi.org/10.6346/NPUST201900255

摘要

本文主要探討鈦-10釩-2鐵-3鋁合金，經800℃與700℃不同時間熱處理之顯微結構；同時，設計應用於高爾夫球頭打擊面之製程。研究結果如下。
合金原料具(α+β)雙相組織，經800℃熱處理時，SEM觀察顯示：時間達16分鐘時，完全變態為β相組織；TEM分析則可觀察到： (β+α+ω) (β+α)  β相變態。於700℃熱處理時，SEM觀察顯示：時間達16分鐘時，從優組織結構消失。TEM分析則可觀察到：α相與β相界面存在差排組織；惟延長時間時，則界面差排消失。
合金板材厚度3mm時，抗拉強度、降伏強度與延伸率，分別約為145ksi、132ksi、12%。於800℃熱處理時，其抗拉強度、降伏強度與延伸率，呈現下降趨勢，分別介於135~125ksi、65~75ksi、11~14%；且可觀察到雙降伏特徵；彎曲強度則介於301.4~316.5ksi。而，於700℃熱處理時，抗拉強度、降伏強度與延伸率，則分別介於135~130ksi、120~115ksi、14~16%，無觀察到雙降伏特徵；彎曲強度則介於292.4~304.0ksi。
合金鈦錠，經800℃至700℃連續熱滾軋，且於500℃持溫後，合金抗拉強度、降伏強度與延伸率，分別約為210~215ksi、200~205ksi、6~8%；應用於高爾夫球頭時，於打擊面厚度為2.79~2.94mm厚度時，中心之特徵時間(CT)值，可達285~297μs，性質優於目前商用64鈦材質之高爾夫球頭。

關鍵字

鈦合金 ； 顯微結構 ； 高爾夫球頭 ； 界面差排 ； 機械性質

並列摘要

The main purposes of present manuscript are to analyze the microstructures of the Ti-10V-2Fe-3Al alloy heated at 800℃ or 700℃ for various times. And, the application on Golf-Head Club also performed. Some results are described as following:
The microstructure of the raw alloy is a (α+β) duplex phase. When heated at 800℃, the microstructure would be full β phase with heating time being 16 min.. And, a (β+α+ω) (β+α)  βphase transition would be observed.Meanwhile, during heating at 700℃, the texture morphology and interfacial dislocation would be disappeared while heating time being 16 min..
The UTS, YS and elongation of the raw alloy with 3.0mm thickness are 145ksi, 132ksi and 12%, respectively. Heated at 800℃, The UTS, YS and elongation of the alloy are in the range of 135~125ksi, 65~75ksi amd 11~14%, respectively. Additionally, double yielding would be found. And, the bending strength is in the range of 301.4~316.5ksi. When heated at 700℃, The UTS, YS and elongation of the alloy are in the range of 135~130ksi, 120~115ksi and 14~16%, respectively. Bending strength is between 292.4 and 304.0ksi.
In addition, during continuous hat rolling at temperature between 800℃ and 700℃ and then heated at 500℃, the The UTS, YS and elongation of the present alloy would increase of 210~215ksi, 200~205ksi, and 6~8%, respectively.Compared with 64Ti alloy, the Golf Head producted by present alloy possess higher CT, of which being 285~297μs with the 2.79~2.94mm thickness of hitting face.

並列關鍵字

Titanium alloy ； Microstructure ； Golf Head ； Interfacial dislocation ； Mechanical property

參考文獻

[1] 劉侑誠，2017，鐵-15鉻-4鎳-3銅合金鑄件機械性質分析，碩士論文，國立屏東科技大學，機械工程研究所

[2] The United States Golf Association and R&A Rules Limited 2012, pp.147-158

[3] 許勝安，2014，高爾夫球頭材質探究，碩士論文，國立屏東科技大學，機械工程研究所

[4] Juan Zhao, Jie Zhong, Fei Yan, Fang Chai, Matthew Dargusch, 2017, “Deformation behaviour and mechanisms during hot compression at supertransus temperatures in Ti-10V-2Fe-3Al,”Materials Science and Engineering,710,616-627.

[5] G. Srinivasu, Y. Natraj, A. Bhattacharjee, T.K. Nandy, G.V.S. Nageswara Rao, 2013, “Tensile and fracture toughness of high strength β Titanium alloy, Ti–10V–2Fe–3Al, as a function of rolling and solution treatment temperatures,”Materials Science and Engineering,47,323-330.