A study of the chemical behavior of TiNi shape memory alloy

• Main Authors: Wu,Shyh-Wei, 吳世維
• Other Authors: Wu,Shyi-Kaan
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/82534345302355201003

碩士 === 國立臺灣大學 === 材料科學(工程)研究所 === 84 === The corrosion and oxidation behaviors of TiNi and TiNiCu shape m- emory alloys(SME) have been investigated.In this study,we focus on four kinds of SME:(1)equi-atomic TiNi alloy (2)Ti-40at% Ni-10Cu at%(B) alloy (3)solution treated Ti-51%Ni(C) alloy (4)solution and aging treated(400℃*1hr) Ti-51at%Ni(D) alloy. Imersion and p- otentiodynamic polarization experiments were carried out in sol- utions of 1M nitric acid,1M sulfuric acid,0.9% salt solution and artificial saliva.It reveals that the sequence of the corrosion resistance of four alloys in 1M nitric acid is:(C)>(D)>(A)>(B), but in the other three solutions is:(B)>(C)>(D)>(A).All alloys exhibit excellent corrosion resistance in these solutions.The h- igh temperature oxidation test reveals that the oxidation rates are parabolic and the activation engery is 226,227 and 178KJ/mol for alloy (A).(D) and (B) respectively.The morphology and compo- sition of the scale are analyzed by SEM.EPMA and XRD.The oxidat- ion mechanisms of TiNi and TiNiCu are also proposed in this stu- dy.