Constitutive Equation for 7050 Aluminum Alloy at High Temperatures

2006 ◽  
Vol 532-533 ◽  
pp. 125-128 ◽  
Author(s):  
Xiu Li Fu ◽  
Xing Ai ◽  
Song Zhang ◽  
Yi Wan

Accurately material constitutive model is essential to understand and predict machining process. High temperature split Hopkinson pressure bar (SHPB) test system is used to investigate flow stress behavior and characteristics of 7050-T7451 aluminum alloy. Specimens are tested from 200°C to 550°C at intervals of 50°C and room temperature, at strain-rate of 2800s-1. The experimental results show that flow stress is strongly dependent on temperature as well as strain rate, flow stress decreases with the increase of temperature, while increase with the increasing of strain rate. The material parameters are determined for both Johnson-Cook constitutive equation and modified Johnson-Cook constitutive equation. The modified JC equation is more suitable for expressing the dynamic behavior of 7050-T7451 aluminum alloy.

2013 ◽  
Vol 535-536 ◽  
pp. 497-500 ◽  
Author(s):  
Zhi Wu Zhu ◽  
Guo Zheng Kang ◽  
Dong Ruan ◽  
Yue Ma ◽  
Guo Xing Lu

5083 aluminum alloy was investigated with respect to its uniaxial dynamic compressive properties over a range of strain rates using the split Hopkinson pressure bar (SHPB). The dynamic stress-strain curves of this alloy were obtained for strain rates from 1000 s-1 to 6000 s-1. Effects of strain rate, the samples size and anti-impact capability were analyzed. The experimental results show that under impaction loading, 5083 aluminum alloy has a remarkable strengthening response to strain rate and size; in particular, the responded stress increases with increasing strain rate, which implies that this alloy has high strength and high anti-impact capability.


2015 ◽  
Vol 816 ◽  
pp. 795-803
Author(s):  
Yan Ling Wang ◽  
Song Xiao Hui ◽  
Wen Jun Ye ◽  
Rui Liu

The mechanical properties and fracture failure behavior of the near β-type Ti-5Al-5Mo-5V-3Cr-X (X = 1Fe or 1Zr) titanium alloys were studied by Split Hopkinson Pressure Bar (SHPB) experiment under the dynamic loading conditions at a strain rate of 1.5 × 103 s-1–5.0 × 103 s-1. Results showed that the SHPB specimen fractured in the direction of maximum shearing stress at an angle of 45° with the compression axis. The fracture surface revealed the shear and tension zones with cleavage steps and parabolic dimples. Severe early unloading was observed on the Ti-5553 alloy under a strain rate of 4,900 s-1 loading condition, and the dynamic property of the Ti-55531Zr alloy was proved to be the optimal.


2021 ◽  
Vol 1035 ◽  
pp. 591-595
Author(s):  
Dan Guo ◽  
Jian Ming Liu ◽  
De Ming Zhang ◽  
Xin Zhang ◽  
Tong Liu

The purpose of this investigation is to study the dynamic hardness of MCrAlY abradable coatings under different strain rates. A dynamic indentation device based on the split Hopkinson pressure bar system (SHPB) was used. The results show that the hardness of MCrAlY coating increased with the increase of the strain rate, which has a positive strain rate effect. In addition, the difference of the static hardness of MCrAlY coating prepared by HVOF and LPPS was only 4%, while the difference in dynamic hardness was 16%.


2018 ◽  
Vol 183 ◽  
pp. 04005 ◽  
Author(s):  
Bar Nurel ◽  
Moshe Nahmany ◽  
Adin Stern ◽  
Nahum Frage ◽  
Oren Sadot

Additive manufacturing by Selective Laser Melting of metals is attracting substantial attention, due to its advantages, such as short-time production of customized structures. This technique is useful for building complex components using a metallic pre-alloyed powder. One of the most used materials in AMSLM is AlSi10Mg powder. Additively manufactured AlSi10Mg may be used as a structural material and it static mechanical properties were widely investigated. Properties in the strain rates of 5×102–1.6×103 s-1 and at higher strain rates of 5×103 –105 s-1 have been also reported. The aim of this study is investigation of dynamic properties in the 7×102–8×103 s-1 strain rate range, using the split Hopkinson pressure bar technique. It was found that the dynamic properties at strain-rates of 1×103–3×103 s-1 depend on a build direction and affected by heat treatment. At higher and lower strain-rates the effect of build direction is limited. The anisotropic nature of the material was determined by the ellipticity of samples after the SHPB test. No strain rate sensitivity was observed.


2013 ◽  
Vol 816-817 ◽  
pp. 84-89
Author(s):  
Yong Gang Kang ◽  
Yuan Yang ◽  
Jie Huang ◽  
Jing Hang Zhu

7075-T651 aluminum alloy are widely used in aeronautical applications such as wing panels, but there is no corresponding constitutive model for it now. In this paper, the flow behavior of 7050-T651 aluminum alloy was investigated by Split Hopkinson Pressure Bar (SHPB) and quasi-static compression experiment system. The strain hardening parameters were obtained by quasi-static compression experiment data, and the strain rate hardening parameters at various strain rates (1000-3000s-1) and room temperature, and the thermal softening parameter at various temperatures (20-300°C) where strain rate is 3000s-1 were obtained by SHPB experiment data. Then the constitutive equation of 7075-T651 aluminum alloy is obtained based on Johnson-Cook constitutive equation model.


2011 ◽  
Vol 284-286 ◽  
pp. 1542-1545 ◽  
Author(s):  
Qing Wen Ding ◽  
Yu Ren ◽  
Cheng Wen Tan ◽  
Jing Zhang ◽  
Xiao Dong Yu

A Split Hopkinson Pressure Bar system was employed to investigate the compressive dynamic mechanical behaviors of Ti-10V-2Fe-3Al (Ti-1023) alloy with lamellar microstructure, over a broad strain rates ranging from 1500/s to 5100/s. The results reveal that the strain rate has a significant effect on the flow stress of Ti-1023 alloy, and there exists serious thermal softening as the strain rate exceeds 3200/s. The critical strain rate of fracture for this alloy is 2300/s. The microstructure examination indicated that adiabatic shear bands (ASBs) bifurcate more intensely with the increasing of strain rate. Micro-voids nucleate either in the ASB or interface between shear band and matrix bulk. Finally, fracture of this alloy proceeds through the nucleation, growth and coalescence of these voids and cracks along the ASBs.


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