An alloy steel is a steel that contains one or more alloying elements (not including carbon) in its composition to improve physical and/or mechanical properties. The most common alloying elements are silicon, manganese, nickel, copper, titanium, molybdenum, boron, and chromium. The result of adding these elements produces new and/or increased properties not regularly found in carbon steels. Alloy steels are typically divided into different groups: low-alloy steel and high-alloy steel.
Alloy Steel Grades:
4140 Heat Treated (HT) – 4140 Annealed
4140 Heat Treated (HT) Alloy Steel
4140 Heat Treated is a chromium-molybendium alloy steel. 4140 HT is the most commonly used high tensile steel with endless applications including everything from gears and pumps to various applications in the automotive and construction industry. 4140 HT has a medium hardness of 28/32 HRC.
4140 Annealed Alloy Steel
4140 Annealed is also a chromium-molybdenum alloy steel. 4140 Annealed is often used when high tensile strength or toughness is required. 4140 Annealed will have a hardness in the high teens/low twenties on the Rockwell C Scale.