ASTM B524 governs concentric-lay-stranded conductors made from:
Outer Layer: Round aluminum 1350-H19 wires (extra hard temper).
Core Wires: Round aluminum-alloy 6201-T81 wires (hard temper: solution heat-treated, cold-worked, artificially aged).
Designed exclusively for overhead electrical conductors in transmission and distribution systems.
Construction Requirements:
Compliant mass, mass per unit length, reel sizes, and shipping lengths.
Wire Testing:
Physical, mechanical, and electrical properties verified, including:
Density (SI units standard)
Cross-sectional area
Breaking strength
Mass electrical resistance
Units:
Inch-pound units are primary standard for most properties.
SI units govern density, resistivity, and temperature (mandatory).
Mixed unit systems are prohibited.
Material Specifications:
Aluminum 1350: Conforms to UNS A91350 (Practice E527).
Alloy 6201: Conforms to UNS A96201 (ANSI H35.1 temper designations).
Fabrication Process:
Core wires undergo:
Solution heat treatment → Cold working → Artificial aging.
Optimized Conductivity-Strength Balance:
Aluminum 1350 provides electrical efficiency; alloy 6201-T81 core delivers mechanical reinforcement.
Corrosion Resistance:
Aluminum-alloy core eliminates steel galvanic corrosion risks.
Thermal Stability:
Artificially aged core maintains performance from -40°C to 80°C.
Global Compliance:
Aligns with WTO/TBT Committee international standardization principles.
Overhead Power Transmission Lines:
High-voltage conductors (≥69 kV) requiring lightweight strength.
Critical Environments:
Coastal grids (salt corrosion resistance).
Mountainous terrain (ice/wind load resilience).
Long-span river crossings (fatigue resistance).
Distribution Networks:
Retrofits of aging infrastructure needing higher capacity.
