Effects of cobalt content on martensitic transformation and shape memory effect in Fe-Mn-Si-Cr-Ni alloys

2003 ◽  
Vol 112 ◽  
pp. 393-396
Author(s):  
B. Jiang ◽  
K. Xu ◽  
X. Qi ◽  
W. Zhou
2005 ◽  
Vol 475-479 ◽  
pp. 2029-2032 ◽  
Author(s):  
Wei Min Zhou ◽  
Yan Liu ◽  
Bohong Jiang ◽  
Xuan Qi

Co-Ni alloys exhibit g(fcc)®e(hcp) martensitic transformation and show reversible induced strain under applied magnetic field, which means they are potential magneto-shape-memory materials. Polystalline of Co-Ni alloys with varied Ni content were prepared. The g(fcc)®e(hcp) martensitic transformation and shape memory effect (SME) of Co-Ni alloy were studied. The influences of Ni content and deformation temperature on SME were discussed. The shape recovery rate and recoverable strain decrease with the increase of Ni content.


2005 ◽  
Vol 96 (8) ◽  
pp. 843-846 ◽  
Author(s):  
Yunqing Ma ◽  
Lihong Xu ◽  
Yan Li ◽  
Chengbao Jiang ◽  
Huibin Xu ◽  
...  

2017 ◽  
Vol 62 (2) ◽  
pp. 1367-1370 ◽  
Author(s):  
Y.-W. Kim ◽  
T.W. Mukarati

AbstractNon-toxic Ti-Nb-Mo scaffolds were fabricated by sintering rapidly solidified alloy fibers for biomedical applications. Microstructure and martensitic transformation behaviors of the porous scaffolds were investigated by means of differential scanning calorimetric and X-ray diffraction. Theα″–βtransformation occurs in the as-solidified fiber and the sintered scaffolds. According to the compressive test of the sintered scaffolds with 75% porosity, they exhibit good superelasticity and strain recovery ascribed to the stress-induced martensitic transformation and the shape memory effect. Because of the high porosity of the scaffolds, an elastic modulus of 1.4 GPa, which matches well with that of cancellous bone, could be obtained. The austenite transformation finishing temperature of 77Ti-18Nb-5Mo alloy scaffolds is 5.1°C which is well below the human body temperature, and then all mechanical properties and shape memory effect of the porous 77Ti-18Nb-5Mo scaffolds are applicable for bon replacement implants.


Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 901
Author(s):  
Jie Chen ◽  
Yonghao Zhang ◽  
Jiqiang Ge ◽  
Huabei Peng ◽  
Shuke Huang ◽  
...  

To improve the shape memory effect (SME) of 304 austenitic steel effectively and efficiently, thermomechanical cycling, comprising deformation at room temperature and annealing, was applied. The influences of cycle number and annealing temperature on the SME and microstructures in 304 austenitic steel were investigated by light microscope (LM), X-ray diffraction (XRD), and transmission electron microscope (TEM). The shape recovery ratio was remarkably improved from 16% to 40% after two thermomechanical cycles. The optimum annealing temperature was 833 K in the process of thermomechanical cycling. The improved SME by thermomechanical cycling was mainly related to stress-induced ε martensite rather than stress-induced α’ martensite. The reason is that thermomechanical cycling can not only promote the occurrence of the stress-induced γ→ε martensitic transformation, but also suppress the subsequently stress-induced ε→α′ transformation.


Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1890
Author(s):  
Anton I. Tagiltsev ◽  
Elena Y. Panchenko ◽  
Ekaterina E. Timofeeva ◽  
Yuriy I. Chumlyakov ◽  
Ekaterina S. Marchenko ◽  
...  

This study investigated the effect of stress-induced martensite aging under tensile and compressive stresses on the functional and viscoelastic properties in Ni50.3Ti32.2Hf17.5 polycrystals containing dispersed H-phase particles up to 70 nm in size obtained by preliminary austenite aging at 873 K for 3 h. It was found that stress-induced martensite aging at 428 K for 12 h results in the appearance of a two-way shape memory effect of −0.5% in compression and +1.8% in tension. Moreover, a significant change in viscoelastic properties can be observed: an increase in internal friction (by 25%) and a change in elastic modulus in tensile samples. The increase in internal friction during martensitic transformation after stress-induced martensite aging is associated with the oriented growth of thermal-induced martensite. After stress-induced martensite aging, the elastic modulus of martensite (EM) increased by 8 GPa, and the elastic modulus of austenite (EA) decreased by 8 GPa. It was shown that stress-induced martensite aging strongly affects the functional and viscoelastic properties of material and can be used to control them.


2018 ◽  
Vol 49 (4) ◽  
pp. 1044-1052 ◽  
Author(s):  
X. Yang ◽  
B. N. Qian ◽  
H. B. Peng ◽  
B. J. Wu ◽  
Y. H. Wen

Sign in / Sign up

Export Citation Format

Share Document