Sn含量对Ti-Nb-Sn合金组织及相结构的影响

Effect of Sn content on microstructure and phase structure of TiNbSn alloy

制备不同成分的TiNbSn合金,分别进行了DTA、XRD和TEM分析。结果表明,随着Sn含量的增加,TiNbSn合金晶粒尺寸减小;当Sn含量≤4.2mol%时,合金未发生马氏体相变。当Sn含量为4.71mol%和5.02mol%时,合金在加热过程中热弹性马氏体消失,在冷却时形成。这两种合金具有对室温相以及高温相的形状记忆效应。

TiNbSn alloys with different composition were prepared. The microstructure and phase transformation behavior of the alloys were investigated by thermal analysis, X-ray diffraction and transmission electron microscopy. The results show that grain size of the TiNbSn alloys decreases with increasing Sn content. While Sn content is less than and equal to 4.2mol%, no martensite transformation occurs. When Sn content achieves 4.71mol% or 5.02mol%, thermal-elastic martensite of the alloy disappears as it is heated, and re-forms in the following cooling process. The two alloys with Sn contents of 4.71mol% and 5.02mol% exhibit a two-way shape memory effect.