4140 Stainless Steel Forged Steel Round Bars Hot Rolled

• Type: Round
• Standard: AISI, ASTM, DIN, JIS, GB, BS
• Composition: Stainless Steel Scrap
• Technique: Forged
• Shape: Bar
• Surface Treatment: Black/Milled/Machined
• Model NO.: round bar
• Special Use: High-strength Steel Plate, Wear Resistant Steel, Silicon Steel, Cold Heading Steel, Free Cutting Steel, Mold Steel
• Application: Die Steel Bar
• Transport Package: Wooden
• Specification: 6-400mm
• Trademark: Smooth
• Origin: China
• HS Code: 7214100000
• Production Capacity: 5000 Ton/Year

Product Description

ASTM 4140 Carbon Alloy Steel Round Bar
4140 is a versatile alloy steel known for its high strength, toughness, and excellent mechanical properties. It belongs to the group of chromium-molybdenum (Cr-Mo) alloy steels and is commonly used in various industrial applications where high strength, good fatigue resistance, and wear resistance are required.

Chemical Composition:

C(%)	Si(%)	Mn(%)	Cr(%)	Mo(%)	P(%)	S(%)
0.38-0.43	0.10-0.35	0.75-1.00	0.80-1.10	0.15-0.25	≤0.030	≤0.030

Properties:
1.High Strength: 4140 steel exhibits high tensile and yield strength, making it suitable for applications requiring load-bearing components and structural parts.
2.Good Toughness: It possesses good toughness and impact resistance, allowing it to withstand sudden shock and vibration without fracturing.
3.Excellent Hardenability: 4140 steel has excellent hardenability, enabling uniform hardness throughout large cross-sections when properly heat treated.
4.Good Fatigue Resistance: It offers good fatigue resistance, making it suitable for applications subjected to cyclic loading and repeated stress.
5.Wear Resistance: 4140 steel exhibits good wear resistance, especially when surface hardened or treated with appropriate coatings.
6.Machinability: While 4140 steel is relatively hard, it can be machined using conventional methods with proper tooling and cutting parameters.
7.Weldability: It can be welded using conventional welding methods, although preheating and post-weld heat treatment may be required to prevent cracking and improve toughness in the heat-affected zone.

Applications:
1.Aerospace: 4140 steel is used in the aerospace industry for manufacturing aircraft components, landing gear, and structural parts requiring high strength and fatigue resistance.
2.Automotive: It finds application in the automotive sector for producing crankshafts, axles, gears, and transmission components subjected to high loads and harsh operating conditions.
3.Oil and Gas: 4140 steel is utilized in the oil and gas industry for manufacturing drill collars, drill pipes, and other downhole tools requiring high strength and corrosion resistance.
4.Tool and Die: It is commonly used in the tool and die industry for making forging dies, extrusion dies, injection molds, and other tooling components requiring wear resistance and toughness.
5.Construction: 4140 steel is employed in the construction sector for producing heavy-duty machinery parts, structural components, and equipment subjected to heavy loads and abrasive environments.
Heat Treatment:
Annealing: Heat uniformly to 815-845°C (1500-1550°F), soak for sufficient time, then slowly cool in the furnace to below 500°C (930°F) followed by air cooling.
Normalizing: Heat uniformly to 870-900°C (1600-1650°F), soak for sufficient time, then air cool to room temperature.
Hardening: Heat uniformly to 845-870°C (1550-1600°F), soak for sufficient time, then quench in oil, water, or polymer to achieve desired hardness.
Tempering: Temper immediately after quenching at 200-650°C (390-1200°F) depending on the desired hardness and toughness requirements, hold for sufficient time, then cool in air.

Surface Treatment:
Various surface treatments such as nitriding, carburizing, and chrome plating can be applied to enhance surface hardness, wear resistance, and corrosion resistance.

Quality Assurance:
Manufacturers of 4140 steel often adhere to international quality standards such as ASTM A29/A29M and ASTM A322 to ensure the quality and consistency of their products.
Quality control measures include chemical composition analysis, mechanical property testing, and non-destructive testing to meet customer specifications and requirements.

Environmental Considerations:
4140 steel is recyclable and can be reclaimed and reused at the end of its service life, contributing to sustainability and environmental responsibility in manufacturing processes.