Quantization Effect of Mechanical Energy Absorbed by Metals Under Deformation and Fracture

1989 ◽  
pp. 3731-3738
Author(s):  
YU.I. RAGOZIN
Keyword(s):  
Mechanical Energy ◽  
Quantization Effect ◽  
Deformation And Fracture

Environmental cell studies of deformation and fracture

1990 ◽  
Vol 48 (4) ◽  
pp. 516-517
Author(s):  
H. K. Birnbaum ◽  
I. M. Robertson
Keyword(s):  
National Laboratory ◽  
Argonne National Laboratory ◽  
Damage Threshold ◽  
Chromatic Aberration ◽  
Good Choice ◽  
Point Of View ◽  
Deformation And Fracture ◽  
Environmental Cell ◽  
Gas Molecules ◽  
The University

Studies of the effects of hydrogen environments on the deformation and fracture of fcc, bcc and hep metals and alloys have been carried out in a TEM environmental cell. The initial experiments were performed in the environmental cell of the HVEM facility at Argonne National Laboratory. More recently, a dedicated environmental cell facility has been constructed at the University of Illinois using a JEOL 4000EX and has been used for these studies. In the present paper we will describe the general design features of the JEOL environmental cell and some of the observations we have made on hydrogen effects on deformation and fracture.The JEOL environmental cell is designed to operate at 400 keV and below; in part because of the available accelerating voltage of the microscope and in part because the damage threshold of most materials is below 400 keV. The gas pressure at which chromatic aberration due to electron scattering from the gas molecules becomes excessive does not increase rapidly with with accelerating voltage making 400 keV a good choice from that point of view as well. A series of apertures were placed above and below the cell to control the pressures in various parts of the column.

Deformation and fracture behavior of an Al-Li-Cu-Mg-Zr alloy 8090

1990 ◽  
Vol 48 (4) ◽  
pp. 974-975
Author(s):  
D.M. Jiang ◽  
B.D. Hong
Keyword(s):  
High Strength ◽  
Deformation And Fracture ◽  
Fracture Behaviors ◽  
Aluminum Lithium ◽  
Carbon Fiber Reinforced Composites ◽  
Peak Aged ◽  
Aluminum Lithium Alloys ◽  
High Strength Aluminum Alloys ◽  
Lithium Alloys ◽  
Zr Alloy

Aluminum-lithium alloys have been recently got strong interests especially in the aircraft industry. Compared to conventional high strength aluminum alloys of the 2000 or 7000 series it is anticipated that these alloys offer a 10% increase in the stiffness and a 10% decrease in density, thus making them rather competitive to new up-coming non-metallic materials like carbon fiber reinforced composites.The object of the present paper is to evaluate the inluence of various microstructural features on the monotonic and cyclic deformation and fracture behaviors of Al-Li based alloy. The material used was 8090 alloy. After solution treated and waster quenched, the alloy was underaged (190°Clh), peak-aged (190°C24h) and overaged (150°C4h+230°C16h). The alloy in different aging condition was tensile and fatigue tested, the resultant fractures were observed in SEM. The deformation behavior was studied in TEM.

DYNAMIC STUDIES OF DEFORMATION AND FRACTURE AT GRAIN BOUNDARIES

1988 ◽  
Vol 49 (C5) ◽  
pp. C5-677-C5-680
Author(s):  
I. M. ROBERTSON ◽  
G. M. BOND ◽  
T. C. LEE ◽  
D. S. SHIH ◽  
H. K. BIRNBAUM
Keyword(s):  
Grain Boundaries ◽  
Dynamic Studies ◽  
Deformation And Fracture

Reduction of structural vibrations with the piezoelectric stacks ring

2020 ◽  
Vol 64 (1-4) ◽  
pp. 729-736
Author(s):  
Jincheng He ◽  
Xing Tan ◽  
Wang Tao ◽  
Xinhai Wu ◽  
Huan He ◽  
...  
Keyword(s):  
Vibration Control ◽  
Mechanical Energy ◽  
Electrical Energy ◽  
Structural Vibrations ◽  
Rotor Systems ◽  
Fea Model ◽  
Piezoelectric Stacks ◽  
Shunt Damping ◽  
Reduction Effect ◽  
Euler Bernoulli Beam

It is known that piezoelectric material shunted with external circuits can convert mechanical energy to electrical energy, which is so called piezoelectric shunt damping technology. In this paper, a piezoelectric stacks ring (PSR) is designed for vibration control of beams and rotor systems. A relative simple electromechanical model of an Euler Bernoulli beam supported by two piezoelectric stacks shunted with resonant RL circuits is established. The equation of motion of such simplified system has been derived using Hamilton’s principle. A more realistic FEA model is developed. The numerical analysis is carried out using COMSOL® and the simulation results show a significant reduction of vibration amplitude at the specific natural frequencies. Using finite element method, the influence of circuit parameters on lateral vibration control is discussed. A preliminary experiment of a prototype PSR verifies the PSR’s vibration reduction effect.

CLINICAL AND NEUROLOGICAL FEATURES OF TRAUMATIC BRAIN DISEASE DURING THE STAGES OF REHABILITATION

2020 ◽  
Vol 3 (1) ◽  
pp. 51-53
Author(s):  
Rano Azizova ◽  
◽  
Umida Shamsiyeva ◽  
Mirzohid Turabbayev ◽  
Begzod Jorayev ◽  
...  
Keyword(s):  
Mechanical Energy ◽  
Pathological Process ◽  
Brain Disease ◽  
Clinical Forms ◽  
Neurological Features ◽  
Mechanisms Of Development ◽  
The Brain

Traumatic brain disease (TBHD) is a pathological process triggered by the damaging effect of mechanical energy on the brain and is characterized — with a variety of clinical forms — by the unity of etiology, pathogenetic and sanogenetic mechanisms of development and outcomes.

Deformation and fracture of amorphous and crystalline wires of medical usage at torsion

2018 ◽  
pp. 36-44
Author(s):  
V. V. Molokanov ◽  
◽  
T. R. Chueva ◽  
P. P. Umnov ◽  
N. V. Umnova ◽  
...  
Keyword(s):  
Deformation And Fracture
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