ThePipingMart Blog Grades Alloy Steel UNS K93120 – Composition, Properties and Uses

Alloy Steel UNS K93120 – Composition, Properties and Uses

UNS K93120

In the metal world, UNS K93120 is a popular term you might often encounter. But what exactly is UNS K93120? It is a high-performance austenitic stainless steel with unique physical and mechanical properties. This material is widely used in various industrial applications due to its superior performance. In this blog post, we will look at what UNS K93120 is, its composition, physical and mechanical properties, uses hardness, heat treatment, welding, and corrosion resistance.

UNS K93120 Composition

UNS K93120, also known as Alloy 20, is composed of 33% nickel, 20% chromium, 3% molybdenum, and 5-35% iron. The presence of nickel and chromium makes it highly resistant to chloride-induced stress corrosion cracking, a common problem in many stainless steel alloys. Its molybdenum content adds to its exceptional corrosion resistance, and its high iron content provides good resistance to corrosion in sulfuric acid environments.

Element Content (%)
Iron, Fe 67
Nickel, Ni 18.5
Cobalt, Co 9
Molybdenum, Mo 4.8
Titanium, Ti 0.6
Aluminum, Al 0.1
Silicon, Si 0.10
Manganese, Mn 0.10
Carbon, C 0.030
Zirconium, Zr 0.01
Phosphorous, P 0.010
Sulfur, S 0.010
Boron, B 0.0030

UNS K93120 Physical Properties

UNS K93120 exhibits excellent physical properties, making it an ideal material for many industrial applications. It has a 0.289 lb/in³ density and a melting point of 2440-2530 °F. It has a coefficient of thermal expansion of 8.34 µin/in-°F, which is relatively low compared to other stainless steel alloys. It also has a thermal conductivity of 77.2 BTU/hr-ft-ºF, which is lower than other stainless steel alloys but still adequate for most applications.

Properties Metric Imperial
Density 8.00 g/cm3 0.289 lb/in³
Melting point 1412.8 °C 2575°F

UNS K93120 Mechanical Properties

UNS K93120 has impressive mechanical strength owing to its unique composition. It has a tensile strength of 80 ksi and a yield strength of 35 ksi. It has a high elongation rate of 30%, which means it can withstand significant deformation before breaking. It also has a good hardness level of up to 95 HRB, which makes it suitable for many heavy-duty applications.

Properties Metric Imperial
Tensile strength (@538°C/1000°F) 1158 MPa 168000 psi
Yield strength (@strain 0.200 %, temperature 538°C/@strain 0.200 %, temperature 1000°F) 1056 MPa 153200 psi
Bulk modulus (typical for steel) 140 GPa 20300 ksi
Shear modulus (estimated from elastic modulus) 73.0 GPa 10600 ksi
Elastic modulus 190 GPa 27600 ksi
Poisson’s ratio 0.3 0.3
Elongation at break (in gage length of 4.5 times the square root of the area, @ 316°C/600 °F) 12.00% 12.00%
Reduction of area (@427°C/800°F) 61.30% 61.30%

UNS K93120 Thermal Properties

Properties Metric Imperial
Thermal expansion co-efficient (@21-480°C/69.8-896°F) 10.1 µm/m°C 5.61 µin/in.°F
Thermal conductivity (20°C) 25.3 W/mK 176 BTU in/hr.ft².°F

UNS K93120 Equivalent

  • Equivalent material to UNS K93120 includes DIN 1.6354.

UNS K93120 Uses

UNS K93120 is used in many industrial applications such as chemical, pharmaceutical, food, and petrochemicals. This highly corrosion-resistant material makes it ideal for use in harsh environments exposed to corrosive agents. It is also used in heat exchangers, tanks, pumps, valves, and other equipment exposed to acidic environments.

UNS K93120 Hardness

UNS K93120 has a high hardness level of up to 95 HRB, which means it is a very durable material that can withstand heavy usage without getting damaged. This property is an excellent material for heavy machinery and equipment exposed to heavy loads and abrasion.

UNS K93120 Heat treatment

UNS K93120 is austenitic stainless steel and can be heat-treated by annealing. Annealing improves the ductility and toughness of the material. It involves heating the material to a temperature of 2050°F for 30 minutes, followed by a slow cooling process. This process relieves any stress in the material and makes it easier to shape and form.

UNS K93120 Welding

UNS K93120 can be welded using various methods, such as gas tungsten arc welding (GTAW), shielded metal arc welding (SMAW), and gas metal arc welding (GMAW). The choice of welding method depends on the specific requirements of the application. However, proper welding procedures must be followed to ensure the integrity of the joint.

UNS K93120 Corrosion Resistance

UNS K93120 is highly resistant to corrosion and performs well in acidic environments. Its resistance to stress corrosion cracking, pitting corrosion, and crevice corrosion make it ideal for corrosion-prone applications. It also exhibits good resistance to intergranular corrosion, making it a popular choice in the chemical and pharmaceutical industries.


UNS K93120 is a high-performance austenitic stainless steel that finds widespread use in various industrial applications. Its unique composition and properties make it an ideal material for harsh environments exposed to corrosive agents. It has excellent physical and mechanical properties, high hardness levels, and is highly corrosion-resistant. UNS K93120 is a premium material that offers outstanding value to industrial manufacturers worldwide.

Related Post