Time:2011年04月13日 人氣: 來源:本站原創(chuàng)
1, duplex stainless steel Features: duplex stainless steel is a solid solution in the ferrite organization similar to each half of the austenitic phase, the phase of the general content of less need to reach 30%. In the case with the lower C, Cr content 18% ~ 28%, Ni content of 3% to 10%. Some steel also contains Mo, Cu, Nb, ti, N and other alloying elements. Both austenitic class steel and ferritic stainless steel features, compared with the ferrite, plastic, higher toughness, no room temperature brittle, intergranular corrosion resistance and welding properties were significantly improved, while maintaining iron 475 ℃ ferritic stainless steel brittle and high thermal conductivity, with superplastic characteristics. Compared with the austenitic stainless steel, high strength and resistance to intergranular corrosion and stress corrosion compounds significantly improved. Duplex stainless steel has excellent resistance to pitting corrosion.
2, I started the company since the nineties of last century, the production of duplex stainless steel, the company has its own foundry, you can control the entire process of production, bundle CD-4MCu 2025, to 2205, until recent years widely used in 2507, my company in the years of production, and explore the many unique experiences to ensure the qualified products used in various fields. Especially for high chloride content of the transmission medium, the sea transport. The success of APL and other power companies in India 2507 produced water circulation pump, high chloride ion in the Indian region (containing up to 20000mg / l) of water and long-term use.
3, commonly used indicators of physical and chemical properties of duplex stainless steel (ASTM A790/790M-02):
Steel | C≤ | Mn≤ | Si≤ | S≤ | P≤ | Cr | Ni | Mo | Cu≤ | N |
S32750(SAF2507) | 0.03 | 1.20 | 0.80 | 0.020 | 0.035 | 24.0/26.0 | 6.0/8.0 | 3.0/5.0 | 0.50 | 0.24/0.32 |
S31803(SAF2205) | 0.03 | 2.00 | 1.0 | 0.02 | 0.030 | 21.0/23.0 | 4.50/6.50 | 2.50/3.50 | 0.08/0.20 | |
S31500(3RE60)00C | 0.03 | 1.2/2.00 | 1.4/2.00 | 0.030 | 0.030 | 18.0/19.0 | 4.25/5.25 | 2.50/3.00 | 0.05/0.10 |
2) Mechanical Properties
Project / Steel | ℃ heat treatment | σb (Mpa) | σs(Mpa) | δ% | Hardness≤ | ||
Brinell | Rockwell | ||||||
S32750(SAF2507) | 1025-1125 | 800 | 550 | 15 | 310 | 32 | |
S31803(SAF2205) | 1020-1100 | 620 | 450 | 25 | 290 | 30.5 | |
S31500(3RE60) | 980-1040 | 630 | 440 | 30 | 290 | 30.5 |
4, duplex stainless steel smelting process:
1) The medium frequency electric furnace, strict control of steel temperature.
2) The ratio of strictly material, the chemical composition of duplex stainless steel strict control, especially nitrogen directly determines the content of the performance of dual phase steel, the company uses a unique technology, strict to ensure that the content of nitrogen.
3) According to the characteristics of duplex stainless steel components, the strict implementation of heat treatment.
5, duplex stainless steel heat treatment requirements:
Duplex Stainless Steel Heat Treatment: The solution treatment.
6, duplex stainless steel machining process:
According to different requirements of the part, I have developed for each part of the strict process to ensure that the processing of qualified parts.
7, the duplex stainless steel of the test:
1) The chemical composition test.
2) The microstructure examination.
3) mechanical properties.