ThePipingMart Blog Grades AMS 6529 Alloy Steel – Composition, Properties, and Uses

AMS 6529 Alloy Steel – Composition, Properties, and Uses

AMS 6529

Are you in the search for high-strength alloy steel that can withstand harsh conditions? Look only as far as AMS 6529. This robust alloy steel is utilized in aerospace, defence, and industrial applications. AMS 6529 has excellent physical properties and mechanical strength, making it ideal for various manufacturing processes. This article will cover the composition, physical properties, mechanical properties, uses, hardness, and heat treatment of AMS 6529.

What is AMS 6529?

AMS 6529 (also known as AISI 4140 Alloy Steel) is a specific type of high-strength steel commonly used in the aerospace industry. This unique material boasts exceptional durability and corrosion resistance, making it an ideal choice for applications where reliability is a top priority. With a high level of toughness and resistance to cracking, AMS 6529 steel can withstand extreme temperatures and harsh environments, ensuring optimal performance in even the most challenging conditions. Beyond aerospace, this material is also used in various other industries where strength and resilience are critical. Whether you’re building a rocket or a high-performance engine, AMS 6529 is a material you can count on to deliver impressive results.

What Form is AMS 6529 Available at Piping Mart?

  • Alloy Steel AISI 4140 Bars

AMS 6529 Composition

AMS 6529 is part of the alloy steel family and has high molybdenum, nickel, and chromium content. The composition percentages are as follows: Carbon (0.08-0.13%), Manganese (0.30-0.60%), Silicon (0.15-0.35%), Sulfur (0.025% max), Phosphorus (0.025% max), Chromium (1.00-1.50%), Molybdenum (0.45-0.60%), Nickel (1.40-1.75%). The combination of these metals gives AMS 6529 a high strength-to-weight ratio, excellent resistance to corrosion, and good flexibility.

Element Content (%)
Chromium, Cr 0.80 – 1.10
Manganese, Mn 0.75 – 1.0
Carbon, C 0.380 – 0.430
Silicon, Si 0.15 – 0.30
Molybdenum, Mo 0.15 – 0.25
Sulfur, S 0.040
Phosphorous, P 0.035
Iron, Fe Balance

AMS 6529 Physical Properties

AMS 6529 has impressive physical properties, such as high tensile strength and density. The density of AMS 6529 is 7.85 g/cm3, which makes it heavier than aluminium or titanium. AMS 6529 has a tensile strength of 1900-2100 MPa at room temperature, making it an ideal material for high-stress applications. It also has a specific heat capacity of 470 J/kg°C.

Properties Metric Imperial
Density 7.85 g/cm3 0.284 lb/in³
Melting point 1416°C 2580°F

AMS 6529 Mechanical Properties

The mechanical properties of AMS 6529 are impressive as well. It has a yield strength of 1700-1900 MPa, an elongation of 10-15%, and a reduction of area of 40-45%. These attributes mean AMS 6529 maintains its shape, and it is difficult to deform even under high pressure, making it ideal for manufacturing applications.

Properties Metric Imperial
Tensile strength 655 MPa 95000 psi
Yield strength 415 MPa 60200 psi
Bulk modulus (typical for steel) 140 GPa 20300 ksi
Shear modulus (typical for steel) 80 GPa 11600 ksi
Elastic modulus 190-210 GPa 27557-30458 ksi
Poisson’s ratio 0.27-0.30 0.27-0.30
Elongation at break (in 50 mm) 25.70% 25.70%
Hardness, Brinell 197 197
Hardness, Knoop (converted from Brinell hardness) 219 219
Hardness, Rockwell B (converted from Brinell hardness) 92 92
Hardness, Rockwell C (converted from Brinell hardness. Value below normal HRC range, for comparison purposes only) 13 13
Hardness, Vickers (converted from Brinell hardness) 207 207
Machinability (based on AISI 1212 as 100 machinability) 65 65

AMS 6529 Equivalents

AMS 6349 ASTM A193 (B7, B7M) ASTM A506 (4140) ASTM A752 (4140)
AMS 6381 ASTM A194 (7, 7M) ASTM A513 ASTM A829
AMS 6382 ASTM A29 (4140) ASTM A513 (4140) SAE J1397 (4140)
AMS 6390 ASTM A320 (L7, L7M, L7D) ASTM A519 (4140) SAE J404 (4140)
AMS 6395 ASTM A322 (4140) ASTM A646 (4140) SAE J412 (4140)
AMS 6529 ASTM A331 (4140) ASTM A711

AMS 6529 Uses

AMS 6529 is commonly used to manufacture aerospace components, such as landing gear systems, hydraulic actuators, engine blades, and exhaust systems. It is also used in defence applications such as missiles and satellite structures. Its high strength-to-weight ratio makes it ideal for industrial components such as shafts, gears, and turbines.

AMS 6529 Hardness

AMS 6529 has excellent hardness properties, making it perfect for high wear and tear resistance applications. It has a Brinell hardness of 487-512, which makes it highly resistant to deformation and cracking.

AMS 6529 Heat Treatment

AMS 6529 requires a specific heat treatment process to maintain its excellent physical properties and strength. The heat treatment process includes annealing, hardening, and tempering. During annealing, AMS 6529 is heated to a specific temperature range and held for a specific time to reduce internal stress. After annealing, hardening involves heating the material to an optimal range before cooling it quickly to enhance strength. Finally, tempering reduces brittleness and toughness to optimize the material’s strength-to-weight ratio.


In summary, AMS 6529 material is a high-strength alloy steel with impressive physical and mechanical properties. Its combination of molybdenum, nickel, and chromium makes it highly resistant to deformation, wear, and corrosion. It is ideal for aerospace, defence, and industrial applications requiring high-stress requirements. The heat treatment process ensures AMS 6529 maintains its excellent properties and strength, making it a highly reliable material for manufacturing components.

Related Post