球形孔开孔泡沫铝的力学特性及准静态压缩变形机制
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摘要
对胞孔形态和尺寸较为一致的球形孔泡沫铝开展静-动态压缩实验,利用数字图像相关法研究了泡沫铝在准静态压缩过程中的宏观和介观变形机理。结果表明:球形孔泡沫具有明显的应变率效应,随着应变率的增加,平台应力及屈服强度增加,吸能效率也有所提高。由于胞元壁厚不均匀和孔壁缺陷的随机分布,泡沫铝在压缩过程中会出现多条局部变形带,单个胞孔表面在孔壁缺陷处也会出现应变集中带。胞元孔的变形模式主要有3种,轴向压缩、剪切、扭转加剪切复合变形,且整体变形带处的孔壁破坏模式以剪切变形为主,孔壁的变形模式又与孔壁自身厚度以及加载方向有关。
In this work we investigated the quasi-static and dynamic compression of spherical cell aluminum foam with homogeneous pore morphology and size. We identified the deformation mechanisms of the aluminum foam in the quasi-static compression at both macroscopic and mesoscopic levels using digital image correlation. The results showed that the compressive strength, plateau stress and energy absorption were significantly improved by increasing the loading strain rate, that is, the spherical cell aluminum foam exhibited obvious strain rate sensitivity. Because of the inhomogeneous cell wall thickness and the random distribution of cell wall defects, the deformation bands dominated the compressive behavior during the compression process, and the strain concentration zones were observed on the single cell hole where the cell wall defects were identified. Meanwhile we examined the implications of compressive behaviors operating on the mesoscopic cell walls and the formation of macroscopic deformation bands. The deformation modes of cells mainly fell into 3 types, i.e. axial compression, shear, torsion and shear combined deformation. The failure mode of the cell walls throughout the deformation zone was mostly determined by shear deformation,which was obviously related with the cell wall thickness and the loading direction.
In this work we investigated the quasi-static and dynamic compression of spherical cell aluminum foam with homogeneous pore morphology and size. We identified the deformation mechanisms of the aluminum foam in the quasi-static compression at both macroscopic and mesoscopic levels using digital image correlation. The results showed that the compressive strength, plateau stress and energy absorption were significantly improved by increasing the loading strain rate, that is, the spherical cell aluminum foam exhibited obvious strain rate sensitivity. Because of the inhomogeneous cell wall thickness and the random distribution of cell wall defects, the deformation bands dominated the compressive behavior during the compression process, and the strain concentration zones were observed on the single cell hole where the cell wall defects were identified. Meanwhile we examined the implications of compressive behaviors operating on the mesoscopic cell walls and the formation of macroscopic deformation bands. The deformation modes of cells mainly fell into 3 types, i.e. axial compression, shear, torsion and shear combined deformation. The failure mode of the cell walls throughout the deformation zone was mostly determined by shear deformation,which was obviously related with the cell wall thickness and the loading direction.
引文
[1]王展光,褚旭明,何德坪,等.强度、吸能与韧性兼容的新型球形孔泡沫纯铝[J].东南大学学报(自然科学版),2007,37(6):985-989.WANG Z G,CHU X M,HE D P,et al.New type of spherical of pores Al foam possessing strength,energy absorption and toughness[J].Journal of Southeast University(Natural Science Edition),2007,37(6):985-989.
[2]王怀文,亢一澜,谢和平.数字散斑相关方法与应用研究进展[J].力学进展,2005,35(2):195-203.WANG H W,KANG Y L,XIE H P.Advance in digital speckle correlation method and its application[J].Advances in Mechanics,2005,35(2):195-203.
[3]陈忠,陈教豆.基于双目立体视觉与数字散斑图像相关的全场振动测量[J].振动与冲击,2015(13):121-126.CHEN Z,CHEN J D.Full-field vibration measurement based on binocular stereo vision and digital speckle image correlation[J].Journal of Vibration and Shock,2015(13):121-126.
[4]魏志强,黄小清,杨宝,等.应用高速摄影机对泡沫铝在SHPB实验过程的变形跟踪与分析[J].实验力学,2011,26(2):117-123.WEI Z Q,HUANG X Q,YANG B,et al.Tracking of aluminum foam deformation in SHPB experiment by using high-speed camera[J].Journal of Experimental Mechanics,2011,26(2):117-123.
[5]JUNG A,WOCKER M,CHEN Z,et al.Micro tensile testing of open-cell metal foams-experimental setup,micromechanical properties[J].Materials&Design,2015,88:1021-1030.
[6]房亮,唐兆琛,杨福俊,等.数字图像相关方法在闭孔泡沫铝压缩试验中的应用[J].实验力学,2008,23(2):162-168.FANG L,TANG Z C,YANG F J,et al.Compressive test of closed-cell aluminum foam based on digital image correlation method[J].Journal of Experimental Mechanics,2008,23(2):162-168.
[7]章超,徐松林,王鹏飞.基于数字图像相关方法对冲击载荷下泡沫铝全场变形过程的测试[J].实验力学,2013,28(5):629-634.ZHANG C,XU S L,WANG P F.Test of aluminum foam deforming process under impact load based on digital image load based on digital image correlation method[J].Journal of Experimental Mechanics,2013,28(5):629-634.
[8]KADKHODAPOUR J,RAEISI S.Micro-macro investigation of deformation and failure in closed-cell aluminum foams[J].Computational Materials Science,2014,83(2):137-148.
[9]杨福俊,唐兆琛,朱莉,等.闭孔泡沫铝特征统计及其变形行为实验研究[J].东南大学学报(自然科学版),2009,39(2):250-254.YANG F J,TANG Z C,ZHU L,et al.Experimental study on cellular structure statistical analysis and uniaxial deformation behavior of closed-cell aluminum foam[J].Journal of Southeast University(Natural Science Edition),2009,39(2):250-254.
[10]李忠献,张茂轩,师燕超.闭孔泡沫铝的动态压缩性能试验研究[J].振动与冲击,2017,36(5):1-6.LI Z X,ZHANG M X,SHI Y C.Tests for dynamic compressive performance of closed-cell aluminum foams[J].Journal of Vibration and Shock,2017,36(5):1-6.
[11]章超.数字图像相关方法在动态测试中的应用[D].合肥:中国科学技术大学,2014:41-58.ZHANG C.Application of digital imaging correlation in dynamic testing[D].Hefei:University of Science and Technology of China,2014:41-58.
[12]朱烨飞,孙雨果.单轴压缩载荷下闭孔泡沫铝的变形机制[J].复合材料学报,2017,34(8):1810-1816.ZHU Y F,SUN Y G.Deformation mechanism of closed-cell aluminum foam under uni axial compression[J].Acta Materiae Compositae Sinica,2017,34(8):1810-1816.
[13]潘艺,胡时胜,蒋家桥,等.泡沫铝泡孔动态变形特性研究[J].爆炸与冲击,2004,24(5):407-412.PAN Y,HU S S,JING J Q,et al.Dynamic deform ability of cell in aluminum foams[J].Explosion and Shock Waves,2004,24(5):407-412.
[14]MU Y,YAO G,LIANG L,et al.Deformation mechanisms of closed-cell aluminum foam in compression[J].Scripta Materialia,2010,63(6):629-632.
[15]杨宝,汤立群,刘逸平,等.冲击条件下泡沫铝的细观变形特征分析[J].爆炸与冲击,2012,32(4):399-403.YANG B,TANG L Q,LIU Y P,et al.Meso deformation characteristics analysis of aluminum foam under impact[J].Explosion and Shock Waves,2012,32(4):399-403.
[16]陈永涛,楼志华,郑钢铁.开孔和闭孔泡沫铝的力学与吸能特性研究[J].高能量密度物理,2006(2):47-49.CHEN Y T,LOU Z H,ZHENG G T.Study on mechanics and energy absorption characteristics of open and closed cellular aluminum foam[J].High Energy Density Physics,2006(2):47-49.
[17]DESHPANDE V S,FLECK N A.High strain rate compressive behavior of aluminum alloy foams[J].International Journal of Impact Engineering,2000,24(3):277-298.
[18]MUKAI T,KANAHASHI H,MIYOSHI T,et al.Experimental study of energy absorption in a close-celled aluminum foam under dynamic loading[J].Scripta Materialia,1999,40(8):921-927.
[19]程和法,黄笑梅,许玲.泡沫铝的动态压缩性能和吸能性研究[J].兵器材料科学与工程,2003,26(5):37-43.CHENG H F,HUANG X M,XU L.Influence of TIG dressing on micro structure and fracture toughness of welding joint[J].Ordnance Material Science and Engineering,2003,26(5):37-43.
[20]王志华.泡沫铝合金动态力学性能及其吸能机理的研究[D].太原:太原理工大学,2005:41-42.WANG Z H.Studies on the dynamic mechanical properties and energy absorption of aIum1num alloy foams[D].Taiyuan:Taiyuan University of Technology,2005:41-42.
[21]WANG P,XU S,LI Z,et al.Experimental investigation on the strain-rate effect and inertia effect of closed-cell aluminum foam subjected to dynamic loading[J].Materials Science&Engineering A,2015,620:253-261.
[2]王怀文,亢一澜,谢和平.数字散斑相关方法与应用研究进展[J].力学进展,2005,35(2):195-203.WANG H W,KANG Y L,XIE H P.Advance in digital speckle correlation method and its application[J].Advances in Mechanics,2005,35(2):195-203.
[3]陈忠,陈教豆.基于双目立体视觉与数字散斑图像相关的全场振动测量[J].振动与冲击,2015(13):121-126.CHEN Z,CHEN J D.Full-field vibration measurement based on binocular stereo vision and digital speckle image correlation[J].Journal of Vibration and Shock,2015(13):121-126.
[4]魏志强,黄小清,杨宝,等.应用高速摄影机对泡沫铝在SHPB实验过程的变形跟踪与分析[J].实验力学,2011,26(2):117-123.WEI Z Q,HUANG X Q,YANG B,et al.Tracking of aluminum foam deformation in SHPB experiment by using high-speed camera[J].Journal of Experimental Mechanics,2011,26(2):117-123.
[5]JUNG A,WOCKER M,CHEN Z,et al.Micro tensile testing of open-cell metal foams-experimental setup,micromechanical properties[J].Materials&Design,2015,88:1021-1030.
[6]房亮,唐兆琛,杨福俊,等.数字图像相关方法在闭孔泡沫铝压缩试验中的应用[J].实验力学,2008,23(2):162-168.FANG L,TANG Z C,YANG F J,et al.Compressive test of closed-cell aluminum foam based on digital image correlation method[J].Journal of Experimental Mechanics,2008,23(2):162-168.
[7]章超,徐松林,王鹏飞.基于数字图像相关方法对冲击载荷下泡沫铝全场变形过程的测试[J].实验力学,2013,28(5):629-634.ZHANG C,XU S L,WANG P F.Test of aluminum foam deforming process under impact load based on digital image load based on digital image correlation method[J].Journal of Experimental Mechanics,2013,28(5):629-634.
[8]KADKHODAPOUR J,RAEISI S.Micro-macro investigation of deformation and failure in closed-cell aluminum foams[J].Computational Materials Science,2014,83(2):137-148.
[9]杨福俊,唐兆琛,朱莉,等.闭孔泡沫铝特征统计及其变形行为实验研究[J].东南大学学报(自然科学版),2009,39(2):250-254.YANG F J,TANG Z C,ZHU L,et al.Experimental study on cellular structure statistical analysis and uniaxial deformation behavior of closed-cell aluminum foam[J].Journal of Southeast University(Natural Science Edition),2009,39(2):250-254.
[10]李忠献,张茂轩,师燕超.闭孔泡沫铝的动态压缩性能试验研究[J].振动与冲击,2017,36(5):1-6.LI Z X,ZHANG M X,SHI Y C.Tests for dynamic compressive performance of closed-cell aluminum foams[J].Journal of Vibration and Shock,2017,36(5):1-6.
[11]章超.数字图像相关方法在动态测试中的应用[D].合肥:中国科学技术大学,2014:41-58.ZHANG C.Application of digital imaging correlation in dynamic testing[D].Hefei:University of Science and Technology of China,2014:41-58.
[12]朱烨飞,孙雨果.单轴压缩载荷下闭孔泡沫铝的变形机制[J].复合材料学报,2017,34(8):1810-1816.ZHU Y F,SUN Y G.Deformation mechanism of closed-cell aluminum foam under uni axial compression[J].Acta Materiae Compositae Sinica,2017,34(8):1810-1816.
[13]潘艺,胡时胜,蒋家桥,等.泡沫铝泡孔动态变形特性研究[J].爆炸与冲击,2004,24(5):407-412.PAN Y,HU S S,JING J Q,et al.Dynamic deform ability of cell in aluminum foams[J].Explosion and Shock Waves,2004,24(5):407-412.
[14]MU Y,YAO G,LIANG L,et al.Deformation mechanisms of closed-cell aluminum foam in compression[J].Scripta Materialia,2010,63(6):629-632.
[15]杨宝,汤立群,刘逸平,等.冲击条件下泡沫铝的细观变形特征分析[J].爆炸与冲击,2012,32(4):399-403.YANG B,TANG L Q,LIU Y P,et al.Meso deformation characteristics analysis of aluminum foam under impact[J].Explosion and Shock Waves,2012,32(4):399-403.
[16]陈永涛,楼志华,郑钢铁.开孔和闭孔泡沫铝的力学与吸能特性研究[J].高能量密度物理,2006(2):47-49.CHEN Y T,LOU Z H,ZHENG G T.Study on mechanics and energy absorption characteristics of open and closed cellular aluminum foam[J].High Energy Density Physics,2006(2):47-49.
[17]DESHPANDE V S,FLECK N A.High strain rate compressive behavior of aluminum alloy foams[J].International Journal of Impact Engineering,2000,24(3):277-298.
[18]MUKAI T,KANAHASHI H,MIYOSHI T,et al.Experimental study of energy absorption in a close-celled aluminum foam under dynamic loading[J].Scripta Materialia,1999,40(8):921-927.
[19]程和法,黄笑梅,许玲.泡沫铝的动态压缩性能和吸能性研究[J].兵器材料科学与工程,2003,26(5):37-43.CHENG H F,HUANG X M,XU L.Influence of TIG dressing on micro structure and fracture toughness of welding joint[J].Ordnance Material Science and Engineering,2003,26(5):37-43.
[20]王志华.泡沫铝合金动态力学性能及其吸能机理的研究[D].太原:太原理工大学,2005:41-42.WANG Z H.Studies on the dynamic mechanical properties and energy absorption of aIum1num alloy foams[D].Taiyuan:Taiyuan University of Technology,2005:41-42.
[21]WANG P,XU S,LI Z,et al.Experimental investigation on the strain-rate effect and inertia effect of closed-cell aluminum foam subjected to dynamic loading[J].Materials Science&Engineering A,2015,620:253-261.