彎曲塑性變形對鈦-20釩-4鋁-1錫合金顯微結構之影響

近30年，鈦合金在民生工業被廣泛的應用，如：眼鏡架、腳踏車車架、網球拍、高爾夫球頭等。其相關的研究與應用主要為，1.各類合金元素於鈦合金之合金設計，2.強度、延伸率、疲勞強度、磨耗…等機械性質探討，3.成分、溫度、時間與相變化關係，4.鑄造、滾軋、鍛造、3D列印…等加工製程方法與參數調整。本文利用SEM、XRD、TEM分析方法，研究鈦-20釩-4鋁-1錫合金，經彎曲壓縮後，顯微結構的變化。結果如下： 1. SEM觀察顯示：鈦-20釩-4鋁-1錫合金3.30±0.05mm板材，在彎曲壓縮過程中，初始表層會形成加工麻田散體(平行組織)結構；隨著彎曲量增加，麻田散體結構往內部擴展，同時，於結構內部亦可觀察到微細針狀組織。 2. XRD與TEM分析顯示：在彎曲壓縮過程中，初始於β相基地會形成大量的差排，亦可觀察到多晶化特徵；隨著彎曲量增加，於基地內可觀察到微細的α相顆粒存在，且逐漸成長為完整區域。此外，於微細針狀組織結構內，可觀察到島狀ω相顆粒。

關鍵字

鈦合金；彎曲；顯微結構；加工麻田散體；針狀組織

並列摘要

Recently, Titanium and Titanium alloys have been widely investigated and applied on the minsheng industry, incuding glaeeses, bicycle, temis and golf clubs etc. And, their researches are focused on alloy design, mechanical property, phase transformation and manufatural processes. The purposes of present studies are to investigate on the microstructures of the Ti-20V-4Al-1Sn alloy during the bending processes. The main results are described as following: 1. Based on the SEM observation, some stress induced martensite with parallel morpholgy formed on surface layer or within center part during bending processes. Meanwhile, some plate-like structure also formed within parallel-morpholgy martensite of which the higher-bending worked. 2. Based on The XRD and TEM examination, during the bending proceses, high-density of dislocations and poligonization characterics observed in initial stage. Additionally, with increasing bending work, some α-phase particles are observed within β-phase matrix, and then grown to whole matrix. Meanwhile, some ω-phase particles are observed on the interface of β-phase matrix.