1. Key Properties:
High Strength: SAE 4125 is an alloy steel with excellent tensile and yield strength, making it well-suited for high-pressure and high-stress applications.
Good Toughness: Known for its toughness, it is resistant to impact and shock loads, ensuring reliability under harsh conditions.
Weldability: This steel offers good weldability, making it versatile for various fabrication processes and structural applications.
Corrosion Resistance: Provides moderate resistance to corrosion, ideal for general industrial environments, though it may require protective coatings in harsh conditions.
Heat Treatable: SAE 4125 can be heat treated to increase hardness and strength, offering flexibility for more demanding uses.
2. Applications/Industries:
Automotive: Used in the production of high-strength automotive components like shafts, gears, axles, and other parts requiring resistance to wear and heavy loads.
Heavy Machinery: Ideal for heavy-duty components such as crankshafts, connecting rods, and structural parts that are subject to fatigue and stress.
Oil & Gas: Commonly used in drilling equipment, pipelines, and high-pressure systems in the oil and gas industry.
Aerospace: Employed for non-critical aerospace components that require high strength and toughness, such as engine parts, structural elements, and landing gears.
Hydraulic Systems: Suitable for hydraulic cylinders, rods, pistons, and other components that need to withstand high pressure and require good machinability.
3. Certifications/Standards:
SAE J403: SAE 4125 conforms to the SAE J403 standard for alloy steels, ensuring it meets specific mechanical and chemical properties.
ASTM A519: This specification applies to seamless carbon and alloy steel mechanical tubing, relevant for SAE 4125.
ISO 9001: Quality management system certification.
4. Chemical Composition:
Carbon (C): 0.23% – 0.28%
Manganese (Mn): 0.60% – 0.90%
Chromium (Cr): 1.00% – 1.40%
Molybdenum (Mo): 0.15% – 0.25%
Silicon (Si): 0.20% max
Phosphorus (P): 0.035% max
Sulfur (S): 0.035% max
Iron (Fe): Balance
5. Technical Specifications:
Yield Strength:
SAE 4125: 450 MPa (minimum)
Tensile Strength:
SAE 4125: 590–735 MPa
Hardness:
SAE 4125: Approximately 197–255 HB (Brinell hardness)