Temperature and Strain Rate Dependence of Mechanical Properties and Square Shell Deep Drawability of Al-Mg Alloy Sheets in Warm Working Condition

Foamed plastics have been used in many engineering fields because of their superiority in low density, energy absorption, thermal insulation, and acoustic damping capacities. With foams, it is known that the microstructure of cells directly relates to macroscopic deformation behaviour. However, mechanical properties based on microstructures composed of non-uniform cells have not been fully understood. This study aims to clarify the mechanical properties grounded on microstructures of foamed plastics subjected to dynamic loading. The quasi-static and dynamic compression test was carried out using foamed plastic with anisotropy in the cell structure, then the strain rate dependence of deformation and energy absorption characteristics was investigated. It was confirmed that the local buckling of the cells was the dominant deformation mode in the plastic collapse of the test piece. It was also confirmed that cell buckling was initiated around the middle in the height after the plastic collapse, then propagated to the whole specimen in both the quasi-static and dynamic tests by using digital image correlation. The stress-strain relationships and the amount of absorbed energy showed strain rate dependence owing to the deformation mode in which the local buckling of the cells is dominant.

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STRAIN RATE DEPENDENCE ON MECHANICAL PROPERTIES IN SOME COMMERCIAL ALUMINUM ALLOYS

Journal de Physique IV (Proceedings) ◽

10.1051/jp4:1991349 ◽

1991 ◽

Vol 01 (C3) ◽

pp. C3-341-C3-346 ◽

Cited By ~ 3

Author(s):

K. HIGASHI ◽

T. MUKAI ◽

K. KAIZU ◽

S. TSUCHIDA ◽

S. TANIMURA

Keyword(s):

Mechanical Properties ◽

Aluminum Alloys ◽

Strain Rate ◽

Rate Dependence ◽

Strain Rate Dependence

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Strain rate-dependence of mechanical properties of welded topopah spring tuff

International Journal of Rock Mechanics and Mining Sciences ◽

10.1016/j.ijrmms.2003.12.052 ◽

2004 ◽

Vol 41 (3) ◽

pp. 395 ◽

Cited By ~ 3

Author(s):

Lumin Ma ◽

J.J.K. Daemen

Keyword(s):

Mechanical Properties ◽

Strain Rate ◽

Rate Dependence ◽

Strain Rate Dependence ◽

Topopah Spring Tuff

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Dynamic behaviour of Al-Mg aluminum alloy at a wide range of strain rates

EPJ Web of Conferences ◽

10.1051/epjconf/201818302028 ◽

2018 ◽

Vol 183 ◽

pp. 02028

Author(s):

Tsuyoshi Kami ◽

Hiroyuki Yamada ◽

Nagahisa Ogasawara

Keyword(s):

Strain Rate ◽

Pure Aluminum ◽

Testing Machine ◽

Rate Dependence ◽

Strain Rate Dependence ◽

Mg Alloy ◽

Strain Rates ◽

Positive Strain ◽

Wide Range ◽

The Impact

The effect of strain rate on mechanical properties of Al-2.3wt.%Mg alloy (AA5021) and commercial pure aluminum (purity 99.7wt.%: A1070) was investigated at room temperature. The tensile tests were conducted at strain rates from 1.0×10−4 to 1.0×103 s−1. The universal testing machine was used for strain rate 1.0×10-4 to 1.0×10−1 s−1. For the strain rate 1.0×100 s-1, the servohydraulic testing machine, which was developed by our laboratory, was used. The impact strain rate 1.0×103 s−1 was obtained using the split Hopkinson pressure bar method. The pure aluminum showed positive strain rate dependence of material strength at the investigated strain rates. In contrast, the Al-2.3wt.%Mg alloy showed the negative strain rate dependence at strain rates from 1.0×10−4 to 1.0×100 s−1. However, Al-2.3wt.%Mg alloy showed the positive strain rate dependence at strain rates from 1.0×100 to 1.0×103 s−1. It was surmised that the effect of dislocation locking by the solute Mg atoms became negligible at strain rate of approximately 1.0×100 s−1. It was confirmed that material properties for the Al-Mg alloy at the strain rate of 1.0×100 s−1 were important, since the strain rate dependence changed negative to positive around this strain rate.

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