Precision-Engineered A4-80 Stainless Steel Socket Capscrews

A4-80 Stainless Steel Information, Composition & Properties

A4-80 stainless steel is a high-strength, acid-resistant austenitic grade specifically engineered for demanding fastening applications. The designation A4 identifies it as a molybdenum-bearing 316-grade alloy, providing superior resistance to pitting and crevice corrosion in chloride-rich environments, while the 80 denotes a minimum tensile strength of 800 MPa. This enhanced mechanical performance is achieved through a precise cold-working process, making these socket capscrews significantly stronger than standard A4-70 fasteners.

The chemical composition of A4-80 typically includes 16-18.5% chromium, 10-15% nickel, and 2-3% molybdenum. Chromium is essential for creating a protective passive oxide layer, while the high nickel content ensures a stable austenitic structure and excellent toughness, even at cryogenic temperatures. The addition of molybdenum is critical for socket capscrews used in marine or chemical processing environments, as it provides the necessary protection against aggressive localized corrosion that can lead to structural failure in standard stainless steels.

In the context of socket capscrews, the properties of A4-80 are particularly beneficial for high-torque and safety-critical assemblies. With a minimum yield strength of 600 MPa, these fasteners offer the rigidity required to maintain clamp loads under heavy vibration and dynamic stress. Their high-tensile nature allows for the use of smaller or fewer fasteners to achieve the same structural integrity as standard grades, which is often essential for the precision work and close tolerances typically associated with socket drive configurations in offshore, petrochemical, and industrial machinery.

99% on-time delivery

At West Special Fasteners, we deliver precision-engineered fasteners with a proven 99% on-time delivery record, ensuring your projects stay on schedule. With lead times as short as 4 weeks for full-service orders, we provide unmatched reliability for industries where timing is critical.

• Minimise delays – Receive your special fasteners exactly when needed, helping you avoid costly project interruptions.
• Support critical operations – Our dependable delivery is essential for sectors like defence, offshore, and renewables, where timing is non-negotiable.
• Boost project efficiency – Reliable deliveries streamline your workflow, allowing you to focus on execution without supply chain concerns.
• Maintain your reputation – Trust in our punctuality to ensure your commitments to your clients are met, every time.
• Transparent communication – Realistic timelines and proactive updates at every stage.
• Efficient production – Our advanced facilities and streamlined processes enable us to deliver on time, even for complex and bespoke projects.

Our ability to always deliver on time sets us apart in the fastener industry. While with many competitors you can face frequent delays, we ensure your orders are delivered with precision and professionalism – backed by our fully traceable production process and industry-leading expertise.