Vehicle Body of Ganesha Underwater Scooter: Toughness Characteristics of Polyester Matrix Composite Hybrid Reviewed from Variation of Rami Fiber Volume Fraction

This study aimed to determine the influence of fiber volume fraction towards composite toughness and the composite hybrid fracture pattern models reinforced by hemp fiber and fiberglass to find out the ratio of composite toughness from variation of hemp fiber volume fraction and fiberglass A1 (15 : 25), A2 (20 : 20), A3 (25 : 15)%. This research is an experimental method research with the dependent variable is composite toughness and the independent variable is the fiber volume fraction. Based on the test and data analysis, the results for fraction A1 (15 : 25)% have the greatest impact absorption of 10834.6 J/m2 compared to A2 (20 :20)% that have absorption of 8470.828 J/m2 and A3 (25 : 15)% is 7168.813 J/m2. The most prominent one of the three variations of volume fractions on this fracture pattern analysis is the existence of (delamination) or there are fibers which are not perfectly exposed to the matrix. The Delamination usually occurs due to overly tightening of the fibers.

Effect of Deep Penetration of Interleaf on Delamination Resistance in GFRP

The problem of improving the delamination resistance and toughness of laminate fiber-reinforced composites especially for the drop-off structure is receiving considerable attention with the increasing need and application in industries. A hot melt-bonding process is developed to bond glass fabric laminates and the thermoplastic (TP) polysulfone (PSU) interleaf prior to the vacuum assisted resin transfer molding (VARTM) of laminate composites. The TP interleaf is heated above the glass transition temperature to reduce the viscosity when penetrating deeply into the glass fiber fabric. Mechanical tensile testing is performed to quantify the effects of the penetration depth on composite delamination resistance and composite toughness under different melt-bonding temperatures. Crack paths are observed by optical microscopy to characterize the crack propagation and arrest mechanism. Postmortem high-resolution imaging of the fracture surfaces is used to characterize the toughening mechanism of the TP interleaf reinforcements by using scanning electron microscopy (SEM). With deep penetration of the interleaf into the fiber bundles, cracks arrested within the penetration region improve the toughness by avoiding the cracks to reach the weak interface between interleaf and epoxy.

ZrO2-TiN Composites

1.75 mol % Y2O3-stabilized ZrO2-based composites with 35-95 vol % TiN were fully densified by hot pressing for 1 hour at 1550°C under a load of 28 MPa. The TiN grain size was found to increase with increasing TiN content, resulting in a decreasing hardness and strength. The best mechanical properties, i.e., an indentation toughness of 5.9 MPa.m1/2 in combination with a Vickers hardness of 14.7 GPa and an excellent bending strength of 1674 MPa were obtained for the composites with 40 vol % TiN. The active toughening mechanisms were identified and their contribution to the overall composite toughness is discussed. Transformation toughening was found to be the primary toughening mechanism in all investigated composites.

Interactions between toughening mechanisms: Transformation toughening versus plastic deformation

In this study, the interactions between transformation toughening and plastic stretching were investigated experimentally. Zirconia and metals, nickel or silver, were incorporated simultaneously into an alumina matrix. The extent of phase transformation of zirconia particles was enhanced due to the coexistence of soft metals. The ductility of nickel was also enhanced in the Al2O3–Ni–ZrO2 composites. However, the presence of zirconia particles at the alumina/silver interface reduced the ability of silver to deform plastically. Due to the interactions, the ratio of composite toughness to matrix toughness for the Al2O3–Ni–ZrO2 composite was higher than the product of the ratio of the composites containing only nickel and only zirconia.