Study on Fatigue Properties of Shape Memory Alloys

形状记忆合金疲劳性能研究

• 批准号: 03650568
• 负责人: MIYAZAKI Shuichi
• 金额: $ 1.41万
• 依托单位: Institute of Materials Science, University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1992
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03650568/
• 关键词: Ti-Ni; Ni-Ti; Shape memory alloy; Shape memory effect; Superelasticity; Fatigue; Fatigue crack; Fatigue life; き裂伝播速度; 形状記憶金; 疲労き裂; TiーNi; NiーTi

Fatigue tests have been made in order to investigate the fatigue life, fatigue crack nucleation and fatigue crack propagation in Ti-Ni shape memory alloys. The following results were obtained.(1) The data of fatigue lives can be expressed by two lines, the slope of the line in the shorter life region being steeper than that in the longer life region. The former line expresses the fatigue life under cyclic superelastic deformation, while the latter line that under cyclic elastic deformation.(2) The fatigue life was almost the same irrespective of melting method.(3) Fatigue crack uncleated at TiC inclusions in specimens which were made by high frequency induction melting, while they nucleated along grain boundaries in specimens which were made by electron beam melting.(4) Fatigue crack propagation rate increases with increasing test temperature in a temperature range between Ms and Td; above Td the stress-induced transformation does not occur or the critical stress for inducing martensites is too high to relax the stress concentration at a crack tip effectively.

为了研究Ti-Ni形状记忆合金的疲劳寿命、疲劳裂纹形核和疲劳裂纹扩展，进行了疲劳试验。得到了以下结果：(1)疲劳寿命数据可以用两条线表示，短寿命区域的线斜率比长寿命区域的线陡。前者表示循环超弹性变形下的疲劳寿命，后者表示循环弹性变形下的疲劳寿命。(2)无论熔化方式如何，其疲劳寿命几乎相同。(3)高频感应熔炼试样中TiC夹杂物沿晶界形核，而电子束熔炼试样中TiC夹杂物沿晶界形核。(4)在Ms ~ Td温度范围内，疲劳裂纹扩展速率随试验温度的升高而增大；在Td以上，应力诱导转变不发生，或者诱发马氏体的临界应力过高，不能有效地缓解裂纹尖端的应力集中。

项目成果

田中 喜久昭,戸伏 壽昭,宮崎 修一: "形状記憶合金の機械的性質" 養賢堂, (1993)

Kikuaki Tanaka、Toshiaki Tobushi、Shuichi Miyazaki：“形状记忆合金的机械性能” Yokendo，（1993）

田中 喜久昭: "形状記憶合金の機械的性質" 養賢堂, (1992)

Kikuaki Tanaka：“形状记忆合金的机械性能” Yokendo，（1992）

宮崎 修一: "機能性材料の疲労-形状記憶合金" 材料.

宫崎修一：“疲劳功能材料——形状记忆合金”材料。

田中 喜久昭,戸状 壽昭,宮崎 修一: "形状記憶合金の機械的性質" 養賢堂, (1993)

Kikuaki Tanaka、Toshiaki Togai、Shuichi Miyazaki：“形状记忆合金的机械性能” Yokendo，（1993）

S.Miyazaki: "Fatigue of Shape Memory Alloys"

S.Miyazaki：“形状记忆合金的疲劳”