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The performance of lead boron polyethylene sheet revolves around three dimensions: radiation protection, mechanical strength, and environmental adaptability, meeting the stringent requirements of complex radiation conditions
1. Radiation protection performance (core indicators)
Neutron protection: Fast neutron slowing efficiency of 95%, thermal neutron absorption rate of 80%, and boron-10 isotope with a thermal neutron absorption cross section of up to 3837 microns, far superior to traditional materials
γ Radiation protection: Board with 30% lead content, 10mm thickness for 1MeVγ Radiation attenuation rate of 50% is equivalent to the shielding effect of a 2mm pure lead plate, and there is a risk of lead-free poisoning
No activation characteristics: The material itself does not produce radioactive activation products, and there is no secondary radiation pollution after use, making it safer
2. Physical and mechanical properties
Density: 1.05-1.30g/cm3³ Only 1/3 of concrete and 1/11 of pure lead, significantly reducing structural load, and allowing a single person to transport thin panels
Mechanical strength: tensile strength 18-25MPa, bending strength 30-40 MPa, impact strength≥ 20kJ/m² Can withstand equipment vibration and slight impact
Temperature resistance range: -40 ℃ to 80 ℃, short-term (1 hour) can withstand high temperature of 100 ℃, no risk of brittle fracture in low temperature environment, and no softening deformation under high temperature
Friction coefficient: 0.3-0.4, smooth surface, easy to clean and maintain, not prone to dust and dirt accumulation
3. Chemical and Environmental Adaptability
Corrosion resistance: resistant to most acids, bases, salts, alcohols, esters, hydrocarbons, but not resistant to strong oxidants such as nitric acid and fuming sulfuric acid, suitable for the complex environment of chemical and nuclear facilities
Low water absorption: Water absorption rate<0.01%, no dimensional deformation or performance degradation when used in humid environments, excellent dimensional stability
Electrical insulation: Volume resistivity 10¹ ?Ω Above cm, suitable for radiation protection around electrical equipment, with no risk of conductivity