Alloy steel round bars are high-strength metal rods mixed with elements like chromium, molybdenum, and nickel. Common industry standards include ASTM A182, ASME SA182, and SAE/AISI grades (such as 4140, 4340, and EN19). Standard diameters range from 4 mm to 500 mm, and lengths typically run from 1 to 6 meters. [1, 2, 3, 4, 5, 6] Key Specifications & Standards • Material Standards: ASTM A182 / ASME SA182 (for forged fittings and bars), ASTM A276, EN, DIN, JIS, and BS. • Popular Grades: • Cr-Mo Grades: F5, F9, F11, F12, F22, F91 (high temperature/pressure) • Engineering Grades: SAE 4140, 4340, 8620, EN19, EN24, 20MnCr5 [2, 3, 6] • Size Ranges: • Diameter: 4 mm to 500 mm • Length: 1, 000 mm to 6, 000 mm (custom cut-to-size available) [2, 3, 7] Physical & Mechanical Properties • Form: Round, square, hex, rectangle, or forged billet • Surface Finish: Black (hot rolled), bright polished, rough turned, or matte • Tensile Strength: Varies by grade, typically ranging from 850 MPa to 1, 000 MPa for heat-treated structural/alloy types • Key Traits: High wear resistance, toughness, and ability to withstand high mechanical stress or elevated temperatures. [1, 2, 5, 6, 7] If you can tell me the specific grade (like 4140 or EN19) or the application you need it for, I can provide the exact chemical composition and heat-treatment guidelines you require.