Types of stainless steel
2021-11-24 10:57
Types of stainless steel
Stainless steel can be broadly classified by use, chemical composition and metallographic organization. The austenitic system of steel consists of 18% chromium - 8% nickel as the basic composition, the amount of each element added varies, and the development of various uses of steel.
Classified by chemical composition.
CR series: Ferritic series, Martensitic series
CR-NI series: Austenitic series, abnormal series, precipitation hardening series.
Classified by metallographic organization.
Austenitic stainless steel, ferritic stainless steel, martensitic stainless steel, duplex stainless steel, precipitation hardening stainless steel
Steel classification methods
1. Classified by chemical composition.
◆ carbon steel ◆ alloy steel: low alloy steel: alloying elements ≤ 5% high alloy steel: alloying elements ≥ 10% medium alloy steel: alloying elements 5% -10%
Note: Stainless steel is high-alloy steel.
2. Classification by quality.
① ordinary steel ② quality steel ③ senior quality (A) ④ special quality steel (E)
3. Classified by smelting method.
◆ Blast furnace steel ◆ Converter steel ◆ Electric furnace steel
4. Classified by application.
① C plain structural steel such as: 45# ② Alloy structural steel such as: 40Cr ③ C plain tool steel such as: T8 ④ Alloy tool steel such as: 3Cr2W8V ⑤ Spring steel such as: 60Si2Mn ⑥ Bearing steel such as: GCr15 ⑦ Stainless steel heat-resistant steel ⑧ High-speed steel such as: W18Cr4V
5. According to the classification of metallographic organization.
① According to the annealing state:
◆ Sub-eutectoid steel ◆ Eutectoid steel ◆ Over-eutectoid steel ◆ Leydenite steel
② According to the annealing state: Stainless steel as an example
◆ Austenitic: 0Cr18Ni9 (304) also known as: 18-8 ◆ Martensitic: 1Cr13 2 2Cr13 3Cr13 also known as: Cr13 ◆ Ferritic: 1Cr17 Cr25Ti ◆ Duplex stainless steel (ferrite, austenitic duplex): such as: 3RE60 ◆ Sink pad solid solution hardening stainless steel: 0Cr17Ni7A1 for the missile nuclear industry
