Austenitic SS 347 Flat
Stainless Steel 347 flat and Stainless Steel 347 flat or Alloy 347 (UNS S34700) is columbium stabilized austenitic stainless steel flat with good general corrosion resistance and somewhat better resistance in strong oxidizing conditions than 321 (UNS S32100). It has excellent resistance to intergranular corrosion after exposure to temperatures in the chromium carbide precipitation range of 800 – 1500°F (427 – 816°C).
Chemical Properties
|
GRADE |
Cr |
Ni |
C |
Mn |
P |
Si |
Fe |
S |
Cb) |
|
|---|---|---|---|---|---|---|---|---|---|---|
|
SS 347H |
MIN |
17 |
9 |
0.04 |
– |
– |
– |
– |
10 x (C) |
|
|
MAX |
19 |
13 |
0.1 |
2 |
0.045 |
1 |
BALANCE |
0.03 |
1 |
|
| SS 347 |
MIN |
17 |
9 |
– |
– |
– |
– |
– |
8 x (C) |
|
|
MAX |
19 |
13 |
0.08 |
2 |
0.045 |
1 |
BALANCE |
0.03 |
1 |
Properties
SS 347 flat exhibits good general corrosion resistance that is comparable to 304. It was developed for use in the chromium carbide precipitation range of 800 – 1500°F (427 – 816°C) where un-stabilized alloys such as 304 are subject to intergranular attack. Alloy 347 stainless steel flat is stabilized by the addition of columbium and tantalum.
Mechanical Properties
|
Grade |
Tensile Strength |
Yield Strength |
Elongation |
Hardness, MAX |
|
|---|---|---|---|---|---|
|
[MPA] |
[MPA] |
(% in 50mm) min |
HBW |
HRB |
|
|
SS 347 |
515 |
205 |
40 |
201 |
92 |
|
SS 347H |
515 |
205 |
40 |
201 |
92 |
Grade 347 stainless steel flat is also advantageous for high temperature service because of its good mechanical properties. Alloy 347 stainless steel offers higher creep and stress rupture properties than Alloy 304 and, particularly, Alloy 304L, which might also be considered for exposures where sensitization and intergranular corrosion are concerns.
PHYSICAL PROPERTIES
|
Grade |
Density (Kg/m3) |
Melting range |
Elastic Modulus (GPa) |
Mean Co-eff of Thermal Expansion (μm/m/°C) at 0-100°C |
Thermal Conductivity (W/m.K) at 100°C |
Specific Heat ( J/Kg.K) at 20°C |
Electric Resistivity at 20°C Ω mm2 /m |
|---|---|---|---|---|---|---|---|
|
SS 347/347H |
7.96 |
1398-1446 °C |
190-210 |
17.3 |
16.3 |
500 |
0.73 |
The alloy has good oxidation resistance and creep strength to 1500°F (816°C). It also possesses good low temperature toughness. Alloy 347 stainless steel flats and flat cannot be hardened by heat treatment, only by cold working. It can be easily welded and processed by standard shop fabrication practices.
Application
Grade 347 Stainless Steel flat have superior welding and forming capability and they are frequently utilized in heat exchangers, petroleum refineries, welded fabrication, pressure vessels, parts of aircraft engines and in power generation.
Shalco Industries is a manufacturing company of Flat in India and Global Supplier.
