ThePipingMart Blog Grades Alloy Steel Grade 2 1/4CR – Composition, Properties and Uses

Alloy Steel Grade 2 1/4CR – Composition, Properties and Uses

Alloy Steel Grade 2 1/4CR

Alloy Steel Grade 2 1/4CR is a low alloy steel widely used in various industries. It has excellent corrosion resistance, heat resistance, and mechanical properties making it an ideal choice for many applications. In this blog post, we’ll discuss the composition, chemical properties, mechanical properties, physical properties, uses, corrosion resistance, heat resistance, heat treatment and machining of Alloy Steel Grade 2 1/4CR.


The composition of Grade 2 1/4CR consists of carbon (C), manganese (Mn), phosphorus (P), sulfur (S), silicon (Si) and chromium (Cr). The alloy elements present in this grade are chromium and molybdenum. This grade has a high chromium content, providing good wear and tear and excellent corrosion resistance.

Elements Min Max
Fe (Iron ) Bal
Ni (Nickel ) 0 0
Mn (Manganese ) 0.3 0.6
Mo (Molybdenum ) 0.9 1.1
C (Carbon ) 0 0.15
Si (Silicon ) 0 0.5

Chemical Properties

The chemical properties of Alloy 2 1/4CR include high tensile strength, good weldability and ductility. This grade also has good formability and machinability due to its low carbon content. Conventional heat-treating methods can easily harden it without any danger of cracking or losing its properties when subjected to extreme temperatures or pressure.

Mechanical Properties

The mechanical properties of Alloy Steel Grade 2 1/4CR include high yield strength, fatigue strength, and good impact toughness. This grade has excellent corrosion resistance, which makes it suitable for use in highly corrosive environments such as marine applications or those exposed to strong acids or bases. Its high tensile strength also makes it suitable for structural applications such as bridges and automobiles.

Physical Properties

The physical properties of Steel 2 1/4CR include an ultimate tensile strength of 685MPa (100ksi) min., yield strength at 0.2% offset of 497MPa (72ksi) min., elongation at break 15%, reduction area 25%. Its hardness ranges from 201-221 HBW max., while its Charpy Impact Value ranges from 27J min., with no obvious defects visible on the surface after testing according to ASTM A370 standard test method with a hardness tester using a 30kg load on a 10mm indenter for 5 seconds duration time period for each specimen tested.

Designation Tensile strength

ksi [MPa]

Yield strength, min

ksi [MPa]

Elongation in 8 in. [200mm], min %
ASTM A691 Grade 2 1/4 Cr 75-100 [515- 690] 45 [310] 18


Alloy Steel Grade 2 1/4CR is used in various industries, including oil & gas exploration equipment, automotive components, power generation components and, heavy machinery components etc. It is also used in food processing machinery due to its excellent corrosion resistance property, which allows it to resist oxidation even when exposed to harsh chemicals or high temperatures. It can also be used for medical instruments due to its superior machinability and wear and tear resistance compared to other alloys available today.

Corrosion Resistance

The excellent corrosion resistance property of Alloy Steel Grade 2 1/4CR makes it ideal for use in highly corrosive environments like marine applications or those exposed to strong acids or bases without fear of cracking or losing its properties when subjected to extreme temperatures or pressure conditions over extended periods of time without any significant degradation in performance characteristics over extended periods of service life under these conditions.

Heat Resistance

Alloy Steel Grade 2 1/4CR is renowned for having an optimal balance of strength and ductility compared to other grades of alloy steel, but its heat resistance is a major advantage of this grade over others available. Its ability to withstand extreme temperatures without undergoing degradation makes it an ideal choice for many industrial settings and products. Thanks to its heat resistance, operations can be conducted without requiring as frequent shutdowns due to high temperatures. This grade of alloy steel provides the ability for longer run times in processing industries and ensures products remain at peak quality during their entire lifespan.

Heat Treatment

The heat treatment of Alloy Steel Grade 2 1/4CR is an essential process in order to strengthen the material and give it flexibility and increased structural durability. The heat treatment involves heating the steel to its critical point, then cooling it off rapidly between certain temperatures in order to achieve desirable characteristics. It is common to quench with oil or water during this process in order to ensure that the steel remains adequately cooled; however, controlled rate cooling techniques may also be used depending on the intended outcome. Through proper use of Alloy Steel Grade 2 1/4CR heat treatments, engineers can bring out a broad range of properties within the material, such as improved ductility, hardenability, machinability and resistance to wear.


Alloy steel grade 2 1/4CR machining is a complex and delicate process that requires precision and experience. It is designed to create metal parts for various industrial applications, from small valve stems to large press moulds. The challenge with this machining is manipulating the metal’s alloy properties so that the finished product meets exact specifications. After careful selection of material and methods, the process involves cutting the steel with tools such as drills, taps, grinders, and other power tools so that intricate shapes can be created. Indeed, Alloy Steel Grade 2 1/4CR machining is an art form requiring great skill to craft high-quality parts used in countless applications.


Alloy Steel Grade 2 1/4CR Welding is a specialized processing procedure that offers strong welding joints with a high-resistance to corrosive environments. This form of Welding utilizes an advanced combination of shield gases to produce a exceptionally tight and clean weld, making it perfect for projects exposed to harsh climates and landscapes. Aside from offering superior strength, this process also gives users the flexibility of pinpoint accuracy, creating detailed welds that are virtually free from imperfections or structural defects. Users should consider Alloy Steel Grade 2 1/4CR Welding when demanding precision welding in difficult conditions—its efficacy has been proven time and time again.


Alloy Steel Grade 2 1/4CR is a great choice for many applications due to its high strength and excellent resistance to corrosion. It is widely used in the oil and gas industry and in many other industries where strength and durability are important. If you are looking for a reliable and durable alloy steel grade, 2 1/4CR is an excellent option.

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