Mechanical Research On Basalt Fiber Reinforced Unsaturated Polyester Composite

Fiber-reinforced polymer composites are excellent lightweight materials.They have high specific strength,excellent corrosion resistance,and ideal economic efficiency.Therefore,they are widely used in automobiles,ships,medical,defense and aviation Aerospace and other fields.However,when subjected to structural loads,due to their inherent brittleness and delamination sensitivity,they are prone to delamination failure and lose their bearing capacity.Therefore,the development of lightweight composites with high strength and high toughness is one of the most important tasks in the field of composite materials.Unsaturated polyester(UP)is widely used to develop high-performance lightweight fiber-reinforced composites due to its excellent mechanical properties and lightweight properties.Basalt fiber(BF)is a natural mineral fiber which is made of volcanic rock material.It is called a pollution-free"green industrial raw material"in the 21st century.It has high strength and high elastic modulus.In the paper,BF is used as the reinforcement and 196 UP is used as the matrix to fabricate the BF/UP composites.The composites are toughened by silica carbon black(SiCB)and short basalt fiber(SBF)to improve their strength and toughness.The main research contents and conclusions are as follows:(1)The BF/UP composites toughened by SiCB were fabricated by compression molding.With the increase of SiCB content,the mechanical properties of composites increase first and then decrease.When the SiCB content is 1.5 wt%,the tensile strength,elongation at break,flexural strength,energy absorption,impact strength and mode II interlaminar fracture toughness of composites increase by 15%,9%,105%,79%,27%and 156%.(2)Surface treatment of SiCB with silane coupling agent KH-550 to obtain modified silicon carbon black(m SiCB).Using m SiCB to toughen BF/UP composites can enhance the mechanical properties of composites.When the content of m SiCB is 1.5 wt%,the tensile strength,elongation at break,flexural strength,energy absorption,impact strength and mode II interlaminar fracture toughness of m SiCB/BF/UP composites reach the maximum.Compared with the BF/UP composites,the maximum increases are 19%,11%,138%,120%,39%and 216%.Compared with the SiCB/BF/UP composites,the maximum increases are 9%,3%,30%,55%,16%and 47%.(3)SBF/BF/UP composites with SBF lengths of 3,6,9,12 mm and surface densities of10,20,30,and 40 g/m~2 were fabricated by compression molding.The effect of the length and surface density of SBF on the mechanical properties of SBF/BF/UP composites was researched.The results show that SBF can improve the mechanical properties of composites.In various combinations,when the SBF length is 6 mm and the surface density is 30 g/m~2,the mechanical properties of the composites reach the best.Its best tensile strength,elongation at break,flexural strength,energy absorption and mode II interlaminar fracture toughness increase by 27%,50%,101%,58%,19% and 103% respectively.