ThePipingMart Blog Grades Stainless Steel AM 350 – Composition, Properties And Uses

Stainless Steel AM 350 – Composition, Properties And Uses

AM 350

Stainless steel has gained immense popularity in recent times due to its corrosion-resistant properties. AM 350 is an aged-hardening martensitic stainless steel that has excellent mechanical properties due to its high strength and hardness. This blog post will take you through the composition, physical and mechanical properties, and other applications of AM 350.

AM 350 Composition:

AM 350 is an iron-based alloy with 15% to 17% chromium and 2.5% to 4.5% nickel. It also comprises significant quantities of copper and molybdenum. These elements contribute to its high strength and corrosion resistance.

Element Content (%)
Iron, Fe 63
Nickel, Ni Balance
Cobalt, Co 12
Molybdenum, Mo 4.8
Titanium, Ti 1.4
Aluminum, Al 0.1
Manganese, Mn ≤ 0.10
Silicon, Si ≤ 0.10
Carbon, C ≤ 0.030
Sulfur, S ≤ 0.010
Phosphorous, P ≤ 0.010
Zirconium, Zr 0.01
Boron, B 0.003

AM 350 Mechanical Properties:

AM 350 offers high mechanical strength and hardness, making it suitable for various applications such as aerospace components, shafts, gears, and valve parts. Its ultimate power ranges from 180ksi to 200ksi, with a yield strength of 140ksi to 170ksi. AM 350 possesses high toughness and ductility, making it an all-rounder stainless steel. Its elongation is between 10% to 15% and exhibits an impact strength of 200J to 300J.

Properties Metric Imperial
Tensile strength 1140 MPa 165000 psi
Yield strength (@ strain 0.200%) 827 MPa 120000 psi
Bulk modulus (typical for steel) 140 GPa 20300 ksi
Shear modulus (estimated from elastic modulus) 77 GPa 11200 ksi
Elastic modulus 200 GPa 29000 ksi
Poisson’s ratio 0.3 0.3
Elongation at break (in gage length 4.5 times the square root of the area) 18% 18%
Reduction of area 70% 70%

AM 350 Physical Properties:

AM 350 offers excellent physical properties such as high thermal conductivity and low thermal expansion coefficient. It has a density of 7.8 g/cm3, and its melting point ranges from 1480°C to 1505°C.

Properties Metric Imperial
Density 8.08 g/cc 0.292 lb/in³

AM 350 Thermal Properties

Properties Metric Imperial
Thermal expansion co-efficient (@ 21-480°C/69.8-896°F) 11.3 µm/m°C 6.28 µin/in°F
Thermal conductivity (@20°C) 25.3 W/mK 176 BTU in/hr.ft².°F

AM 350 Equivalent

  • DIN 1.6355
  • DIN 1.6356

AM 350 Uses

AM 350 is a high-strength, corrosion-resistant alloy that has found many uses across various industries. Thanks to its exceptional strength and durability, AM 350 is perfect for use in aircraft and marine applications, where it is required to withstand harsh conditions. Additionally, AM 350 is also a popular choice in the nuclear energy sector, where its resistance to radiation makes it ideal for use in reactors. Overall, AM 350’s versatility and resilience make it one of the most sought-after alloys on the market, and its uses are only set to grow in the future.

AM 350 Corrosion Resistance:

AM 350 exhibits superior corrosion resistance in various environments, such as saltwater, acids, and high temperatures. Due to its high chromium and nickel content, it is highly resistant to pitting corrosion. Besides, the addition of molybdenum and copper enhances its resistance to sulfide stress corrosion cracking (SSCC) and intergranular corrosion (IGC).

AM 350 Heat Treatment:

AM 350 is often solution-treated or annealed at high temperatures of 1010°C to 1100°C. It is then air-cooled to form a soft austenitic structure. Afterwards, it is aged at temperatures ranging from 425°C to 450°C. The ageing process increases its hardness and strength.

AM 350 Machinability:

AM 350 has fair to excellent machinability that depends on its hardness. In the annealed condition, it has excellent machinability. However, in the aged-hardened state, it becomes hard and needs cutting tools with carbide tips.

AM 350 Welding:

AM 350 can be readily welded using conventional welding techniques such as gas tungsten arc welding (GTAW) and gas metal arc welding (GMAW). Preheat and post-weld annealing help prevent cracking and stress corrosion cracking.


AM 350 is a versatile stainless steel alloy that offers high strength, toughness, and corrosion resistance. Its excellent physical and mechanical properties make it suitable for various applications such as shafts, gears, valve parts, and aerospace components. Its heat treatment, machinability, and welding properties make it an all-rounder stainless steel. Hence, AM 350 is an excellent choice for those seeking corrosion-resistant and high-strength stainless steel.

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