The LAJIAOZ 4140 Alloy Steel Round Bar is a high-performance industrial-grade steel rod crafted from premium 4140 Chromoly steel. Measuring 1.5 inches in diameter and 36 inches in length, this round bar features a cold finished surface for improved dimensional precision and an annealed core for superior ductility and machinability. Engineered for high-stress, heavy-duty environments, 4140 steel offers outstanding strength, impact resistance, abrasion resistance, and fatigue durability. This makes it a popular choice for a wide range of mechanical parts including gears, shafts, spindles, valves, sprockets, and collars. Suitable for machining, welding (with post-weld heat treatment if hardened), and heat treatment, this steel bar is an essential material for professionals in aerospace, automotive, oil & gas, defense, and agricultural industries. Whether you're fabricating custom components or replacing critical parts, this alloy steel round bar delivers reliable performance that meets ASTM A108 standards.