Lead (Pb)
Lead is one of the densest common metals, prized for its exceptional radiation shielding, acid resistance, and sound dampening properties. Despite health concerns limiting many traditional uses, lead remains critical for batteries (85% of consumption), radiation protection, and specialized chemical applications.
Properties
- Density
- 11,340 kg/m³
- Melting Point
- 327 °C
- Boiling Point
- 1,749 °C
- Thermal Conductivity
- 35.3 W/(m·K)
- Electrical Resistivity
- 2.08 × 10⁻⁷ Ω·m
- Tensile Strength
- 12–18 MPa
- Yield Strength
- 8–11 MPa
- Hardness
- 3–5 HB
- Elongation
- 40–60%
- Crystal Structure
- FCC
Common Grades
- Pb 99.99% (Corroding): High-purity lead for chemical and radiation shielding applications.
- Pb-Sb (Antimonial): Lead-antimony alloy (1–12% Sb). Battery grids, cable sheathing.
- Pb-Sn (Solder): Lead-tin alloys. Traditional soldering (being phased out by RoHS lead-free mandates).
- Pb-Ca (Calcium Lead): Maintenance-free battery grids. Lower gassing, improved cycle life.
Applications
- Batteries: Lead-acid batteries for vehicles, UPS systems, telecommunications, solar storage
- Radiation Shielding: X-ray rooms, nuclear facilities, CT scanners, radiotherapy bunkers
- Chemical Processing: Acid-resistant linings, sulfuric acid piping, electrowinning anodes
- Construction: Roofing flashings, sound insulation, vibration damping, seismic isolation
FAQ
Why is lead used for radiation shielding?
Lead's high atomic number (82) and extreme density (11,340 kg/m³) make it highly effective at attenuating X-rays and gamma radiation. A 1mm sheet of lead reduces radiation intensity significantly. It's cost-effective and easily formed into sheets, bricks, and custom shapes for medical and nuclear facilities.
Is lead being phased out?
Lead has been eliminated from paints, petrol, and most consumer products. However, it remains essential and growing in batteries (lead-acid batteries are 99% recyclable), radiation shielding, and specialized industrial applications. Lead-acid battery demand is still increasing globally despite lithium-ion growth.
Are lead-acid batteries still relevant in the lithium-ion era?
Yes — lead-acid batteries still dominate automotive starting (SLI), UPS systems, and telecommunications backup due to low cost, proven reliability, and 99% recyclability. Global lead-acid battery production continues to grow at ~3% annually. Lithium-ion is taking share in EV traction and portable electronics, but lead-acid remains dominant by total installed GWh.