Dose distributions of high-energy electrons into planar and cylindrical layers of low-density polyethylene, high-density polyethylene, poly(vinyl chloride), and copper for industrial applications

摘要

High-energy electron irradiation of low-density polyethylene, high-density polyethylene, plasticized poly(vinyl chloride) (PPVC), and copper (Cu) of various thicknesses were studied. We measured the dose distributions versus the thicknesses of various layers of these materials. Moreover, we irradiated polyethylene-Cu-polyethylene and PPVC-Cu-PPVC sandwiches and electrical conductors with Cu cores having 1.4-4.8-mm diameters and polymeric (polyethylene and PPVC) insulation 0.6-1.1 mm thick. The irradiation was carried out with 5 and 10 MeV of electrons. The depth-dose distributions for these materials showed that 10 MeV of electrons penetrated polyethylene (up to R-p similar to 4.5 cm), PPVC (up to R-p similar to 3.5 cm), and Cu (up to Rp similar to 5 mm). For the sandwiches (planar geometry), the largest dose levels were at the surfaces of the polymeric insulation materials close to the Cu sheets. For small wires, one-sided irradiation gave a relatively uniform dose distribution, especially with 10 MeV of electrons, and excellent uniform dose distribution was obtained by two-sided irradiation. For wires with comparatively thick insulation, two-sided irradiation with 5 MeV of electrons provided a relatively uniform dose distribution, and a more uniform distribution for this type of wire and cable was achieved by irradiation from four sides and with 10 MeV of electrons. (C) 2003 Wiley Periodicals, Inc. [References: 15]