Damping Characteristics of Ti50Ni50−xCux (x = 0~30 at.%) Shape Memory Alloys at a Low Frequency

نویسندگان

  • Chen Chien
  • Shyi-Kaan Wu
  • Shih-Hang Chang
چکیده

The damping characteristics of Ti50Ni50-xCux (x = 0~30 at.%) shape memory alloys (SMAs) at a low frequency have been studied using a dynamic mechanical analyzer. The magnitude of the tan δ value and the values of the storage modulus (E₀) softening/hardening and the strain variation exhibited in B2↔B19 transformation are all higher than those in B2↔B19' transformation. The larger E₀ softening/hardening in B2↔B19 can induce higher strain variation in this transformation. It is suggested that the greater mobility of the twin boundaries and the larger magnitude of the strain variation both cause the higher tan δ value exhibited in B2↔B19 transformation, as compared with B2↔B19' transformation. In comparison with that in B19' martensite, the E₀ value in B19 martensite is low and not affected so greatly by changes in temperature. Relaxation peaks are observed in B19' martensite, but not in B19 martensite, because the latter has rare twinned variants. The activation energy of the relaxation peak is calculated and found to increase as the Cu-content increases in these SMAs.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Martensitic transformation and shape memory effect in B2 intermetallic compounds of titanium

2014 Crystallographic and kinetic characteristics of martensitic transformations and parameters of shape memory effect in B2 compounds of titanium Ti50Ni50-xXx (X = Fe, Co, Pd, Pt, Au, Cu) and Ti50Pd50-xYx (Y = Fe, Co, Cu), where 0 ~ x ~ 50 are investigated. Temperature, hysteresis, value of reversible deformation and stress of martensitic shear for martensitic transformations and shape memory ...

متن کامل

Application of Shape Memory Alloys in Seismic Isolation: A Review

In the last two decades, there has been an increasing interest in structural engineering control methods. Shape memory alloys and seismic isolation systems are examples of passive control systems that use of any one alone, effectively improve the seismic performance of the structure. Characteristics such as large strain range without any residual deformation, high damping capacity, excellent re...

متن کامل

TRANSFORMATION BEHAVIOR OF NiTi SHAPE MEMORY ALLOYS TREATED BY THERMOMECHANICAL PROCESSING USING DSC

Abstract: In the present study the effect of thermomechanical treatment (cold work and annealing) on the transformation behavior of NiTi shape memory alloys was studied. Differential scanning calorimetry was used to determine transformation temperature and its relation to precipitates and defects. Three alloys including Ti-50.3at.% Ni, Ti-50.5at.% Ni (reclamated orthodontic wires) and 50.6at...

متن کامل

Damping Characteristics of Inherent and Intrinsic Internal Friction of Cu-Zn-Al Shape Memory Alloys

Damping properties of the inherent and intrinsic internal friction peaks (IFPT + IFI) of Cu-xZn-11Al (x = 7.0, 7.5, 8.0, 8.5, and 9.0 wt. %) shape memory alloys (SMAs) were investigated by using dynamic mechanical analysis. The Cu-7.5Zn-11Al, Cu-8.0Zn-11Al, and Cu-8.5Zn-11Al SMAs with (IFPT + IFI)β3(L21)→γ′ 3(2H) peaks exhibit higher damping capacity than the Cu-7.0Zn-11Al SMA with a (IFPT + IF...

متن کامل

A 3d Micro-Plane Model for Shape Memory Alloys

are compared with the experimental results. In these test results the shape memory alloys behavior as: super elasticity under various temperatures, loading rate effects, asymmetry in tension and pressure, various loops of loading and unloading, hydrostatic pressure effects, different proportional tension-shear biaxial loading and unloading, and also deviation from normality due to non-proportio...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 7  شماره 

صفحات  -

تاریخ انتشار 2014