Tungsten alloy rings and lead alloy rings both belong to the category of high-density annular functional components, yet they exhibit fundamental differences in material nature, overall performance, and application boundaries.
Tungsten alloy rings use tungsten as the matrix, with nickel-iron or nickel-copper systems as the binder phase; lead alloy rings are lead-based, typically alloyed with small amounts of antimony, tin, or calcium to improve strength and oxidation resistance. The density of tungsten alloy rings is stably in the range of 17.0–18.8 g/cm3, while lead alloy rings are concentrated around 11.0–11.4 g/cm3. The former has a significantly higher density, giving it a clear mass-per-unit-volume advantage.
Tungsten alloy rings combine high strength with good toughness, offering tensile strength and impact toughness far superior to lead alloys, along with high surface hardness and excellent resistance to wear and deformation. This enables them to maintain shape and positional stability under high-speed rotation, vibration impact, or long-term loading. In contrast, lead alloy rings are relatively soft and prone to creep and fatigue deformation, quickly exhibiting dimensional drift or cracking under dynamic or elevated-temperature conditions.
Radiation shielding performance represents another critical dividing line. The high atomic number and density of tungsten endow tungsten alloy rings with significantly stronger attenuation of γ-rays and X-rays than lead alloys at the same thickness, while being free of lead’s toxicity. Consequently, they have replaced lead alloy rings in medical radiotherapy and nuclear technology facilities.
From an environmental perspective, lead alloy rings pose risks of lead vapor, lead dust, and lead waste contamination throughout their entire life cycle—production, processing, transportation, use, and disposal—presenting long-term threats to operators, patients, and the ecological environment. Tungsten alloy rings, however, are non-toxic, recyclable, and free of radioactive contamination, making them considerably more environmentally friendly.
In terms of machinability, tungsten alloy rings can be precision-machined by turning, milling, and grinding to achieve complex inner/outer diameters, steps, threads, and keyways, and can be reliably welded or interference-fitted with titanium alloys, steels, or carbon fiber. Lead alloy rings, due to their low strength and susceptibility to deformation, can generally only be cast, making high-precision fits and complex functional integration difficult to achieve.
