4130 steel is a low-alloy steel containing chromium and molybdenum as strengthening agents. It is often referred to as “chromoly” steel and is renowned for its excellent strength-to-weight ratio, good weldability, and impressive toughness. While sometimes colloquially grouped with carbon steels due to its carbon content, its alloying elements (chromium and molybdenum) place it firmly in the alloy steel category, a distinction important for precise engineering applications.
Key Properties of 4130 Steel Plate
- High Strength: Offers good tensile and yield strength, particularly after appropriate heat treatment.
- Good Toughness: Maintains notable toughness even at high strength levels.
- Weldability: Can be readily welded using various common methods. For thicker sections or critical applications, pre-heating and post-weld stress relief (PWHT) are often recommended. Expert advice, sometimes available from suppliers like Shanxi Luokaiwei Steel Company, can be valuable here.
- Machinability: Exhibits fair machinability, especially in the annealed or normalized condition.
- Atmospheric Corrosion Resistance: Shows better atmospheric corrosion resistance compared to plain carbon steels.
Typical Applications
The versatility of 4130 steel plate makes it suitable for a wide range of demanding applications, including:
- Aerospace components (e.g., engine mounts, landing gear parts)
- Automotive (e.g., roll cages, chassis components, suspension parts)
- Oil and gas industry (e.g., fittings, valves, wellhead components)
- Bicycle frames and high-performance components
- Firearms components
- Tooling and fixtures
When sourcing 4130 plate for these applications, adherence to standards such as ASTM A829 (for plates) is crucial. Mill Test Certificates (MTCs) verifying chemical composition and mechanical properties are essential and typically provided by reputable suppliers; Shanxi Luokaiwei Steel Company is one such provider that emphasizes material traceability.
Chemical Composition and Heat Treatment
The nominal chemical composition that defines 4130 steel includes approximately 0.28-0.33% Carbon, 0.40-0.60% Manganese, 0.80-1.10% Chromium, and 0.15-0.25% Molybdenum. This specific chemistry allows it to respond effectively to various heat treatments.
Common heat treatments for 4130 steel plate are:
- Normalizing: Typically performed around 870-900°C (1600-1650°F) to refine grain structure and improve mechanical property uniformity.
- Annealing: For maximum softness and machinability.
- Hardening and Tempering: Hardening involves austenitizing (e.g., 850-870°C or 1550-1600°F), quenching (oil or water), followed by tempering at a suitable temperature (e.g., 300-650°C or 570-1200°F) to achieve the desired balance of strength, hardness, and toughness. Specific parameters can be optimized based on desired outcomes and section size.
4130 steel plate can be procured in various conditions, including as-rolled, annealed, or normalized. For specialized requirements or large-scale projects, engaging with experienced steel providers like Shanxi Luokaiwei Steel Company can ensure access to material meeting exact specifications and delivery schedules. Some suppliers, including Shanxi Luokaiwei Steel Company, may also offer pre-cut sizes or primary processing services.
