Maraging steel is a low-carbon, nickel-rich alloy that exhibits good strength and working characteristics without sacrificing malleability. The alloy is based on Martensite steel and is exposed to a protracted heat treatment process known as aging, its name being a combination of the two terms. In addition to its high strength, maraging steel also possesses good welding, hardening and machining characteristics and exhibits solid dimensional stability when heat-treated. Stainless, or corrosion-resistant, grades of the alloy are also possible with the addition of chromium. Due to its good malleability and strength, maraging steel is extensively used to produce weight-sensitive, high-stress parts, including the shells of missiles and rockets and automatic weapon components.
Steel is an alloy based on iron with the addition of various alloying metals, the most common of which is carbon. High-carbon steels are widely-used alloys which exhibit high strength and hardness, but sacrifice malleability or the ability to be bent and formed without breaking. Maraging steel is a low-carbon alloy based on Martensite steel, with nickel as the main alloying component. In addition, the alloy is also exposed to a lengthy heat treatment-process and the addition of secondary alloying agents which include cobalt, titanium and molybdenum. The resultant alloy is exceptionally strong and possesses desirable working qualities with good residual malleability.
The working characteristics of maraging steel, along with its strength, make this alloy a particularly useful one from a manufacturing perspective. Before maraging steel is aged or heat-treated, it can be cold-rolled to a significant extent without cracking and can also be nitrided or case-hardened. The alloy is also easy to machine and very stable when heat-treated, showing very little thermally-induced dimensional change. This allows parts to be machined to their final dimensions prior to hardening. The inclusion of chromium in the alloy also allows for the production of highly corrosion-resistant stainless varieties of the alloy.
The high strength and flexibility of maraging steel makes it an ideal material for the production of the shells or skins of ballistic missiles and rockets. It is also well-suited to the manufacture of high-stress parts exposed to quick thermal cycles such as the firing pins of automatic weapons. The strength and malleability of the alloy also make it a staple in the production of fencing blades. Maraging steel is an ideal material for the manufacture of engine components such as crankshafts due to its inherent toughness. Stainless varieties of the alloy are commonly used to manufacture golf club heads, bicycle frames and even hypodermic needles.