Tensile creep behaviour of polymethylpentene-silica nanocomposites

Microstructure and tensile creep behaviour of the die-cast AE44 and AJ62 magnesium alloys has been studied at temperatures between 175°C and 200°C and at stresses in the range from 60 to 75 MPa. At the 175°C the AJ62 and AE44 alloys exhibit good creep resistance after 120h creep deformation. At 200°C the AE44 alloy shows still good creep resistance, whereas in the case of AJ62 alloy the rapid decreasing of creep resistance has been observed. TEM observations reveal dislocations cell structure in AE44 alloy after creep test. In AJ62 alloy subgrain formation and decreasing the dislocation density have been observed.

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A Reference Stress Approach to Creep Bending of Straight Tubes

Journal of Mechanical Engineering Science ◽

10.1243/jmes_jour_1974_016_026_02 ◽

1974 ◽

Vol 16 (3) ◽

pp. 125-138 ◽

Cited By ~ 2

Author(s):

J. Fairbairn

Keyword(s):

Entire Range ◽

Creep Behaviour ◽

Tensile Creep ◽

Bending Moments ◽

Stress Distributions ◽

Creep Tests ◽

Reference Stress ◽

Hyperbolic Sine ◽

Rotation Method ◽

Reference Stress Approach

Reference-stress parameters, based on the Norton constitutive equation, are developed for creep bending of circular and elliptical tubes. The parameters are presented in the form of a design chart. The reference stress methods apply also to other simple constitutive equations of the power law, exponential and hyperbolic sine forms, and also to two complex equations describing creep behaviour over the entire range from primary to tertiary. In these equations the functions of stress and time are not separable and reference stress techniques provide a convenient method of evaluating stationary stress distributions and investigating the variation of these stresses with time. Aluminium alloy tubes were creep tested with cyclic uniform bending moments. Creep strains to fracture were measured by an end-rotation method. The creep behaviour of the tubes was well predicted by reference-stress cyclic tensile creep tests.

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Development of Creep Damage in Similar Weld Joints of P92 Steel Pipe

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.270.162 ◽

2017 ◽

Vol 270 ◽

pp. 162-167

Author(s):

Petr Král ◽

Vaclav Sklenička ◽

Květa Kuchařová ◽

Marie Svobodová ◽

Marie Kvapilová ◽

...

Keyword(s):

Welded Joints ◽

Creep Behaviour ◽

Creep Damage ◽

Electron Back Scatter Diffraction ◽

Steel Pipe ◽

Tensile Creep ◽

Creep Tests ◽

P92 Steel ◽

Welding Technology ◽

Fracture Ductility

The microstructure and creep behaviour of the welded joints of P92 steel pipe were investigated in order to determine the influence of orbital heat welding technology on the creep resistance. Creep specimens were machined from the welded joints. Tensile creep tests of welded joints were performed at 873 K using different stresses. The microstructure of tested specimens was investigated by scanning electron microscope Tescan equipped with an electron-back scatter diffraction. The creep results showed that the creep fracture strain of the welded joints decreases with decreasing value of applied stress. Microstructure investigation showed that fracture behaviour of welded joints is influenced by an enhanced cavity formation at grain boundaries in the heat-affected zone causing lower fracture ductility.

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Tensile creep behaviour of NiAl-Cr(Zr) multiphase intermetallic alloy

Materials Science and Technology ◽

10.1179/026708303225009689 ◽

2003 ◽

Vol 19 (3) ◽

pp. 399-402 ◽

Cited By ~ 24

Author(s):

Y. H. Qi ◽

J. T. Guo ◽

C. Y. Cui

Keyword(s):

Creep Behaviour ◽

Intermetallic Alloy ◽

Tensile Creep

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Influence of additions of Sb and/or Sr on microstructure and tensile creep behaviour of squeeze-cast AZ91D Mg alloy

Materials Science and Engineering A ◽

10.1016/j.msea.2016.12.006 ◽

2017 ◽

Vol 683 ◽

pp. 37-45 ◽

Cited By ~ 12

Author(s):

Punit Kumar ◽

A.K. Mondal ◽

S.G. Chowdhury ◽

G. Krishna ◽

Ashok Kumar Ray

Keyword(s):

Creep Behaviour ◽

Mg Alloy ◽

Tensile Creep ◽

Squeeze Cast

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Evaluation of Recycled Aggregate Concrete Cracking through Ring Test

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.174-177.1475 ◽

2012 ◽

Vol 174-177 ◽

pp. 1475-1480 ◽

Cited By ~ 6

Author(s):

Valeria Corinaldesi ◽

Giacomo Moriconi

Keyword(s):

Numerical Models ◽

Creep Behaviour ◽

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Tensile Creep ◽

Ring Test ◽

Early Age ◽

Concrete Aggregate ◽

Free Shrinkage

Cracks can reduce the service life of a concrete structure by allowing aggressive agents to penetrate through it in easy ways. Free shrinkage evaluation alone is not enough to determine if cracking can be expected in a structure since concrete creep behaviour, stiffness and toughness also influence the potential for cracking. Consequently, it is rather interesting to perform restrained shrinkage tests, such as the ring test according to ASTM C 1581–04. The testing procedure involves concrete ring specimens restrained by an inner steel ring on which strain gauges are placed to determine the age of cracking, since abrupt changes in the steel strain occur when concrete is cracked. Both the ring test and free shrinkage test should be carried out in the same exposure conditions, 21°C and 50% relative humidity. Moreover, compressive and tensile strengths of concrete were evaluated on cubic specimens at the time of its cracking and up to 28 days of curing. By means of analytical and numerical models of the ring specimen, some useful information on the stress induced in the material and on the tensile creep behaviour of concrete can be extrapolated thus allowing to better interpret the experimental results. This experimental procedure enables to study the influence of concrete mixture composition on the potential for early-age cracking of concrete. In particular, in this work the influence on early-age cracking of recycled-concrete aggregate partially replacing virgin sand was tested.

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