The present study is an attempt to fabricate composite nanofiber mats from polystyrene (PS) loaded with exfoliated graphite nanosheets (EGNS) by using electrospinning technique. EGNS with different weight ratios of 3, 6, and 9 wt.% were added to PS (20 wt.%). The fiber diameter and morphology of the composite nanofiber mats were investigated by scanning electron microscopy (SEM). Results revealed that as EGNS concentration was increased, the average diameter of EGNS/PS electrospun nanofibers decreased. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were used to investigate the thermal properties. The tensile strengths and Young’s modulus of the composites improve with the increasing EGNS concentrations compared to PS nanofiber, which indicates 84% and 88% augmentation, respectively at 6 wt.% of EGNS. Also, the addition of EGNS increased thermal stability of composite nanofiber mats.

This work is an attempt to fabricate aluminum (AA 5049) matrix composites (AMCs) reinforced with electrospun polyacrylonitrile (PAN) nanofibers and consisting of exfoliated graphite nanosheets (EGNS/PAN) by utilizing friction stir processing (FSP) to improve the mechanical characteristics of AA 5049. PAN and EGNS/PAN nanofibers were fabricated using the electrospinning technique. The average diameter of the electrospun PAN nanofibers is 195 ± 57 nm, and after EGNS incorporation is 180 ± 68nm. The incorporation of nanofiber reinforcement can enhance the mechanical characteristics of AA5049. The mechanical characteristics of AA5049 can be enhanced by the procedure of incorporating nanofibers, making them an ideal choice for applications in the automotive and aerospace industries. PAN and EGNS/PAN nanofiber reinforcement enhanced the hardness to 89 and 98 Hv, respectively. Also, the ultimate tensile strength was raised to 291 MPa and 344 MPa, respectively.

In this work, friction stir processing (FSP) was used to successfully embed boron carbide (B4C) particles into an aluminum matrix (AA6061-T6). Four specimens of aluminum 6061 composite reinforced with 4%, 6%, 8%, and 10% volume fraction of B4C were manufactured. The effects of B4C particles volume fraction on microstructure, mechanical and wear properties are investigated. The microstructural investigations demonstrated that a rise in the volume % of reinforcement greatly decreased the matrix grain size. The manufactured AA6061-T6 loaded with B4C surface composites demonstrated homogeneous B4C particle dispersion, with no significant particle clustering in the stir zone. In addition, it was established that increasing the volume fraction of B4C particles promoted grain refinement, increased hardness, and tensile strength. X-ray diffraction (XRD) was used to identify the reinforcement dispersion. For AA6061-T6 with 10% B4C particles, a maximum hardness value of 163 HV was obtained in the stir zone. Maximum yield strength of 165 MPa and ultimate tensile strength of 220 MPa were attained by AA6061-T6 with 10% B4C particles, which is an improvement of 21% over the specimen FSP without reinforcement. The strengthening of the grain refining was attributed for the increase in hardness and strength. The ductility was reduced by the incorporation of more B4C particles. Comparing the surface composite loaded with B4C to unreinforced friction stir processing and AA6061-T6 as received, it demonstrated superior wear resistance.

This work is an attempt to fabricate aluminum (AA 5049) matrix composites (AMCs) reinforced with electrospun polyacrylonitrile (PAN) nanofibers and consisting of exfoliated graphite nanosheets (EGNS/PAN) by utilizing friction stir processing (FSP) to improve the mechanical characteristics of AA 5049. The electrospinning method was used for fabricating PAN and EGNS/PAN nanofibers. The average diameter of the electrospun PAN nanofibers is 195 ± 57 nm, and after EGNS incorporation is 180 ± 68 nm. Dynamic recrystallization was the main process in the microstructure evolution of the stir zone during the FSP with PAN and EGNS/PAN nanofibers. According to PAN and EGNS/PAN nanofibers were used in the FSP procedure, the grain size reduced as a result of the pinning effects. PAN and EGNS/PAN nanofiber reinforcement enhanced the hardness to 89 and 98 Hv, respectively. Also, the ultimate tensile strength was raised to 291 MPa and 344 MPa, respectively. Tensile strength and hardness of the stir zone increased during the FSP with PAN and EGNS/PAN nanofibers due to the higher density of the strengthening mechanisms of grain boundaries and dislocations. The mechanical characteristics of AA5049 can be enhanced by the procedure of incorporating nanofibers, making them an ideal choice for applications in the automotive and aerospace industries.