Austenitic SS 321 Round Bar
Grades 321/321H is the basic austenitic 18/8 steel (Grade 304) stabilised by Titanium. Grade 321/321H is the grade of choice for applications in the temperature range of up to about 900°C, combining high strength, resistance to scaling and phase stability with resistance to subsequent aqueous corrosion.
Chemical Properties
|
GRADE |
Cr |
Ni |
C |
Mn |
P |
Si |
Ti |
Fe |
S |
N |
|
|---|---|---|---|---|---|---|---|---|---|---|---|
|
SS 321/321H |
MIN % |
17 |
9 |
– |
– |
– |
– |
5x(C+N) |
– |
– |
– |
|
MAX % |
19 |
12 |
0.08 |
2 |
0.045 |
0.75 |
0.7 |
BALANCE |
0.03 |
0.1 |
SS 321 Round Bar can be used for extended periods at elevated temperatures without compromising its corrosion resistance. Alloy 321/321H has equivalent corrosion resistance to sensitisation as the low carbon version 317L.
Properties
Grade 321/321H stainless steel Bars and plates are non-magnetic in nature, have higher hot strength, and are particularly suitable for high temperature structural applications. Alloy 321/321H stainless steel exhibits good general corrosion resistance that is comparable to SS 304. Stainless Steel 321 Round Bar offers higher creep and stress rupture properties than type SS 304.
Mechanical Properties
|
Grade |
Tensile Strength |
Yield Strength |
Elongation |
Hardness, MAX |
|---|---|---|---|---|
|
[MPA] |
[MPA] |
(% in 50mm) min |
HRB |
|
|
SS 321 |
515 |
205 |
35 |
217 |
321/321H Bars respond well to hardening by cold working. The amount of titanium content required in Stainless Steel 321/321H Bar is indicative of the product percentage of carbon. 321/321HH Bars has good welding characteristics; and post-weld annealing is not normally required to restore its excellent performance in a wide range of corrosive conditions.
Physical Properties
|
Grade |
Density (g/cm3) |
Melting Point °C |
Elastic Modulus (GPa) |
Mean Co-eff of Thermal Expansion (μm/m/°C) |
Thermal Conductivity (W/m.K) |
Specific Heat (J/Kg.K) |
Electrical Resistivity (nΩ.m) |
||
|---|---|---|---|---|---|---|---|---|---|
|
0-100°C |
0-315°C |
0-538°C |
at 100°C |
0-100°C |
|||||
|
SS 321/321H |
8 |
1400-1450 |
190-210 |
16.6 |
17.2 |
18.6 |
16.1 |
500 |
720 |
Specification
The Specification for Wrought Alloy 321 Round Bar as per astm Standard is ASTM A-276/ASME SA-276, they are categorised into different form and shape such as SS 321/321H Round Bar, Rod, Channel Bar, T-Bar, Flat Bar, Blocks, Square, bar, Triangle, Threaded, Hex (A/F), Profiles, Half Ingot, Billet, I/H Bar, etc.
When considering wrought stainless round bars, material shall be furnished in the following way such as Hot-worked, Hot-worked and Annealed, Hot-worked- Annealed and cold worked or Hot-worked-Annealed and heat treated.
Round bars depending upon their treatment and their use and application they can also be available in different surface finishes such as Black, Bright Polished, Rough Turned, NO.4 Finish, Matt Finish, BA Finish, 2B, 2D, etc.
Application
Stainless Steel 321 Round Bar are mainly used in paper and pulp handling equipment, Chemical and petrochemical processing equipment, Condensers in fossil and nuclear fueled power generation stations, Food processing equipment, Textile equipment.
