K-cor增强泡沫夹层结构制备与力学性能

摘要

选取NHZP-1型双马树脂拉挤Z—pin，并结合差示扫描量热法（DSC）测定及工艺参数优化来调控其固化度，将Z—pin按70°角（Z—pin植入方向与水平方向夹角）植入Rohacell-51WF泡沫、采用5429／HT7双马单向预浸料作为蒙皮，成功制备K-cor夹层结构，并展开了相应的力学性能测试。根据Z-pin在K-cor与X-cor夹层中与蒙皮结合方式差异建立微观拉伸结构简图，并借助欧拉杆屈曲模型来估算其临界失稳载荷，定性分析了平面压缩过程中Z-pin的破坏模式与增强机制。结果表明：Z-pin固化度为62．74％时，K-cor夹层结构的平面拉伸强度和模量分别为1．55MPa与88．56MPa，平面压缩强度和模量高达3．61MPa与128．84MPa，均比空白泡沫试样和具有相同Z-pin参数的X-cor夹层结构有所提高。%K-cor structure was successfully fabricated by inserting angle 70° Z-pin in Rohacell- 51WF foam, using NHZP- 1 and 5429/HT7 bismaleimides as pultrusion resin and preimpregnated medium, respectively. The corresponding investigation on mechanical tests were carried out. A structural model based on different binding styles between Z-pin and panel in K-and X-cot was established. In order to qualitatively describe the failure mode and strengthening mechanism, the critical stress of Z- pin in the compressive test was evaluated and compared by using Euler column buckling modes. The experimental results show that 62.74 % curing degree of Z-pin in K-cor structure can make tensile strength and modulus reach 1.55 MPa and 88.56 MPa as well as 3.61 MPa and 128.84 MPa, respectively, in the compressive test, which is much higher than that of X-cor structure and blank foam matrix.