應變速率及溫度在鈦合金塑變行為上之效應分析

The Analysis of Effects of Strain Rate and Temperature on Plastic Deformation Behaviour of A Titanium Alloy

李偉賢(Woei-Shyan Lee) ； 林文生(Wen-Sheng Lin)

《鑛冶：中國鑛冶工程學會會刊》 39卷2期 (1995/06) Pp. 125-133

摘要

本文之主旨為使用熱偶合彈塑性理論及有限元素法，分析應變速率及溫度對鈦合金塑變行為之效應與分析。研究之材料選取鈦合金中用量最多、用途也最廣泛的Ti-6AI-4V。應用套裝軟體MARC模擬試片在受恆溫等速鍛粗時，試片內部之溫度、應變速率、應力及等效塑性應變之分佈情形。模擬時試件設定在25℃、200℃、400℃、600℃等四種不同之鍛溫，再分別以0.01S^(-1)、0.1S^(-1)、1S^(-1)、10S^(-1)、100S^(-1)等五種不同之應變速率作40％高度縮減率之塑性變形。由研究中可發現Ti-6 AI-4V為具溫度及高應變速率敏感性之材料。期藉由理論分析瞭解材料受變形參數之影響效應，以減少製造時之錯誤發生。

並列摘要

The purpose of this paper is to study the effects of strain rate and temperature on plastic deformation behaviours of a titanium alloy by using thermal-coupled elastic-plastic theory and finite element method. The material studied is the most extensively used titanium alloy Ti-6Al-4V. In this paper, the isothermal upsetting under a fixed deformation rate is simulated with MARC finite element code to realize the distributions of temperature, strain rate, strain and equivalent plastic strain in specimen. Four different forging temperatures including 25°C、200°C、400°C、600°C and five different strain rates including 0.01S^(-1)、0.1S^(-1)、1S^(-1)、10S^(-1)、100S^(-1) are set under simulating to produce plastic deformation of 40% height reduction. The results show that Ti-6Al-4V is sensitive both to strain rate and to temperature. With aid of theoretical analysis, the effects of deformation parameters on material deformation behaviour are clearly known thus the manufacture mistakes can be avoided.