G. Chandramohan

Friction and Wear Characteristics of Carbon-epoxy and Glass-epoxy Woven Roving Fiber Composites

Polymer materials when reinforced with high modulus fibers yield higher strength, higher stiffness, better toughness, and good dimensional stability. Fiber reinforcements are effective in reducing wear in adhesive situations in addition to increasing the strength and stiffness. The adhesive conditions are generally encountered in automotive and aerospace applications. In such applications, the types of reinforcement material used are important from the point of improved performance under different tribo situations. In this particular investigation, carbon-epoxy (C-E) composite is compared with that of glass-epoxy (G-E) composites for tribological properties using a pin-on-disc set up. The tests are conducted by subjecting C-E samples sliding against a hard steel disc (62 HRC) under different sliding and loading conditions. This article highlights the friction and wear behavior of these composites run for a constant sliding distance, where in the C-E composites show lower friction and lower slide wear loss compared to G-E composites irrespective of the load or speed employed. Some of the wear data are supported by the scanning electron microscope (SEM) images.

Investigation of the Friction and Wear Behavior of Glass-Epoxy Composite With and Without Graphite Filler

Polymeric composites have steadily gained importance in recent years for industrial applications. The increase in use calls for a better understanding of their behavior under different working environments. Friction and wear are considered two important parameters that govern tribological behavior. In this study, the friction and wear characteristics of E-glass-epoxy (G-E) and graphite filler of three different levels in G-E composites were experimentally investigated using a pin-on-disc set-up at varied loads and sliding velocities. From this investigation, it was found that a 7.5 wt% graphite filled G-E composite system showed least coefficient of friction and highest wear resistance compared to the plain G-E composite system, irrespective of the load/speed adopted. Besides conventional weighing, determination of coefficient of friction and examination of worn surface features were undertaken using a scanning electron microscope (SEM) for interpretation of wear behavior.

Three-body Abrasive Wear Behavior of Filled Epoxy Composite Systems:

Particulate filled epoxy composites have been studied for the three-body abrasive wear behavior using the rubber wheel abrasion test (RWAT) apparatus. The epoxy composites were fabricated with 0—20 wt% of the boron carbide in steps of 5wt%. In the present investigation, angular silica sand particles of size in the range 200—250 μm were used as dry and loose abrasives. The wear volume and wear rate were determined as a function of abrading distance. The filler additions have shown significant influence on three-body abrasive wear behavior at different loads. It was observed that inclusion of boron carbide filler in particulate form into epoxy matrix showed improved abrasion resistance. Scanning electron microscopy was used to study the worn surface features to understand the mechanisms involved in the removal of material.

Dynamic mechanical analysis and three-body wear of carbon–epoxy composite filled with SiC particles

The changes that can occur in particulate filled and carbon fabric reinforced epoxy polymer matrix (carbon–epoxy) composites with aging (temperature change) can affect its application, performance, and life time. Fiber and particulate-reinforced composites are known to posses the high strength and attractive wear resistance in dry siding conditions. Though reinforcement and/filler type are known to control the properties, less is known about their abrasive wear performance especially with SiC particulates. How these composites performed in abrasive wear situation needs a proper understanding. Hence in this investigation, reports on dynamic mechanical and three-body abrasive wear behavior of carbon–epoxy and silane-treated SiC particulates filled carbon-epoxy composites. The dynamic mechanical analysis test were conducted using DMA Q800 instrument and abrasive wear tests were conducted using the Rubber wheel abrasive wear tester. From the dynamic mechanical analysis result, it was found that the glass transition temperature (Tg) of 10% SiC-filled carbon–epoxy composite was changed up to maximum 75°C, compared with that of unfilled carbon–epoxy composite. This change in Tg was believed to be due to the interface modification in SiC-filled carbon–epoxy composite. Three-body abrasive wear test results showed that the wear volume loss increased with increasing abrading distance and specific wear rate decreased with abrading distance/load and depends on SiC filler loading. However, the presence of silane-treated SiC in carbon–epoxy showed a promising trend. The worn surface features, when examined through scanning electron microscopy, showed differing trends for unfilled and SiC-filled carbon–epoxy composites.