- 學位論文
Fe-Mn-Si-Cr-Re形狀記憶合金性能最佳化之研究
A Study on Property Optimization of Fe-Mn-Si-Cr-Re Shape Memory Alloys
摘要
Fe-Mn-Si-Cr基形狀記憶合金具有加工性良好、價格低廉等特性，在套筒元件的接合與應用具有其優勢。本實驗於具有良好形狀記憶能力之Fe-Mn-Si-Cr基合金中，嘗試添加微量錸(Re)元素，經過不同熱處理後，進行形狀記憶效應與微結構之檢測分析，並針對形狀記憶效應最高的成分，作熱機訓練與形狀記憶訓練，以達到形狀記憶最佳化之研究。 實驗結果顯示：在Fe-30Mn-6Si-5Cr合金、Fe-30Mn-6Si-5Cr-0.05Re合金、Fe-30Mn-6Si-5Cr-0.1Re合金、Fe-30Mn-6Si-5Cr-0.3Re合金中，經600℃以上的退火處理兩小時，會在晶界與母相中產生BCC結構的析出相，此析出相為成分與母相類似之 相。以添加0.1wt.%的Re，經700℃兩小時的退火處理後，其硬度測試及形狀回復率皆表現最好。 藉Fe-30Mn-6Si-5Cr-0.1Re合金並利用冷輥壓做冷加工處理，預應變量分別為0%、5%、10%、15%、20%。其中以5%應變量之合金在700℃兩小時的退火處理後，形狀回復率最好。以此合金進行形狀記憶訓練，形狀回復率隨著循環次數而遞增，經2次形狀記憶訓練後即接近100%之形狀回復，可得知合併熱機處理與形狀記憶訓練，可以有效達到形狀記憶最佳化之效果。
並列摘要
Fe-Mn-Si-Cr-based shape memory alloys have good workability, low price and advantages in the bonding of the sleeve element. With good shape memory Fe-Mn-Si-Cr-based alloys in this study, we try to add it with trace rhenium (Re) element. After different aging treatment, we go through the bending test and analysis of micro-structure, then we choose the one of the better shape memory effect to do heat treatment and shape memory training. In Fe-30Mn-6Si-5Cr、Fe-30Mn-6Si-5Cr-0.05Re、Fe-30Mn-6Si-5Cr-0.1Re and Fe-30Mn-6Si-5Cr-0.3Re alloys, there will be BCC structure of the precipitated phase in the grain boundaries and the parent phase through aging above 600℃ for 2 hours. It is called phase which is similar to the parent phase. Afer aging at 700℃ for 2 hours, the alloys have the better hardness and shape memory recovery. Apply cold-working on Fe-30Mn-6Si-5Cr-0.1Re alloy to make pre-strain 5%, 10%, 15% and 20%. The shape memory recovery will be better through the one of pre-strain 5% through aging at 700℃ for 2 hours. Use this one to do shape memory training experiment. The recovery rate will increase with training times. After 2 times, the recovery rate will almost be 100%. It is concluded that we can get the best shape memory alloy efficiently by using both heat treatment and shape memory training.