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This paper studies the mechanical properties of the aramid fiber reinforced epoxy resin composite by varying the percentage composition. Three different compositions of aramid fiber are 30 %, 35 % and 45 % by weight. The aramid epoxy composite was manufactured by the vacuum suction method. The manufactured composites are then cured by the hot air oven for 180 minutes. The prepared composites undergo through various tests such as the tensile test, hardness test and impact test. The results of the tests on the three compositions analyzed and variation in its mechanical properties is noted.

This study investigates the resulting nanocomposite material formed by hot-forming and molding epoxy resin containing diluent, nanosilica powder, and hardener. The effects of different processing conditions on the composite material, such as post-processing, nanopowder content, thinner amount, etc. The optimal processing conditions can be discovered by analyzing samples with a differential scanning calorimeter (DSC) to discern the glass transition temperature (Tg). Experimental results show that without post-processing, the composite material would not have enough reaction time, and that without thinner, the sample containing 1 wt% nanopowder had the highest Tg. The addition of thinner lowers the Tg of a sample, leading to reduced thermal properties.

In order to increase the sensitivity, frequency bandwidth and longitudinal resolution of the 1-3 cement-based piezoelectric ultrasonic sensor, different metal powder/epoxy resin composite materials were used to make backing layer, and the performances of sensors were evaluated and compared. The results indicated that the increase of the sensitivity and the frequency bandwidth, as well as a decrease of the pulse wave number can be observed when the backing materials of metal powder/epoxy resin composite materials were added to the sensor. A 42%-increase of the maximum peak-to-peak value of the echo pulse response, a 52%-reduction of the ring down time and a 200%-increase of the bandwidth can be achieved by using the backing material.

Multi-walled carbon nano-tubes and carbon fiber reinforced epoxy resin (MWCNTs/CF/EP) composite patch was prepared by the route of hot-melt impregnation. The results of the mechanical properties shown that adding MWCNTs had made the tensile strength and interlaminar shear strength increased by 9.79% and 3.1%, separatively. It was detected using the ultrasonic non-destructive technique that the composite patch had a good interlaminar combination with no defects as obvious resin enrichment or insufficient gel content except for some slight stratification phenomenon in few parts. The high heat-resistance obtained by TG.

0-3 PMN/EP composites were prepared with different PMN particle size of powder A(100~154μm), B(74~100μm), C(66~74μm), D(45~66μm) , E(7~35μm) and F(0.15~18μm) by resin casting method. Particle size has great effect on property of PMN/EP composite. SEM analysis indicates that PMN particles with small size dispersed more uniformly in epoxy resin. The dielectric constant and dielectric loss of 0.1PMN/0.9EP and 0.3PMN/0.7EP composites vary a little with the particle size increasing, but dielectric constant and dielectric loss of 0.4PMN/0.6EP increase rapidly. Dielectric frequency characteristics analysis suggest that the variation trend of dielectric constant with different particle size at frequency of 103～106 Hz are almost similar in 0.3 PMN/0.7EP composites, but the dielectric constant of 0.4PMN/0.6EP composite with larger particle size drops remarkably with the frequency increase.