Biphase Stainless Steel
High Temperature Alloy
◆F51 (31803) is the most widely used duplex stainless steel, mainly used in sour oil and gas well production, in oil refining, chemical, fertilizer, petrochemical and other fields, for the manufacture of heat exchangers, condensing coolers, etc., which are prone to pitting corrosion and stress corrosion of pressure equipment. Instead of 304L, 316L austenitic stainless steel.
◆F53 (S32750) is a super duplex stainless steel with nitrogen added, which is mainly used in chemical, petrochemical and marine equipment that require special strength and corrosion resistance.
◆F55 (S32760) is a super duplex stainless steel with high strength, high resistance to chloride localized corrosion and stress corrosion, and weldable.
◆329 (S32900) has good oxidation resistance, corrosion resistance, high strength, and is suitable for environments such as seawater corrosion resistance.
◆A4 steel (0Cr17Mn13Mo2N) is a dual-phase steel, and its corrosion resistance is better than that of commonly used austenitic steel with Mo content of 2%-3%. It can be applied to small chemical fertilizers, full cycle urea equipment, etc.
◆S31050 has high resistance to chloride stress corrosion cracking, excellent resistance to pitting corrosion and crevice corrosion.
◆U3 has anti-scouring and anti-corrosion properties, and is often used to make valve cores, valve seats and other internal valve components.
◆HD is widely used in electronic industry, photoelectric industry, petrochemical industry, automobile industry and other speed-regulating electric oil well pumps.
◆C4 is suitable for large-scale vertical mixers, mixers, mixers, horizontal mixers and other machinery industries.
◆DS-2 has corrosion resistance in high temperature concentrated sulfuric acid, and is suitable for machinery industry in high temperature concentrated sulfuric acid industry.
Chemical composition
Grade |
C |
Si |
Mn |
S |
P |
Cr |
Ni |
Mo |
Cu |
N |
W |
other |
no greater than |
||||||||||||
F51 |
0.03 |
1 |
2 |
0.02 |
0.03 |
21~23 |
4.5~6.5 |
2.5~3.5 |
- |
0.08~0.2 |
- |
- |
F53 |
0.03 |
0.8 |
1.2 |
0.02 |
0.035 |
24~26 |
6~8 |
3~5 |
≤0.5 |
0.24~0.32 |
— |
- |
F55 |
0.03 |
1 |
1 |
0.01 |
0.03 |
24~26 |
6~8 |
3~4 |
0.5~1 |
0.2~0.3 |
0.5~1 |
- |
329 |
0.08 |
1 |
1.5 |
0.03 |
0.035 |
23~28 |
3~6 |
1~3 |
- |
- |
- |
- |
A4 steel |
0.08 |
0.7 |
12~15 |
0.02 |
0.045 |
16.5~18.5 |
- |
1.8~2.2 |
- |
0.2~0.3 |
- |
- |
S31050 |
0.02 |
0.7 |
2 |
0.01 |
0.025 |
24~26 |
21~23 |
2~2.5 |
— |
0.1~0.16 |
— |
- |
U3 |
0.02 |
0.4 |
2.5~3 |
0.015 |
0.02 |
24~26 |
19~21 |
2.5~3 |
— |
0.2~0.3 |
- |
- |
HD |
0.03 |
4.5~6 |
1 |
0.01 |
0.03 |
17~19 |
18~20 |
0.3~0.8 |
1.5~2.5 |
- |
- |
- |
C4 |
0.03 |
3~4.5 |
1 |
0.025 |
0.03 |
13~15 |
13~15 |
- |
- |
- |
- |
- |
DS-2 |
0.02 |
5~7 |
1 |
0.03 |
0.03 |
8~11 |
22~25 |
- |
- |
- |
- |
- |
Alloy property minimum
state |
tensile strength RmN/m㎡ |
Yield Strength Rp0.2N/m㎡ |
Elongation As% |
Brinell hardness HB |
|
F51 |
Solution treatment |
620 |
450 |
25 |
290 |
F53 |
Solution treatment |
800 |
550 |
15 |
310 |
F55 |
Solution treatment |
820 |
550 |
25 |
- |
329 |
Solution treatment |
620 |
485 |
20 |
271 |
A4 steel |
Solution treatment |
480 |
255 |
25 |
- |
S31050 |
Solution treatment |
650 |
380 |
24 |
- |
U3 |
Solution treatment |
680 |
400 |
22 |
- |
HD |
Solution treatment |
750 |
410 |
25 |
- |
C4 |
Solution treatment |
800 |
400 |
23 |
- |
DS-2 |
Solution treatment |
690 |
390 |
21 |
- |