Search Results

An exploratory study was performed to determine the feasibility of using oriented polypropylene rods as a replacement for metal in side impact beam applications. The study was divided into four phases: (i) laboratory testing of the impact and tensile properties of oriented polypropylene coupons, (ii) design of an oriented polypropylene side impact beam of comparable rigidity to that of a metal beam but with significant weight savings, (iii) development of a means of attaching the polymeric bar to the vehicle and (iv) flexural testing of a scaled down prototype. The oriented polymeric and metal beams exhibited comparable stress-strain behavior during scaled down testing. Although more research is required to validate the design of an oriented polymer side impact beam, the encouraging results suggest that oriented polymers should be considered for use in automotive components that can make use of their high specific strength and stiffness.

Resistive Implant Welding (RIW) is a technology that has the potential to join large thermoplastic automotive components. It involves placing an electrically conductive implant between two parts that are mated under pressure. Heat, dissipated at the interface by direct current, causes melting, flow and ultimately welding to occur. This research examines the RIW of long-glass-fiber reinforced polypropylene (LGF-PP) to continuous-glass-fiber reinforced polypropylene (CGF-PP) using a stainless steel mesh-implant. The effects of welding time, applied current, and weld pressure on the temperature near the mesh, meltdown and the compression-shear strength of the welds were assessed. The results show that it is possible to attain shear strengths of the order of 20 MPa under optimized welding conditions. The meltdown and strength correlate well with a semi-empirical lumped parameter dependent on weld-time, current squared and pressure.