Cracking creep

R. Thomson, Lattice theory of fracture and crack creep, J. Appl. Phys. 44 (1973) 2051-2063. 

Specifications should include any specific properties required for the application, such as resilience, hysteresis, static or dynamic shear and compression modulus, flex fatigue and cracking, creep resistance to oils and chemicals, permeability, and brittle point, all in the temperature ranges to be encountered in service. 

Low-temperature cracking When the pavement temperature decreases, asphalt pavement shrinks. Since friction against the lower pavement layer inhibits movement, tensile stresses buildup in the pavement When these stresses exceed the tensile strength of the asphalt mix, a low temperature crack occurs. The bending beam rheometer is used to apply a small creep load to a binder beam specimen and measure the creep stiffness. If the creep stiffness is too high, the asphalt will behave in a brittle maimer, and cracking is more likely to occur. To prevent this cracking, creep stiffness has a maximum limit of 300 MPa. 

Environmental stress cracking, creep test, increasing... 

The properties of a single crystal creeping wave probe The a single crystal creeping wave probe is suitable for testing various artificial defects such as surface cracks, FBH, columned hole and SDH etc. and its distance amplitude cruve is shown in Fig.6... 

Besides, because this probe is suitable for testing various artificial defects such as FBH, SDH, columned holes and cracks and its testing range is larger than ordinary one-transmitting-and-the-other-receiving double crystal creeping wave probe, we can conclude that this probe has a wide use value and prospect. 

BE-74E3 Creep crack growth in carbon- manganese steel at 300 420 Mr. R. Maskel BABCOCK ENERGY Ltd... 

SMT-2070 Development of creep crack growth testing and data analyses procedures for Dr. Bilal Dogan GKSS... 

Plate with a crack under the creep condition... 

We consider a boundary value problem for equations describing an equilibrium of a plate being under the creep law (1.31)-(1.32). The plate is assumed to have a vertical crack. As before, the main peculiarity of the problem is determined by the presence of an inequality imposed on a solution which represents a mutual nonpenetration condition of the crack faces... 

Khludnev A.M. (1996c) On equilibrium problem for a plate having a crack under the creep condition. Control and Cybernetics 25 (5), 1015-1029. 

The material in use as of the mid-1990s in these components is HDPE, a linear polymer which is tough, resiUent, ductile, wear resistant, and has low friction (see Olefin polymers, polyethylene). Polymers are prone to both creep and fatigue (stress) cracking. Moreover, HDPE has a modulus of elasticity that is only one-tenth that of the bone, thus it increases the level of stress transmitted to the cement, thereby increasing the potential for cement mantle failure. When the acetabular HDPE cup is backed by metal, it stiffens the HDPE cup. This results in function similar to that of natural subchondral bone. Metal backing has become standard on acetabular cups. 

Master curves can be used to predict creep resistance, embrittlement, and other property changes over time at a given temperature, or the time it takes for the modulus or some other parameter to reach a critical value. For example, a mbber hose may burst or crack if its modulus exceeds a certain level, or an elastomeric mount may fail if creep is excessive. The time it takes to reach the critical value at a given temperature can be deduced from the master curve. Frequency-based master curves can be used to predict impact behavior or the damping abiUty of materials being considered for sound or vibration deadening. The theory, constmction, and use of master curves have been discussed (145,242,271,277,278,299,300). 

Four modes of characterization are of interest chemical analyses, ie, quaUtative and quantitative analyses of all components mechanical characterization, ie, tensile and impact testing morphology of the mbber phase and rheology at a range of shear rates. Other properties measured are stress crack resistance, heat distortion temperatures, flammabiUty, creep, etc, depending on the particular appHcation (239). 

Sintered sihcon carbide retains its strength at elevated temperatures and shows excellent time-dependent properties such as creep and slow crack growth resistance. Reaction-bonded SiC, because of the presence of free sihcon in its microstmcture, exhibits slightly inferior elevated temperature properties as compared to sintered sihcon carbide. Table 2 (11,43) and Table 3 (44) show selected mechanical properties of sihcon carbide at room and elevated temperatures. 

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