Study On Preparation And Property Of Fiber Reinforced Lightweight Compression-resistance Composites

Buoyancy material is a very important part of the ocean detecting instrument which include bathyscaphe and Remote Operated Vehicle and so on.The comprehensive property of buoyancy material has gone better as the development of the ocean exploration.The solid buoyancy material composed of hollow microsphere and epoxy resin is the research focus of the buoyancy material.In this paper,a composite constituted of chopped carbon fiber,hollow glass microsphere and epoxy resin was prepared by molding process.The density,compressive strength,saturated water absorption,strength retention of the composite is 0.60g/cm~3-0.70g/cm~3,65.11MPa-68.87MPa,0.63%-0.81%,97.1%-98.3%,respectively.The optimal cure schedule 50℃/2h+100℃/2h+140℃/2h was confirmed by DSC curve analysis.The mechanical property,viscosity,glass-transition temperature(T_g)was studied.The results showed that when the diluent content is 5wt%the epoxy resin gain the optimal compressive property.The tensile strength,flexural strength,compressive strength,T_g is 46.10MPa、125.51MPa、99.65MPa、104℃,respectively.The influence of surface treatment,types and volume fractions of hollow glass microsphere on the composites was studied.The study showed that,the surface treatment promoted the wettability of hollow microsphere in the epoxy resin,which improve the compressive strength of the composites.The K46 composites show the maximum compressive strength compared to the other type of composites at the same density.The density of the composites decreased as the hollow microsphere volume fractions increased.The actual and theoretical density had a large difference when the K25、K46 volume fractions exceeded 70%、75%,respectively.The K1 hollow microsphere is too weak to bear with pressure from the mixing machine,the actual density of K1 composites is higher than theoretical density.The volume fraction of hollow microsphere also have an influence on the compressive strength,when the volume fraction increase from 60%to 80%,the compressive strength of K1,K25,K46 composites decrease from 24.64MPa、52.40MPa、64.32MPa to 14.68MPa、30.80MPa、45.93MPa.In this paper,chopped carbon fiber reinforced K46/resin epoxy composites was prepared.The density,compression strength,water absorption rate of the composite were studied,when the K46 volume fraction is 70%、75%、80%,respectively.The results showed that when the carbon fiber percentage increased,the compressive strength increased and the saturated water absorption decreased.When the carbon fiber percentage is 4%,the compressive strength of composite with 70vol%,75vol%,80vol%hollow glass microsphere included were 68.87MPa,65.11MPa,57.24MPa,respectively.The minimum saturated water absorption of the composite with 70vol%glass microsphere is 0.63%when the carbon fiber percentage is 2%.When the carbon fiber content was 4%,the composite with 75vol%,80vol%glass microsphere included showed the minimum saturated water absorption rate of 0.81%and 1.15%,respectively.Also,the strength retention rate is affected by carbon fiber percentage.When the carbon fiber percentage is 4%,the composites show the maximum strength retention rate,which is 98.3%、97.1%、94.5%,respectively.