Stainless Steel – Grade 384 (UNS S38400)

For making the correct choice of metal for any application, we require a thorough knowledge of the material to base the choice on. It may include knowledge about properties, composition, and applications. While selecting a particular grade of stainless steel you must know about its properties.

In this article, let us explore grade 384 stainless steel, its chemical composition, applications, and properties.

Let us get on the journey to explore all you need to know about 384 stainless steel!

About Grade 384 Stainless Steel

Grade 384 stainless steel is a high-quality stainless steel belonging to the family of 400 series. It is similar to stainless steel grade 410 but has an extra dose of molybdenum, a special element added to increase its strength, and corrosion resistance. Therefore, it becomes much more suitable for applications requiring enduring properties.

AISI 384 Stainless Steel

AISI 384 stainless steel is majorly composed of the following key elements: carbon, manganese, phosphorus, sulfur, silicon, chromium, nickel, and molybdenum. AISI 384 consists of molybdenum that improves its resistance to pitting and crevice corrosion, making it suitable for applications where other common grades are not suitable.

Iron, Fe

63%

Nickel, Ni

18%

Chromium, Cr

16%

Manganese, Mn

2.0%

Silicon, Si

1.0%

Carbon, C

0.080%

Phosphorous, P

0.045%

Sulfur, S

0.030%

 

Physical Properties of Grade 384 Stainless Steel

Stainless steel Grade 384 has a density of 8.00 grams per cubic centimetre, making it quite heavy in proportion to volume. It has a melting point of approximately 1400 degrees Celsius, thus making it highly heat resistant. It also shows high conductivity to both heat and electricity and hence is a good choice for several industries. Besides, Grade 384 stainless steel shows magnetic permeability and gets magnetized easily. 

 

Density

8.00 g/cm3

Mechanical Properties of Grade 384 Stainless Steel

Grade 384 stainless steel contains a high percentage of carbon making it very strong and hard. This property makes it suitable for any tough work. It shows high tensile strength and yield strength. Its mechanical properties are the reason behind its high demand in sectors like car manufacturing and aeroplane-building.

 

Tensile strength

515 MPa

Yield strength (@strain 0.200%)

240 MPa

Elastic modulus

193 GPa

Poisson’s ratio

0.27-0.30

Elongation at break (in 50 mm)

55.00%

Hardness, Brinell (converted from Rockwell B hardness)

123

Hardness, Knoop (converted from Rockwell B hardness)

138

Hardness, Rockwell B

70

Hardness, Vickers (converted from Rockwell B hardness)

129

Thermal Properties of Grade 384 Stainless Steel

While we have already discussed the mechanical and physical properties of the stainless steel grade 384, let us now look at its thermal properties.

 

Thermal expansion co-efficient (@0-100°C/32-212°F)

17.3 µm/m°C

Thermal conductivity (@100°C/212°F)

16.3 W/mK

 

Applications of Grade 384 Stainless Steel

Grade 384 stainless steel because of its magnificent properties is widely used in various applications including:

  • cutlery, 
  • surgical instruments, 
  • general hardware,
  • valve and pump shafts and, 
  • parts of the machines,
  • heavy machinery,
  • turbine blades,
  • steam turbine,
  • In several applications having high temperatures.