Dimensional Range

Standard length: approximately 6 m. Custom lengths can be supplied to meet project specifications.

AISI 5140 is a chromium-alloy structural steel prized for its balanced combination of hardenability and machinability. This grade responds well to heat treatment, allowing manufacturers to tailor its mechanical properties for specific applications. Commonly used in the automotive industry, it appears in components such as axles, gears, shafts, and bolts that require moderate strength and good wear resistance. The material can be processed through hot rolling, cold rolling, or forging, and is available in round, flat, square, and hexagonal shapes. Its versatility and consistent performance under stress make it a reliable choice for machinery parts across many industrial sectors.

Equivalents to AISI 5140 include 40Cr under the GB standard, SCr440 in the JIS system, and 41Cr4 under EN specifications. These cross-references allow engineers and buyers worldwide to source comparable material regardless of regional classification systems. The alloy's chromium content enhances its hardenability and contributes to improved strength after quenching and tempering. This global recognition means that manufacturers can specify AISI 5140 or its equivalent designations with confidence, knowing that the material will meet established performance benchmarks across different markets and regulatory environments.

Heat treatment plays a crucial role in unlocking the full potential of AISI 5140 alloy steel. Typical processes include quenching followed by tempering at appropriate temperatures to achieve desired hardness and toughness levels. The steel may also be normalized or annealed depending on the intended application and required microstructure. Proper heat treatment ensures that finished components exhibit consistent mechanical properties, dimensional stability, and resistance to fatigue. Manufacturers rely on precise temperature control and cooling rates to produce parts that meet stringent quality standards for demanding automotive and industrial uses.

The surface quality and dimensional accuracy of AISI 5140 bars are important factors for downstream machining and fabrication. Whether supplied in hot-rolled condition for rough machining or cold-drawn for tighter tolerances, the material can be further processed through turning, milling, drilling, and grinding. Its machinability is rated favorably among medium-carbon alloy steels, especially when supplied in the annealed condition. This ease of machining translates to reduced tool wear and shorter cycle times in production environments, making AISI 5140 an economical choice for high-volume manufacturing of precision components.

Jianhui Metals Group maintains a comprehensive inventory of AISI 5140 alloy steel bars to serve clients in automotive, machinery, and general engineering sectors. As a leading supplier based in China, the company has established a strong reputation across overseas markets in Europe, Asia, Africa, South America, and Oceania. The focus remains on providing customers with competitive pricing and timely deliveries while meeting industry-standard specifications. Continuous investment in quality control and material sourcing ensures that every shipment meets the rigorous demands of modern manufacturing applications worldwide.

Typical Applications

AISI 5140 / 40Cr is commonly used in the manufacture of medium-duty mechanical parts that require good wear resistance and toughness:

• Gears and gear shafts
• Steering knuckles and steering arms
• Crankshafts and connecting rods
• Bolts, studs, and fasteners
• Machine tool spindles