Mechanical Properties of (Pt, Ir)Ti

2005 ◽  
Vol 475-479 ◽  
pp. 1987-1990 ◽  
Author(s):  
Yoko Yamabe-Mitarai ◽  
Toru Hara ◽  
Seiji Miura ◽  
Hideki Hosoda

We have suggested B2-(Pt, Ir)Ti as high temperature shape memory alloys. The phase transformation of (Pt, Ir)-50at% Ti from B2 to B19(2H) or 4H(4O) structures was investigated in our previous study. The microstructure suggested martensitic transformation. In this study, thermal expansion measurement and cyclic compression test were performed for (Pt, Ir)Ti to investigate if the shape memory effect appears. High temperature strength was also investigated because phase transformation temperature of the (Pt, Ir)Ti is above 1273 K and high strength is necessary as high temperature shape memory alloys in order to suppress dislocation motion and stabilize martenstic transformation. The potential of (Pt, Ir)Ti as high temperature shape memory alloys will be also discussed.

2014 ◽  
Vol 783-786 ◽  
pp. 2541-2545 ◽  
Author(s):  
Yoko Yamabe-Mitarai ◽  
Abdul Wadood ◽  
Raju Arockiakumar ◽  
Toru Hara ◽  
Madoka Takahashi ◽  
...  

The effect of alloying to TiPd and TiPt on phase transformation temperature, phase equilibria, and shape recovery were investigated for TiPt and TiPd base high-temperature shape memory alloys. Ru, Ir, Co and Zr were chosen for additional elements and Zr was found as the most effective element to improve shape recovery of TiPd and TiPt.


2005 ◽  
Vol 13 (2) ◽  
pp. 197-201 ◽  
Author(s):  
X.L. Meng ◽  
W. Cai ◽  
K.T. Lau ◽  
L.C. Zhao ◽  
L.M. Zhou

2015 ◽  
Vol 833 ◽  
pp. 67-70
Author(s):  
Shui Yuan Yang ◽  
Cui Ping Wang ◽  
Yu Su ◽  
Xing Jun Liu

The evolutions of microstructure and phase transformation behavior of Cu-Al-Fe-Nb/Ta high-temperature shape memory alloys under the quenched and aged states were investigated in this study, including Cu-10wt.% Al-6wt.% Fe, Cu-10wt.% Al-4wt.% Fe-2wt.% Nb and Cu-10wt.% Al-4wt.% Fe-2wt.% Ta three types alloys. The obtained results show that after quenching, Cu-10wt.% Al-6wt.% Fe alloy exhibits two-phase microstructure of β′1 martensite + Fe (Al,Cu) phase; Cu-10wt.% Al-4wt.% Fe-2wt.% Nb alloy also has two-phase microstructure of (β′1 + γ′1 martensites) + Nb (Fe,Al,Cu)2 phase; Cu-10wt.% Al-4wt.% Fe-2wt.% Ta alloy is consisted of three-phase of (β′1 + γ′1 martensites) + Fe (Al,Cu,Ta) + Ta2(Al,Cu,Fe)3 phases. However, α (Cu) phase precipitates after aging for three alloys; and Fe (Al,Cu,Nb) phase is also present in Cu-10wt.% Al-4wt.% Fe-2wt.% Nb alloy. All the studied alloys exhibit complicated martensitic transformation behaviors resulted from the existence of two types martensites (β′1 and γ′1).


2015 ◽  
Vol 833 ◽  
pp. 63-66
Author(s):  
Cui Ping Wang ◽  
Yu Ding Liu ◽  
Shui Yuan Yang ◽  
Xing Jun Liu

The microstructure and phase transformation behavior of Ni-Mn-Fe high-temperature shape memory alloys including Ni40+xFe10Mn50-x (x = 0, 10) were investigated. The results show that both two alloys exhibit single fcc γ phase annealed at 900°C for 1 day. When these quenched alloys are again annealed at 500°C for 20 days, they almost exhibit main tetragonal θ martensite. The microstructural evolutions are consistent with the results of phase transformation measurements. It is clearly found that there is an irreversible phase transformation around 480°C ~ 570°C, which is associated with the formation of tetragonal θ martensite from γ phase. Afterwards, the reversible martensitic transformation occurs during heating and cooling with very high transformation temperature.


2014 ◽  
Vol 775-776 ◽  
pp. 112-117
Author(s):  
G.C.S. Anselmo ◽  
Walmam B. de Castro ◽  
C.J. de Araújo

Shape memory alloys (SMAs) represent a unique class of materials that undergo a reversible phase transformation (martensitic transformation) allowing these materials to display dramatic pseudoelastic stress-induced deformations and shape memory temperature-induced deformations that are recoverable. Among the known shape memory alloys, NiTi is the most commonly used because of its excellent mechanical properties, corrosion resistance and biocompatibility. This work studied the influence of two parameters of heat treatment (temperature and time) on martensite phase transformation temperature (MS) in a Ni-Ti (48,8 wt % Ti) shape memory alloy, using a factorial design (22). The aim of our research was to establish a mathematic model of the technological process, useful for controlling of martensite phase transformation temperature. The two factors, temperature and time, have an important influence on MS.


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