Measurement of Young's modulus and internal friction of an in situ Al-Al3Ni functionally gradient material

1994 ◽  
Vol 29 (9) ◽  
pp. 2281-2288 ◽  
Author(s):  
Y. Fukui ◽  
K. Takashima ◽  
C. B. Ponton
Keyword(s):  
Internal Friction ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Gradient Material ◽  
Functionally Gradient Material ◽  
Functionally Gradient

STUDYING IN-SITU ON THE SUPERCONDUCTING TRANSITION AND INTERNAL FRICTION OF A HIGH Tc SUPERCONDUCTOR YBa2Cu307−δ

1988 ◽  
Vol 01 (11n12) ◽  
pp. 425-429 ◽  
Author(s):  
JIA-JU DU ◽  
JIAN-YI JIANG ◽  
XIANG WANG ◽  
HUA-QING YIN
Keyword(s):  
Internal Friction ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Electronic Relaxation ◽  
Superconducting Transition ◽  
High Tc ◽  
High Tc Superconductor ◽  
Two Peaks

The resistence, internal friction and modulus of a high Tc superconductor YBa2Cu3O7−δ were measured in-situ in 80–300 K. Two obvious peaks of internal friction were observed about Tc. On account of character of peaks, it is suggested that these two peaks are associated with the electronic relaxation between Cu3+ and Cu2+. The peak and anomalies of Young’s modulus observed in the range between 160 K and 280 K may be related to the adjustment of deficiency of oxygen.

Mechanical Properties of Pyrolytic "SiOCN" Thin Coatings

1993 ◽  
Vol 308 ◽  
Author(s):  
Sandrine Bec ◽  
André Tonck ◽  
Jean-Luc Loubet
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Ceramic Coatings ◽  
Optical Observation ◽  
Thin Coatings ◽  
Polymer Precursors ◽  
Polymeric State

ABSTRACTPyrolysis of polymer precursors (polysilazane) is a technologically and economically interesting way to produce thin ceramic coatings. However, many cracks appear and decohesion occurs during pyrolysis when the ceramic coatings (SiOCN) are thicker than 0.5 micrometers. In order to understand these cracking phenomena, the coatings are mechanically characterized by nanoindentation at different stages of the pyrolysis heat treatment.During pyrolysis, the cracking temperature is detected by in-situ optical observation. The thickness of the coatings varies during pyrolysis from 3 micrometers at the polymeric state to 1 micrometer at the ceramic state. The coatings' properties, hardness and Young's modulus are evaluated after heat treatment, taking into account the substrate's influence. A large variation of these properties occurs at the cracking temperature. Both the hardness and the Young's modulus are multiplied by a factor of 10. By analysing these results, we show that cracking is correlated with the evolution of the coatings' mechanical properties during the transformation.

scholarly journals Young’s Modulus of Polycrystalline Titania Microspheres Determined by In Situ Nanoindentation and Finite Element Modeling

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Peida Hao ◽  
Yanping Liu ◽  
Yuanming Du ◽  
Yuefei Zhang
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Deformation Mechanisms ◽  
Displacement Curve ◽  
Element Simulation ◽  
Nanoindentation Experiment ◽  
Force Displacement

In situ nanoindentation was employed to probe the mechanical properties of individual polycrystalline titania (TiO2) microspheres. The force-displacement curves captured by a hybrid scanning electron microscope/scanning probe microscope (SEM/SPM) system were analyzed based on Hertz’s theory of contact mechanics. However, the deformation mechanisms of the nano/microspheres in the nanoindentation tests are not very clear. Finite element simulation was employed to investigate the deformation of spheres at the nanoscale under the pressure of an AFM tip. Then a revised method for the calculation of Young’s modulus of the microspheres was presented based on the deformation mechanisms of the spheres and Hertz’s theory. Meanwhile, a new force-displacement curve was reproduced by finite element simulation with the new calculation, and it was compared with the curve obtained by the nanoindentation experiment. The results of the comparison show that utilization of this revised model produces more accurate results. The calculated results showed that Young’s modulus of a polycrystalline TiO2microsphere was approximately 30% larger than that of the bulk counterpart.

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