Alro Steel was established in 1948 by Al and Robert Glick and has grown to include Alro Plastics, Alro Industrial Supply and Alro Metals Outlet.

Alloy Plate

Alloy Plate

What Is An Alloy Plate?

To be classified as an alloy plate, a range or minimum amount of alloying elements such as nickel, molybdenum, chromium, vanadium, etc. is specified or elements are added to obtain an alloying effect. Alloy steel bars and plates are generally given some type of appropriate thermal processing such as annealing or quench and tempering. The addition of alloying elements increases the alloy bar's or plate's hardenability. (Note: alloying elements do not make the metal harder just by their existence in metal, but rather increase the depth to which the alloy bar or alloy plate can be hardened by appropriate heat treatment). The proper alloy can also provide improved fatigue strength in addition to increased wear and toughness.

Alloy metals have the potential to achieve superior combinations of properties not attainable with other metals.

Metal Thermal Processing Alloys

Alro stocks alloy plate in several grades. They are typically annealed or DCF, decarb free. Heat treating can attain required mechanical properties, typically at the expense of machinability. Heat treated bars are often stress relieved. Alloy has the ability to increase hardenability through heat treating. This makes it possible to obtain desired mechanical properties in larger sections.

Alloy Plate Grades and Applications

Alloy Grades Stocked By Alro Include - 

4140 Alloy

4140 alloys are steels in the family of SAE steel grades, as specified by the Society of Automotive Engineers (SAE). 4140 alloys have excellent strength-to-weight ratio and are considerably stronger and harder than standard 1020 steel; however, 4140 is not easily welded and needs pre and post weld thermal treatment to avoid cold cracking.

4140 is typically used for fixtures, stubs, jigs, couplings, gears, and rams. Alro carries alloy bars in 4140 Annealed DCF, 4140 HR Alloy, 4140 HR Annealed, 4140 HR Heat Treated, and 4140 HT DCF.

6150 Alloy

6150 is an electric furnace melt of chrome vanadium steel with a high resistance to vibratory stress and medium hardness. 6150 is typically bought to meet chemistry requirements rather than physical requirements. It is most commonly used in heavy machinery parts, shafts, gears, and high strength studs. Alro carries 6150 in 6150 DCF Annealed and 6150 HR Annealed.

8620 HR

8620 is a low carbon nickel chromium molybdenum alloy steel with good carburized properties.  The nickel content contributes to a high strength case toughness and above average core toughness. 8620 is typically used for shafts, gears, and pinions.


Toolox® 44 is a highly engineered quench & tempered pre-hardened tool and machine steel with measured and guaranteed mechanical properties. Because it does not require heat treating, Toolox® 44 saves you production time and lowers overall costs. Toolox® 44 is easily machined with good dimensional stability. It is typically used in applications requiring toughness and high hardness, including molds, die making, and cold work tooling. Click here to read more about Toolox® 44.

Purchase Alloy Plate

Alro Steel’s network of metals outlets spans 60 locations and 12 states, making it easy to find a metal supplier near you. You can also order your metals online with convenient next-day delivery.