Fabrication and mechanical performance of K-cor reinforced foam sandwich structure

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-cor 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.