高温环境下Ni47Ti44Nb9形状记忆合金拉伸行为研究  

Study on Tensile Behavior of Ni_(47)Ti_(44)Nb_9 Shape Memory Alloys Under High Temperature

作　　者：刘洪涛[1] 孙光爱[2] 

机构地区：[1]东北大学 材料各向异性与织构教育部重点实验室,辽宁沈阳110819 [2]中国工程物理研究院中子物理学重点实验室核物理与化学研究所,621900

出　　处：《热加工工艺》2013年第8期39-41,共3页Hot Working Technology

基　　金：国家自然科学基金资助项目(11105128)

摘　　要：在25～450℃内,沿轧向及横向研究了Ni47Ti44Nb9形状记忆合金的高温拉伸力学性能。结果表明:在室温下,沿轧向拉伸时出现了明显的应力平台,而沿横向拉伸则无此现象,这是由于不同的解孪晶机制造成的。当温度升高至100、300℃时,屈服强度增加,而断裂时的最大应变减小,在此温度下Ni47Ti44Nb9合金变得更加硬而脆。随温度进一步升高到450℃,Ni47Ti44Nb9合金的抗拉强度迅速减小,断裂时的最大应变再次增加,这表明此时合金变软,粘性增强。Ni47Ti44Nb9 shape memory alloy was studied by high temperature tensile experiments at 25-450 ℃ along the rolling and the transverse directions, respectively. The experimental results show that： the stress-plateau in the stress-strain curve appears along the rolling direction at 25 ℃. While, along the transverse direction, the stress-plateau disappears at 25 ℃. It is due to the different detwinning mechanism. With the increasing temperature to 100 ℃ and 300 ℃, the yield strength increases and maximum strain decreases, which indicate that the alloys become hard and brittle at those temperatures. With the temperature increasing to 450 ℃, the tensile strength drops rapidly and the maximum strain raises again, which can reveal that the alloys become soft and viscous.

关 键 词：形状记忆合金 NI47TI44NB9 高温拉伸 

分 类 号：TG139[一般工业技术—材料科学与工程]