1.6356 Maraging Steel Forgings

1.6356 is the German Werkstoff number for an 18% nickel maraging steel of the 350 grade, also written Maraging 350 or 18Ni(350). It is an iron-nickel martensitic steel that gains its strength from intermetallic precipitates of Ni₃Ti and Fe₂Mo formed during ageing, not from carbon. Carbon is held below 0.03%. In the fully aged condition 1.6356 reaches a minimum tensile strength of 2345 MPa and a hardness of up to 56 HRC, which makes it one of the strongest commercially available steels.

1.6356 is a steel, not a nickel-base alloy. Although it contains about 18% nickel, the matrix is iron and the material is classified as an iron-nickel martensitic precipitation-hardening steel, commonly grouped with maraging steels or ultra-high-strength steels rather than with nickel superalloys such as Inconel or Monel.

The three grades differ mainly in cobalt and titanium content, which sets the achievable strength. Maraging 250 (1.6359) contains about 8% cobalt and 0.4% titanium and reaches roughly 1725 MPa tensile. Maraging 300 (1.6358) contains about 9% cobalt and 0.7% titanium and reaches roughly 2000 MPa. Maraging 350 (1.6356) contains about 12% cobalt and 1.4% titanium and reaches a minimum of 2345 MPa. Toughness and ductility fall as strength rises, so 350 has the lowest elongation of the three at about 3% minimum.

No. 1.6356 is not a high-temperature material. It is aged at around 480 °C, and sustained service above roughly 400 °C causes over-ageing and progressive loss of strength. For gas turbine hot sections and other high-temperature service, a nickel-base superalloy such as Inconel 617, Inconel 625 or Haynes 188 should be specified instead. 1.6356 is chosen for ambient and moderate-temperature applications where the highest strength-to-weight ratio and dimensional stability during heat treatment are required.

Jiangyin Jiangnan Metal supplies 1.6356 as open-die forged rings, shafts and spindles, flanges, discs and gear blanks, sleeves and bushings, tube sheets, round bars, blocks and forged tubes. All items are made to customer drawings, with a minimum order quantity of one piece and no tooling charge.

1.6356 is normally supplied solution annealed at 815 to 830 °C and air cooled, which leaves it at about 30 to 35 HRC and easily machinable. The customer then finish machines the part and ages it at approximately 480 °C for three to six hours, which raises the strength to over 2345 MPa with almost no dimensional change. Jiangyin Jiangnan Metal can also supply the forging already aged when finish machining is not required.

Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388 is available on 1.6356 forgings, together with chemical analysis, tensile and yield testing, hardness and dimensional inspection. Material certificates are issued to EN 10204 3.1, or to EN 10204 3.2 countersigned by SGS, BV, TUV, Lloyd's Register or DNV when specified on the purchase order.

Send the drawing or the required dimensions, the delivery condition and the quantity to sales@steelforgepieces.com, or call +86-189-2135-9659. Jiangyin Jiangnan Metal returns a price, forged weight and lead time, normally within 24 hours on working days. The plant is at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China.