摘要
增材制造技术能够制造复杂点阵结构。相比于传统的加工工艺,可以一次成型,克服了低速冲击下传统工艺芯层与面层在连接点处易发生脱粘的问题。利用低速落锤试验装置对增材制造面心立方(FCC)夹芯板和体心立方(BCC)夹芯板进行了低速冲击试验,获得了两种微桁架点阵夹芯板的破坏模式和冲击响应曲线。低速冲击下,微桁架夹芯板上面层在冲击部位产生局部凹坑,并出现裂纹,其余部位没有大变形。试验结果表明在相同能量冲击下,BCC夹芯板的凹坑深度要小于FCC夹芯板,BCC夹芯板的抗冲击性能要优于FCC夹芯板;建立有限元模型,较好地表征了低速冲击过程中微桁架结构的损伤。发现在低速冲击过程中,对于两种微桁架点阵夹芯板,冲击能量主要由上面层和芯层吸收;冲击能量改变,夹芯板各部分吸能百分比变化较小。BCC夹芯板和FCC夹芯板结构稳定,整体性好;低速冲击下,FCC夹芯板最先发生破坏的部位是上面层与芯层连接处;而BCC夹芯板最先发生破坏的部位是中间竖直桁架。
Additive manufacturing technology is capable of molding complex lattice structures at one time,overcoming the debond problem at the connection point of the core layer and the surface layer of the traditional technology under low-velocity impact.Low-velocity impact tests were performed on additively manufactured Face-Centered Cube(FCC)sandwich panels and Body-Centered Cube(BCC)sandwich panels respectively,using a drop-weight test device,from which the failure mode and impact curves of the sandwich panels were obtained.The smaller indentation depth on BCC sandwich panels than that on FCC sandwich panels under the same energy impact indicates better impact resistance of BCC than FCC sandwich panels.Under low-velocity impact,apit and a crack appeared at the impact site on the upper layer of the lattice sandwich.However,no large deformation occurred in the rest of the area.A finite element model was developed to simulate the impact response of lattice sandwich panels.For both panels,the impact energy is mainly absorbed by the upper layer and the sandwich layer,with the energy absorption ratio of each part changing little when the impact energy changes.Thus the overall structure of both BCC and FCC sandwich panels is stable and integral.The damage of the FCC sandwich panel initiates from the connection between the upper layer and the vertical truss,while that of the BCC sandwich panel initiates from the vertical truss.
作者
郭怡东
马玉娥
李佩谣
GUO Yidong;MA Yu'e;LI Peiyao(School of Aeronautics,Northwestern Polytechnical University,Xi'an 710072,China)
出处
《航空学报》
EI
CAS
CSCD
北大核心
2021年第2期370-380,共11页
Acta Aeronautica et Astronautica Sinica
基金
国家自然科学基金(91860128)
陕西省创新能力支撑项目(2018KW-028)。
关键词
增材制造
钛合金
低速冲击
FCC和BCC微桁架结构
破坏模式
additive manufacture
titanium alloy
low-velocity impact
FCC and BCC lattice structures
failure mode
