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Development of composite materials has increased rapidly in different fields of sciences. This offers new structures of reinforcement materials and risen. More recently, the use of nanomaterials as reinforcement materials has proliferated. This research studies the mechanical properties and electrical characteristics of hybrid composite materials. Glass reinforced epoxy (GRE) was used as a basic composite in addition to the nanomaterial which was mixed with the risen using different percentages. Multi-wall carbon nanotubes (MWCNT) and Silica (Silicon Dioxide SiO2) were used as nano-particles. The ratios of nano-particles used to reinforce the Epoxy were (0.1, 0.2, and 0.5%) of weight ratio for MWCNT and (1, 2, and 5%) of weight ratio for Silica nanoparticles (SiO2). The results showed that the ultimate strength for GRE with 0.1 wt%MWCNT-1 wt%SiO2 was the highest, while Young’ modulus for GRE with 0.2 wt%MWCNT-2 wt%SiO2 was the highest. In addition, the samples with 0.1 wt%MWCNT-1 wt%SiO2 showed a magnificent value of electric conductivity. Having finished the mechanical tests, the fracture surfaces were comparatively examined using scanning electron microscopy (SEM).

In this study, the influences of eggshell powder application on random fiberglass/polyester composite pipes thermal stresses were investigated experimentally and numerically. The experimental part involved industrializing tube samples which are Egg Shell Powder with Polyester at 50% volume fraction.(E50), Random Fiberglass with plyester at 50% volume fraction (F50) and Egg Shell Powder with Random Fiberglass with Polyester at 50% volume fraction (E25F25). Resin molding procedure and experimental rig design to study how tube samples are faced with thermal loads. Pipes are made with (95 mm) inner diameter, (400 mm) circumference, and (5 mm) wall thicknesses. Computational Fluid Dynamic, ANSYS software package version 11, is simulated with product form SHELL63. Results show that, composite samples (F50) had an average longitudinal strain, while composite samples (E50) had a low longitudinal strain. The composite (F50) had average longitudinal and hoop stress (62.2 MPa, and 61.1 MPa) respectively, while the composite (E50) had low longitudinal hoop stress (28.5 MPa, ad 30.8 MPa) respectively.

This study focused on the electrical and thermal properties of many natural composite material specimens. In this study, three kinds of composite materials were used epoxy, jute, and fibreglass. The first type was epoxy-strengthened glass fibre with volume fraction (50%), the second type of Hybrid natural jute, and glass fibre strengthened epoxy of (50%) thickness proportion (25%glass fibre + 25 %jute). Finally, the third type of natural fibre (jute) was strengthened with a volume fraction of epoxy (50%). This research was studied the thermal and electrical conductivity for three types of composite. Results revealed that the values of thermal conductivity and electrical conductivity for fibreglass/epoxy composite samples outweigh two other forms.

Friction stir spot welding (FSSW) method was performed for welding of aluminum alloys AA6061-T6 with pure aluminum AA1100 sheets having thicknesses of 2.4 and 3 mm respectively. FSSW procedure was accomplished at varied tool rotational speeds (1000, 1600, and 2000 rpm). The dwell time was (2, 4, and 6 sec) and the geometry of the tool pin was threaded cylindrical pin with a cylindrical and straight shoulder. The aluminum alloy AA6061-T6 sheet was overlapped on the pure aluminum AA1100 sheet. The tensile shear test was investigated for all specimens. It was deduced that the value of the maximum shear force is 1.95 kN. This value was obtained at the following welding factors: 2000 rpm spindle rotational speed, 4 sec dwell time and threaded cylindrical pin profile, the two other factors which were pin length and plunging time were kept as constant parameters through the tests at 3.2 mm and 40 sec respectively. It was also concluded that the fracture happens in the nugget zone mode at the highest lap-shear load.

The mechanical, thermal and electrical properties of wool and glass fiber-reinforced epoxy-based hybrid composites were investigated experimentally. Three different types of the composite material were manufactured. The first type was plain woven glass fiber reinforced epoxy with 50% volume fraction. The second type consisted of natural fiber (Wool) reinforced epoxy with 50% volume fraction. The third type was hybrid natural wool and plain woven glass fiber reinforced epoxy with 50% volume fraction (25% fiber + 25% wool). The results showed that the hybrid composite specimens have higher values of the tensile strength, modulus of elasticity and flexural strength compared with the wool specimens, while these values are less than that for glass fiber specimens. The values of the thermal conductivity and electrical conductivity are arranged in an ascending order as follows: wool/epoxy, wool-glass/epoxy, and glass/epoxy composites.

The behavior of wear for composite materials with effect of hygrothermal was investigated experimentally. The pin-on-disc wear rig was manufacturing. The wear parameters, distance, humidity, applied load, temperature, and speed on the wear behavior was investigated. These composite materials consist of (fiberglass and polyester resin), with (40%) volume fraction. The results give the increasing of humidity and, or temperature causes increasing in glass-fiber/polyester composite’s wear. Also, increasing the load, distance and sliding speed, will be led to an increase in the wear of glass fiber/polyester.

This work is an experimental and numerical approach to analyze the effect of Nano powder additives and temperature on the critical crack length in fiber reinforced composite materials (FRC) exposed to uniaxial tensile load. Fiberglass/Epoxy compact tension test samples (CT) are prepared according to ASTM standard E399 . Tio2 Nano powder is added by 2% wt to the resin to other samples. The static tensile test is applied to the samples and the results for crack length/time are discussed. ABAQUS/CAE software is used to simulate the case. The numerical and experimental results were close. The experimental results showed that the addition of 2%wt Tio2 Nano powder increased the critical crack length by 32.4%. The effect of ambient temperature is studied too by applying the experimental test on the fiberglass/Epoxy samples in room temperature (30°C) once and at outdoor (60°C) temperature. The results showed that the effect of the temperature increase decreased the critical crack length by 51%. The numerical results determined the fracture toughness (KIC) for the fiberglass/Epoxy samples to be 491 pa.mm0.5 and 517 pa.mm0.5 for the fiberglass/Epoxy-Nano powder samples.