An experimental study on dynamic mechanical property ofultra-light aluminum foam under high temperatures
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摘要: 对传统的分离式Hopkinson压杆装置加以改进，设计了一种长杆直接撞击Hopkinson杆的实验方案，检测出低波阻抗材料在高温动态加载下的应力均匀性。对轻质泡沫铝材料的实验表明，在同一撞击速度下，温度越高，试件两端的应力均匀性越差，增加温度与提高撞击速度均会导致泡沫铝材料冲击端与支撑端的应力不均匀性。根据高温下应力均匀性的实验结果，确定高温下试件均匀变形对应的冲击速度，再通过传统的分离式Hopkinson压杆实验得出泡沫铝在高温动态下的力学性能。Abstract: An improved split Hopkinson pressure bar device was applied and a direct impact Hopkinson experimental program with long bullets was designed to measure the dynamic properties of closed-cell aluminum foam under high temperatures. Stress-time curves of both ends of aluminum foam specimens were obtained. It is found that the temperature markedly influence the stress uniformity of the specimens. As the temperature increases, the stress non-uniformity in the specimen becomes serious under the same impact velocity. Thus, both the increment in the test temperature and the impact velocity will cause stress non-uniformity of aluminum foam specimens. For aluminum foams, homogeneous deformation mode is dominant when the impact velocity is low, and the meso-scopic deformation pattern may vary but the stress field of the foam specimen is macroscopically homogeneous. Finally, the SHPB experiment is used to obtain the stress-strain curve under high temperature and high strain rate, after ensuring homogeneous deformation of the specimen.
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Key words:
- solid mechanics /
- stress uniformity /
- Hopkinson bar /
- ultra-light aluminum foam /
- high temperature /
- dynamic
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图 4 不同撞击速度下的两端应力曲线(25 ℃)
Figure 4. Stress curves of two ends under different impact velocity (25 ℃)
图 5 不同撞击速度下的两端应力曲线(350 ℃)
Figure 5. Stress curves of two ends under different impact velocity (350 ℃)
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[1] Deshpande V S, Fleck N A. High strain rate compressive behaviour of aluminium alloy foams[J]. International Journal of Impact Engineering, 2000, 24: 277-298. doi: 10.1016/S0734-743X(99)00153-0 [2] Dannemann K A, James L J. High strain rate compression of closed-cell aluminium foams[J]. Materials Science and Engineering: A, 2000, 293: 157-164. doi: 10.1016/S0921-5093(00)01219-3 [3] Hakamada M, Nomura T, Yamada Y, et al. Compressive deformation behavior at elevated temperatures in a closed-cell aluminum foam[J]. Materials Transactions, 2005, 46(7): 1677-1680. doi: 10.2320/matertrans.46.1677 [4] Cady C M, Gray Ⅲ G T, Liu C, et al. Compressive properties of a closed-cell aluminum foam as a function of strain rate and temperature[J]. Materials Science and Engineering: A, 2009, 525: 1-6. doi: 10.1016/j.msea.2009.07.007 [5] Chen Wei-nong, Song Bo. Split Hopkinson(Kolsky)bar: Design, testing and applications[M]. Springer, 2011. [6] Tan P J, Harrigan J J, Reid S R. Inertia effects in uniaxial dynamic compression of a closed cell aluminium alloy foam[J]. Materials Science and Technology, 2002, 18: 480-488. doi: 10.1179/026708302225002092 [7] Lopatnikov S L, Gama B A, Haque M J, et al. Dynamics of metal foam deformation during Taylor cylinder-Hopkinson bar impact experiment[J]. Composite Structures, 2003, 61: 61-71. doi: 10.1016/S0263-8223(03)00039-4 [8] Song B, Chen W. Dynamic stress equilibration in split Hopkinson pressure bar tests on soft materials[J]. Experimental Mechanics, 2004, 44(3): 300-312. doi: 10.1007/BF02427897 [9] Liu Y D, Yu J L, Zheng Z J, et al. A numerical study on the rate sensitivity of cellular metal[J]. International Journal of Solids and Structures, 2009, 46: 3988-3998. doi: 10.1016/j.ijsolstr.2009.07.024 [10] 王鹏飞, 胡时胜.轴向尺寸对泡沫铝动静态力学性能的影响[J].爆炸与冲击, 2012, 32(4): 393-398. doi: 10.3969/j.issn.1001-1455.2012.04.008Wang Peng-fei, Hu Shi-sheng. The mechanics property of foam aluminum with different sizes[J]. Explosion and Shock Waves, 2012, 32(4): 393-398. doi: 10.3969/j.issn.1001-1455.2012.04.008 [11] 王鹏飞, 徐松林, 胡时胜.变形模式对多孔金属材料SHPB实验结果的影响[J].力学学报, 2012, 44(5): 928-932. http://d.wanfangdata.com.cn/Periodical/lxxb201205014Wang Peng-fei, Xu Song-lin, Hu Shi-sheng. Influence of deformation modes on SHPB experimental results of cellular metal material[J]. Chinese Journal of Theoretical and Applied Mechanics, 2012, 44(5): 928-932. http://d.wanfangdata.com.cn/Periodical/lxxb201205014 [12] 周国才, 胡时胜, 付峥.用于测量材料高温动态力学性能的SHPB技术[J].实验力学, 2010, 25(1): 9-15.Zhou Guo-cai, Hu Shi-sheng, Fu Zheng. SHPB technique used for measuring dynamic properties of material in high temperature[J]. Journal of Experimental Mechanics, 2010, 25(1): 9-15. [13] Yang L M, Shim V. An analysis of stress uniformity in split Hopkinson bar test specimens[J]. International Journal of Impact Engineering, 2005, 31(2): 129-150. doi: 10.1016/j.ijimpeng.2003.09.002 [14] Ravichandran G, Subhash G. Critical appraisal of limiting strain rates for compression testing of ceramics in a split Hopkinson pressure bar[J]. Journal of the American Ceramic Society, 1994, 77(1): 263-267. doi: 10.1111/j.1151-2916.1994.tb06987.x [15] 宋力, 胡时胜. SHPB测试中的均匀性问题及恒应变率[J].爆炸与冲击, 2005, 25(3): 207-216. doi: 10.3321/j.issn:1001-1455.2005.03.003Song Li, Hu Shi-sheng. Stress uniformity and constant strain rate in SHPB test[J]. Explosion and Shock Waves, 2005, 25(3): 207-216. doi: 10.3321/j.issn:1001-1455.2005.03.003 -
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