Study On The Basalt Fiber Critical Length And The Performance Of Basalt Fiber Reinforcing Wood-plastic Composite Material

With the dwindling of the forest resources，wood-plastic composites (WPC)which is made of wood and plastic by a certain new molding process has beendeveloping rapidly in recent years. Because of the high performance and cheap price,WPC is favored by people, but it also has many disadvantages, for example: theaccelerated aging of WPC, the color fading of the material, the weak mechanicalbehavior of material, immersion warping and so on.The performance and price of basalt fiber (BF) is between the glass fiber andcarbon fiber. In addition to its high strength and high modulus, it also has many otherhigh performances, for instance: the high temperature resistance, the oxidationresistance, the noise insulation, the high shear strength and the characteristics ofadapting to a variety of environmental condition. Because of its high costperformance, its application has been promoted rapidly.In the external force action, fiber reinforced composites transfers the stressuniformly to the fiber and matrix by the interface. However, the interface of the fiberreinforced composite can transfer the stress effectively depending on the degree of thebinding interface between fiber and matrix.Single fiber pull-out experiment is one ofthe common methods of determining the interfacial properties of fiber reinforcedcomposites, which is able to reflect the combination property of the interface visuallyand quantitatively.The main contents and conclusion of this paper are as follows:1) According to the theory of the stress transfer in fiber composites, the paperputs forward the fiber critical length. Through analyzing the force of the fibers in thecomposite, the maximum tensile stress of the fibers appears in the middle of fiber, sothat the fiber breakage occurs in the middle section.2) Through finite element analysis with ANSYS, the single fiber pull-out processis simulated using the parametric design language (APDL) and the ANSYS elementbirth and death technology, and the critical length of the embedded fiber is3.8mm.3) This paper designs a method of the sample pretreatment for single fiberpull-out test and analyzes the SEM images of embedded fibers. The results show thatthe embedded length of the single fiber is3.0mm. 4) According to the finite element simulation and experimental results of singlefiber pull-out test, the paper designs five different embedded length of fiberreinforced plastic composite materials, and tests the reinforcing effect of choppedfiber mat from the macro. The results show that the critical length of fiber is between5mm and8mm.