ThePipingMart Blog Grades SAE/AISI 5145 Alloy Steel (G51450) – Composition, Properties and Uses

SAE/AISI 5145 Alloy Steel (G51450) – Composition, Properties and Uses

SAE/AISI 5145 Steel

AISI 5145 steel is a versatile alloy often used in the automotive and mechanical engineering industries. 5145 Alloy Steel offers excellent corrosion resistance, heat resistance, and machinability. SAE/AISI 5145 Alloy Steel, also known as UNS G51450, is a highly versatile steel widely used in various industrial applications. With its excellent combination of strength, toughness, and hardness, SAE-AISI 5145 steel is known for its exceptional resistance to wear and tear, making it a popular choice for manufacturing gears, shafts, axles, and other components that are subjected to heavy loads and high stress. In terms of composition, AISI 5145 is a low-carbon alloy steel containing chromium, molybdenum, and nickel, contributing to its exceptional mechanical properties. With its outstanding strength and durability, SAE 5145 steel is a reliable choice for any project that requires top-quality steel. This blog post will explore each aspect of G51450 steel to help you decide if it’s right for your next project.

What Forms of AISI 5145 is Available at Piping Mart?

  • Nut
  • Bar
  • Bolt
  • Pipe
  • Screw
  • Tubing
  • Valves
  • Washers
  • Flanges
  • Fasteners
  • Electrodes
  • Stud Bolts
  • Sheet Plates
  • Pipe Fittings
  • Forged Fitting
  • Instrumentation Fittings

AISI 5145 Composition

Element Weight %
C  0.43-0.48
Mn  0.70-0.90
P  0.035 (max)
S  0.04 (max)
Si  0.15-0.30
Cr  0.70-0.90

AISI 5145 Physical Properties

Physical Properties Metric English Comments
Density 7.85 g/cc 0.284 lb/in³ Estimated by MatWeb from very similar grade

AISI 5145 Mechanical Properties

Properties  Conditions
T (°C) Treatment
Density (×1000 kg/m3) 7.7-8.03 25
Poisson’s Ratio 0.27-0.30 25
Elastic Modulus (GPa) 190-210 25

AISI 5145 Uses

SAE/AISI 5145 steel is often used in the automotive and mechanical engineering industries. It’s well-suited for use in components like crankshafts, gears, shafts, axles, cams, connecting rods, bushings, transmission parts, and other machined parts. It’s also frequently used in agricultural equipment and oil & gas industry applications.

AISI 5145 Uses in Industries

Automotive Industry

One of the most common uses of AISI 5145 steel is in the automotive industry. This type of steel is often used to make various components such as gears, shafts, and axles due to its high strength, wear resistance, and toughness. It is also used in suspension systems and steering columns.

Construction Industry

AISI 5145 steel is also widely used in the construction industry for its high strength and durability. It is commonly used to make structural components such as beams, columns, and support frames for buildings and bridges. Its toughness also makes it ideal for use in heavy-duty construction equipment.

Aerospace Industry

The aerospace industry also utilizes AISI 5145 steel for its high strength-to-weight ratio and ability to withstand extreme temperatures. It is commonly used in aircraft landing gear, engine parts, and other critical components requiring strength and lightweight.

Oil and Gas Industry

In the oil and gas industry, AISI 5145 steel is often used to make drill collars, essential tools for drilling deep into the earth’s surface. This type of steel’s high strength and toughness make it well-suited for withstanding the intense pressure and stress of drilling operations.

Marine Industry

In the marine industry, due to its corrosion resistance properties, AISI 5145 steel is commonly used to make shipbuilding components such as propeller shafts, rudders, and keels. It can withstand exposure to saltwater without corroding or weakening over time, making it an ideal choice for marine applications.

AISI 5145 Corrosion Resistance

SAE/AISI 5145 steel has excellent corrosion resistance due to its high chromium content (14%). This makes it an ideal choice for parts that will be exposed to moisture or harsh chemicals during operation. Its corrosion resistance also makes it suitable for use in food processing applications where hygiene is important.

AISI 5145 Heat Resistance

SAE/AISI 5145 steel has excellent heat resistance thanks to its high carbon content (0.48-0.53%). This allows it to maintain its strength even at elevated temperatures, making it perfect for high-temperature applications like exhaust manifolds and turbochargers.

AISI 5145 Heat Treatment

SAE/AISI 5145 steel can be heat treated to increase its strength and ductility as well as improve its wear resistance characteristics. The most common heat treatment techniques are normalizing and annealing, which involves heating the metal until it reaches a specific temperature before allowing it to cool slowly at room temperature or under controlled conditions such as air cooling or quenching with oil or water, depending on the desired results. Heat treating should always be done by a professional who is familiar with the process to ensure optimal results are achieved without damaging the material properties of the metal itself.

AISI 5145 Machining

SAE/AISI 5145 steel has good machinability making it easy to work with using conventional machining methods such as drilling, tapping, milling, and turning operations without requiring specialized tools or extra effort from operators. This makes it a cost-effective option for manufacturing components quickly and accurately with minimal waste material generated during processing operations.

AISI 5145 Welding

Welding of SAE/AISI 5145 steel is becoming increasingly popular in industrial and manufacturing applications due to its superior strength, hardness, and wear properties. These properties make it a suitable choice for use in components like automobile frames, heavy machinery parts, machine tools, and more. To maximize its potential benefits, welders often rely on various specific welding procedures, including shielded metal arc welding (SMAW), gas metal arc welding (GMAW), submerged arc welding (SAW), flux-cored arc welding (FCAW), and oxyfuel cutting or oxy-acetylene welding. Adopting the right technique will ensure minimal risk of discontinuities such as cracks or porosity while allowing the durable attributes of SAE/AISI 5145 steel to be fully realized.


With its excellent corrosion resistance, heat resistance, machinability, and weldability, SAE / AISI5 145 steel is an ideal choice for many different types of projects ranging from automotive parts to oil & gas industry components and more! Whether you’re looking for a reliable material for your next project or just want to learn more about this versatile alloy, this blog post should have given you all the information you need about what makes this alloy so special! Thanks for reading!

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