Stainless steel roll steel classification table
Material type
Chinese brand (GB)
American grade (AISI/SAE)
European Brand (EN)
Main characteristics
Typical use
Austenitic stainless steel
06Cr19Ni10 (304)
304
1.4301
Corrosion-resistant, non-magnetic, easy to process
Food equipment, building decoration, elevator board
06Cr17Ni12Mo2 (316)
316
1.4401
Acid and alkali resistance (including Mo), pitting resistance
Chemical industry, Marine environment, medical equipment
022Cr17Ni12Mo2 (316L)
316L
1.4404
Ultra-low carbon, resistance to intergranular corrosion after welding
Nuclear power, oil pipelines
Ferrite stainless steel
10Cr17 (430)
430
1.4016
Magnetic, oxidation resistant, low cost
Home appliance shell, kitchenware, automobile exhaust pipe
022Cr18Ti (439)
439
1.4510
High temperature oxidation resistance, good weldability
Automobile exhaust system, water heater liner
Martensitic stainless steel
12Cr13 (410)
410
1.4006
High strength, heat treatment, wear resistance
Tools, bearings, mechanical parts
20Cr13 (420)
420
1.4021
High hardness, good polishing
Surgical instruments, tableware
Duplex stainless steel
022Cr23Ni5Mo3N (2205)
2205
1.4462
High strength + high corrosion resistance (austenite + ferrite mix)
Chemical storage tank, seawater treatment equipment
022Cr25Ni7Mo4N (2507)
2507
1.4410
Super duplex steel, resistant to chloride corrosion
Oil platform, desalination equipment
Precipitation hardened stainless steel
07Cr17Ni7Al (631)
17-4PH
1.4542
Can be strengthened by heat treatment, high strength
Aerospace, precision instrument parts
Stainless steel roll steel classification table
Surface treatment type
Code/name
Process specification
peculiarity
Typical use
Cold-rolled surface
2B (Cold rolled bright finish)
After cold rolling, it is annealed, pickling, and finally rolled lightly with a flat roll
Smooth reflective, light matte, most commonly used
Architectural decoration, home appliances, elevator panels
BA (Bright annealing)
Annealing in hydrogen or vacuum environment to retain the high gloss after rolling
High reflectivity, no oxide skin, close to mirror
High-end electrical appliances, mirror substrates
No.1 (Hot rolling, annealing and pickling)
Hot rolling backfire and pickling to remove the oxide layer
Rough and dull, low cost
Industrial structural parts, chemical equipment
Mechanical polishing
No.3 (Rough sanding)
Polishing with 100~120 mesh grinding material
Visible uniform abrasion, semi-matte finish
Kitchen equipment, industrial parts
No.4 (Drawing)
One-way polishing with 150~180 mesh grinding belt
Fine stripes, anti-fingerprint, commonly used
Elevator interior, home appliance panel
HL (Scrub)
Cross polishing to form a non-directional texture
Matte, wear resistant, hidden scratches
Building exterior walls, rail transit
Mirror finish
6K (Ordinary mirror)
First polishing with coarse abrasive, and then fine abrasive (such as diamond plaster) polishing
high reflectivity, but there may be fine lines
Decorative decoration, luxury display cases
8K (Super mirror)
Multi-pass precision polishing to flawless
Close to glass mirror effect
High-end hotels, art installations
Special treatment
Embossed
By rolling out three-dimensional patterns (such as diamond, leather pattern)
decorative strong, non-slip
Decoration, furniture, ship interior
Color coating (PVD/ electroplating)
Vacuum ion coating or electroplating coloring (titanium, rose gold, etc.)
corrosion resistance, rich color
Luxury goods, iconic buildings
Sandblasting
High speed spray sand particles to form a uniform rough surface
Matte texture, anti-glare
Industrial equipment, outdoor facilities
Etching
Chemical or laser etching of patterns/text
Customized pattern, permanent retention
Brand identity, artistic creation
Functional processing
AFCoating
Nanometer coating reduces fingerprint residue
Easy to clean and keep beautiful
Electronic devices, high frequency touch areas
Passivation
Nitric or citric acid treatment enhances the oxide film
Improved corrosion resistance
Medical equipment, food industry
Stainless steel production process
1. Prepare raw materials
Main raw materials:
Iron ore or steel scrap (recycled)
Alloying elements: Chromium (Cr, ≥10.5%), nickel (Ni), molybdenum (Mo), manganese (Mn), etc
Flux: limestone (CaO), fluorite (CaF₂), etc. (for desulfurization, dephosphorization)
2. Smelting process
Stainless steel smelting usually adopts the "three-step method" (blast furnace/electric furnace → AOD/VOD refining → continuous casting) :
Primary refining (EAF or converter) :
Electric arc Furnace (EAF) : Melting scrap steel and alloys, suitable for small batch, high alloy steel (e.g. 316L).
Converter: For mass production (e.g. 304), the cost is lower.
Refining (key step) :
AOD (argon-oxygen decarburization) : By blowing into argon-oxygen mixture gas to reduce carbon content, while reducing chromium oxidation (suitable for 300 series austenitic steel).
VOD (Vacuum oxygen decarbonization) : Decarbonized in a vacuum environment, suitable for ultra-low carbon stainless steel (such as 316L).
Continuous Casting:
Molten steel is cast into slab, square or round billet (thickness 150~250mm).
3. Hot rolling
Heating furnace: slab heating to 1100~1250℃.
Roughing + finishing rolling: the slab is rolled into hot rolled coil (thickness 2~10mm) through multiple rolling.
Pickling: Remove the surface oxide (nitric acid + hydrofluoric acid mixture).
4. Cold rolling (precision thickness control)
Cold rolling machine: rolling at room temperature, the thickness can be reduced to 0.3~3mm, the surface is smoother.
Annealing: removal of work hardening (protection of atmosphere against oxidation).
Second pickling: Ensure clean surface.
5. Surface treatment
2B surface: cold rolling + annealing + pickling + light rolling (most commonly used).
BA mirror: bright annealed, no oxidation.
No.4 Wire drawing /HL scrub: Mechanical polishing or sandblasting.
6. Finished product processing
Stripe: Cut into different widths according to customer requirements.
Cutting/stamping: making plates, pipes, parts, etc.
