Nonequilibrium tensile deformation of amorphous polymers in the rubbery state: Temperature, strain rate, and strain effects. I

Tensile deformation behavior and microstructure of nickel-base superalloy Inconel 625 are investigated under different strain rates of 5 × 10−4 s−1 and 5 × 10−5 s−1. According to the experimental results, yield strength and ultimate tensile strength of the alloy increase with the increase in strain rate in room temperature. Microstructure results indicate that the size of dimples is smaller in the tensile fracture surface at low strain rate than the high strain rate, and the number of dimples is also related to the strain rates and twins appear earlier in the specimens with higher strain rates. Apart from Hollomon and Ludwik functions, a new formula considering the variation trend of strength in different deformation stages is deduced and introduced, which fit closer to the tensile curves of the 625 alloy used in the present work at both strain rates. Furthermore, the Schmid factors of tensile samples under two strain rates are calculated and discussed. In the end, typical work hardening behavior resulting from the dislocations slip behavior under different strain rates is observed, and a shearing phenomenon of slip lines cross through the δ precipitates due to the movement of dislocations is also be note.

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The effect of strain rates on tensile deformation of ultrafine-grained copper

International Journal of Modern Physics B ◽

10.1142/s0217979217440143 ◽

2017 ◽

Vol 31 (16-19) ◽

pp. 1744014

Author(s):

M. Li ◽

Q. W. Jiang

Keyword(s):

Strain Rate ◽

Deformation Behavior ◽

Room Temperature ◽

Tensile Deformation ◽

Strain Rates ◽

Roll Bonding ◽

Fracture Elongation ◽

Tensile Deformation Behavior ◽

Ultrafine Grained ◽

Flow Stress Level

Tensile deformation behavior of ultrafine-grained (UFG) copper processed by accumulative roll-bonding (ARB) was studied under different strain rates at room temperature. It was found that the UFG copper under the strain rate of 10[Formula: see text] s[Formula: see text] led to a higher strength (higher flow stress level), flow stability (higher stress hardening rate) and fracture elongation. In the fracture surface of the sample appeared a large number of cleavage steps under the strain rate of 10[Formula: see text] s[Formula: see text], indicating a typical brittle fracture mode. When the strain rate is 10[Formula: see text] or 10[Formula: see text] s[Formula: see text], a great amount of dimples with few cleavage steps were observed, showing a transition from brittle to plastic deformation with increasing strain rate.

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Effects of temperature, strain rate and glass surface treatment on the flexural properties of glass fiber-epoxy composites.

KOBUNSHI RONBUNSHU ◽

10.1295/koron.47.741 ◽

1990 ◽

Vol 47 (9) ◽

pp. 741-748 ◽

Cited By ~ 1

Author(s):

Masaki KIMOTO

Keyword(s):

Strain Rate ◽

Surface Treatment ◽

Glass Fiber ◽

Glass Surface ◽

Epoxy Composites ◽

Flexural Properties ◽

Effects Of Temperature ◽

Temperature Strain

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High Temperature Deformation Mechanism Maps of NiAl

Materials Science Forum ◽

10.4028/www.scientific.net/msf.449-452.57 ◽

2004 ◽

Vol 449-452 ◽

pp. 57-60

Author(s):

I.G. Lee ◽

A.K. Ghosh

Keyword(s):

High Temperature ◽

Strain Rate ◽

Deformation Mechanism ◽

Calculation Method ◽

Deformation Behavior ◽

Tensile Tests ◽

High Temperature Deformation ◽

Temperature Deformation ◽

Grain Sizes ◽

Temperature Strain

In order to analyze high temperature deformation behavior of NiAl alloys, deformation maps were constructed for stoichiometric NiAl materials with grain sizes of 4 and 200 µm. Relevant constitute equations and calculation method will be described in this paper. These maps are particularly useful in identifying the location of testing domains, such as creep and tensile tests, in relation to the stress-temperature-strain rate domains experienced by NiAl.

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