Modification of the Recovery Behavior of TiNi Shape Memory Alloy (SMA) by Chemical Heat Treatment
来源期刊:材料热处理学报2004年第5期
论文作者:MIN Si-lin WANG Gao-chao YANG Gang HUANG Yi-bin
关键词:TiNi shape memory alloy; Samariuming; Linear reversion;
摘 要:In order to improve the linear recovery behavior, TiNi shape memory alloy springs were samariumed at 550℃for 4 hours with SmH3 as samarium source, in a vacuum furnace. The phase of samariumed layer was determined by X-ray diffractometer (XRD). The fracture surface of TiNi SMA spring was investigated by scanning electronic microscope (SEM). The experimental results indicate that a 2μm thick samariumed layer composed of NiSm intermetallics existed on the fracture surface. Additionally, a new idea of linear recovery behavior in shape memory alloy(SMA) has been proposed, and its properties have been defined. The reversion measurements show that the linear recovery properties of TiNi SMA were obviously improved. The temperature range of the linear reversion (Tw) was enlarged from 4℃ to 8℃, The ratio of linear reversion (η) was increased from 54% to 75%, the proportion of linear reversion (PL) was increased from 56% to 70%, and the proportion of non-linear reversion (Ps) was decreased from 44%to 10%, but the proportion of total reversion (PT) has a little decrease. These results were attributed to the strengthening effect of NiSm intermetallics.
MIN Si-lin1,WANG Gao-chao1,YANG Gang1,HUANG Yi-bin1
(1.College of Materials Science and Engineering, Nanchang Institute of Aeronautical Technology, Nanchang, China)
摘要:In order to improve the linear recovery behavior, TiNi shape memory alloy springs were samariumed at 550℃for 4 hours with SmH3 as samarium source, in a vacuum furnace. The phase of samariumed layer was determined by X-ray diffractometer (XRD). The fracture surface of TiNi SMA spring was investigated by scanning electronic microscope (SEM). The experimental results indicate that a 2μm thick samariumed layer composed of NiSm intermetallics existed on the fracture surface. Additionally, a new idea of linear recovery behavior in shape memory alloy(SMA) has been proposed, and its properties have been defined. The reversion measurements show that the linear recovery properties of TiNi SMA were obviously improved. The temperature range of the linear reversion (Tw) was enlarged from 4℃ to 8℃, The ratio of linear reversion (η) was increased from 54% to 75%, the proportion of linear reversion (PL) was increased from 56% to 70%, and the proportion of non-linear reversion (Ps) was decreased from 44%to 10%, but the proportion of total reversion (PT) has a little decrease. These results were attributed to the strengthening effect of NiSm intermetallics.
关键词:TiNi shape memory alloy; Samariuming; Linear reversion;
【全文内容正在添加中】