I. First Understand the Core: Basic Cognition of Stainless Steel Plates (Avoid Being Misled by Terminology)
Stainless steel plates are made of stainless steel as the base material through rolling, shearing, surface treatment and other processes. Their core advantage is "stainless" — derived from the dense Cr₂O₃ passivation film formed on the surface, which can resist corrosion from the atmosphere, moisture, acids and alkalis and other media. Before purchasing, clarify 3 core concepts to avoid being misled by merchants:
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Substrate Classification: According to the metallographic structure, it can be divided into 4 categories (mainstream on the market, focus on mastering). The core differences are reflected in corrosion resistance, strength, processability and cost, which are the core basis for subsequent selection;
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Specification Parameters: Thickness, width and length are the foundation. Details such as surface finish, tolerance and hardness directly affect the use effect and processing cost;
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Surface Treatment: Different surface processes are suitable for different scenarios, balancing appearance and practicality, avoiding blind pursuit of "high gloss" while ignoring adaptability.
Key Reminder: The "stainless" of stainless steel plates is not absolute. If the material does not match the service environment, rust, cracking and other problems will still occur. Choosing the right material is more important than choosing the brand.
II. Detailed Explanation of Core Parameters: Every Item Affects Use, Don’t Ignore!
The parameters of stainless steel plates directly determine their performance and applicable scenarios. The following are the parameters that must be focused on when purchasing, with detailed explanations and selection suggestions, refusing to pile up invalid parameters:
(I) Basic Specification Parameters (Must-See to Avoid Size Mismatch)
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Parameter Name
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Core Explanation
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Common Specifications
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Selection Suggestions
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Thickness (mm)
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Determines the load-bearing capacity, impact resistance and processing difficulty of the plate. Thickness tolerance must be focused on (to avoid cutting corners)
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0.3-100mm (commonly used 0.5-10mm)
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Thin plates (0.3-1.2mm): Decoration, home appliance casings; Medium and thick plates (1.5-10mm): Equipment casings, countertops; Thick plates (≥12mm): Industrial load-bearing, mechanical structures
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Width (mm)
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The conventional width on the market is fixed, and special widths need to be customized, which affects construction efficiency and material utilization rate
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1000, 1220, 1500, 2000 (mainstream)
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Household/small-scale decoration: 1000-1220mm; Large-scale engineering/industry: 1500-2000mm (reduce splicing and loss)
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Length (mm)
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The conventional length is matched with the width, which can be cut on demand. The cutting accuracy affects subsequent processing
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2000, 2440, 3000, 6000
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Cut on demand, focusing on requiring no burrs or deformation on the cutting surface (especially for precision processing scenarios)
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Thickness Tolerance
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There are clear national standards. Excessive deviation is likely to lead to processing failure (such as bending cracking, stamping deformation)
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Conventional tolerance ±0.01-0.05mm (thin plates), ±0.1-0.3mm (thick plates)
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Precision processing (such as kitchenware, medical equipment): Select tolerance ≤±0.02mm; Ordinary scenarios: Within ±0.1mm, be sure to write it into the contract
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(II) Core Material Parameters (Determine Corrosion Resistance, Top Priority)
The corrosion resistance, strength and processability of stainless steel plates are mainly determined by chemical composition. The differences in element ratio of different materials directly lead to great differences in applicable scenarios. Focus on the following core elements and parameters:
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Chromium (Cr): The core anti-rust element. Only when the content is ≥10.5% can it be called stainless steel. The higher the content, the stronger the basic corrosion resistance (for example, 304 contains 18-20% Cr, 316 contains 16-18% Cr);
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Nickel (Ni): Improves the toughness, ductility and corrosion resistance of the plate. The higher the nickel content, the more stable the material (304 contains 8-10.5% Ni, 316 contains 10-14% Ni), which is also the core element affecting the price;
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Molybdenum (Mo): Improves the resistance to chloride ion corrosion, which is the key to dealing with seawater, chlorine-containing chemical media (316 series contains 2-3% Mo, 304 does not contain Mo);
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Carbon (C): Affects the hardness and welding performance of the plate. Low-carbon versions (such as 304L, 316L, C≤0.03%) can avoid intergranular corrosion after welding, which is suitable for welding scenarios;
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Other Elements: Titanium (Ti) improves high temperature resistance (such as 321), Nitrogen (N) improves strength (such as duplex steel 2205), select on demand.
(III) Surface Quality Parameters (Balance Appearance and Practicality)
The surface treatment of stainless steel plates not only affects the appearance, but also affects the corrosion resistance and cleaning difficulty. The common surface grades and parameters are as follows (sorted from low to high finish):
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Surface Grade
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Surface State
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Core Parameters
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Applicable Scenarios
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2B (Cold Rolled)
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Matte, flat, no obvious luster on the surface, delicate hand feel
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Roughness Ra≤0.4μm, no scratches, no sand holes
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Home appliance casings, equipment linings, indoor decoration (highest cost performance, most commonly used)
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BA (Cold Rolled)
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Mirror luster, high reflectivity, smooth as a mirror on the surface
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Roughness Ra≤0.15μm, no any defects
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High-end decoration, kitchenware, medical equipment, mirror curtain walls
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NO.1 (Hot Rolled)
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Matte, with rolling texture on the surface, slightly poor flatness
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Roughness Ra≤1.6μm, slight oxide color is acceptable
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Industrial load-bearing, mechanical processing, large-scale equipment bases (no pursuit of appearance)
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Brushed (HL)
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Brushed texture, matte, fingerprint-proof, easy to clean
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Uniform texture, no broken wires, no color difference
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Kitchen and bathroom countertops, elevator panels, decorative panels (preferred for household/commercial use)
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(IV) Mechanical Performance Parameters (Adapt to Processing and Load-Bearing Needs)
For scenarios requiring bending, stamping, welding and load-bearing, mechanical parameters must be paid attention to to avoid processing failure or damage during use. The core parameters are as follows:
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Hardness (HV): Affects processing difficulty. The lower the hardness, the easier it is to bend and stamp; The conventional hardness of 304/316 is HV160-180, select ≤HV150 for stamping scenarios, and ≥HV200 for wear-resistant scenarios;
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Yield Strength (MPa): Key for load-bearing scenarios. The higher the yield strength, the stronger the deformation resistance (the yield strength of 304/316 is 205-310MPa, and that of duplex steel can reach more than 400MPa);
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Elongation (%): Affects ductility. The higher the elongation, the easier it is to stretch and form (the elongation of 304/316 is ≥50%, suitable for deep drawing processing);
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Welding Performance: Low-carbon materials (304L, 316L) have better welding performance, no intergranular corrosion risk, and are suitable for large-scale welded structural parts.
III. Detailed Explanation of Mainstream Stainless Steel Plate Materials on the Market (With Comparison, Accurate Selection)
There are many types of stainless steel plate materials on the market. Focus on 4 categories and 8 mainstream models, covering more than 90% of the use scenarios, avoiding blind pursuit of high-end materials (wasting costs) or low-end materials (short service life). The following are detailed parameters, characteristics and applications, with an intuitive comparison table:
(I) Core Characteristics of Four Categories of Materials (Distinguish at a Glance)
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Austenitic Stainless Steel: Non-magnetic, excellent corrosion resistance, good processability, cannot be strengthened by heat treatment, and is the most commonly used category (representatives: 304, 316 series);
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Ferritic Stainless Steel: Magnetic, nickel-free, low cost, good high temperature resistance, poor ductility and welding performance (representatives: 430, 409L);
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Martensitic Stainless Steel: Magnetic, high carbon content, can be strengthened by heat treatment, high strength, high hardness, poor corrosion resistance (representatives: 410, 440C);
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Duplex Stainless Steel: Weakly magnetic, combining the advantages of austenitic and ferritic, high strength + high corrosion resistance, suitable for harsh environments (representatives: 2205, 2507).
(II) Detailed Explanation of Mainstream Models (Focus on Mastering)
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Material Model
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National Standard Brand
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Core Chemical Composition (Key)
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Core Characteristics
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Applicable Scenarios
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Reference Price (RMB/㎡, March 2026)
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06Cr19Ni10
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Cr18-20%, Ni8-10.5%, C≤0.08%, no Mo
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Universal "all-rounder", corrosion resistant to atmosphere, fresh water and dilute nitric acid, excellent processability, moderate cost, non-magnetic; Disadvantage: Weak resistance to chloride ion corrosion, general performance at high temperature (>600℃)
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Indoor decoration, home appliance casings, kitchenware, fresh water pipes, ordinary equipment brackets, food processing equipment (non-high salt environment)
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180-280 (floating according to thickness and surface grade)
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022Cr19Ni10
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Cr18-20%, Ni8-10.5%, C≤0.03%, no Mo
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Low-carbon version of 304, solves the problem of intergranular corrosion after welding, slightly better corrosion resistance than 304, consistent processability, slightly lower strength
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Large-scale welded structural parts, chemical equipment frames, architectural welded pipes, welding parts of food processing production lines
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200-300
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06Cr17Ni12Mo2
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Cr16-18%, Ni10-14%, Mo2-3%, C≤0.08%
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Corrosion-resistant upgraded version, strong resistance to chloride ion, seawater, acid and alkali corrosion, high temperature resistant (≤800℃), non-magnetic; Disadvantage: Cost is 20-30% higher than 304
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Coastal buildings, marine engineering, chemical equipment, humid and corrosive environments, outdoor decoration (seaside)
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240-380
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022Cr17Ni12Mo2
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Cr16-18%, Ni10-14%, Mo2-3%, C≤0.03%
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Low-carbon version of 316, no intergranular corrosion after welding, optimal corrosion resistance, suitable for high-end welding scenarios
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Pharmaceutical equipment, medical equipment, deep-sea equipment, high-end chemical equipment, semiconductor factories
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260-400
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06Cr18Ni11Ti
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Cr18-20%, Ni10-12%, Ti0.3-0.8%, no Mo
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High-temperature special version, added titanium element, strong resistance to intergranular corrosion, high temperature resistant (≤850℃), good welding performance
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Boiler heating surfaces, heat exchangers, high-temperature pipes, automobile exhaust systems, aerospace auxiliary structures
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280-420
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10Cr17
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Cr16-18%, no Ni, C≤0.12%
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Basic low-cost version, magnetic, good atmospheric corrosion resistance, general processability, poor welding performance, cost is only half of 304
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Home appliance casings, indoor low-corrosion decoration, water heater liners, non-load-bearing panels
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90-150
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12Cr13
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Cr11.5-13.5%, no Ni, C0.12-0.17%
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Basic high-strength version, magnetic, can be strengthened by heat treatment, high hardness (above HRC40), general corrosion resistance
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Mechanical tools, valves, pump bodies, agricultural machinery accessories, load-bearing parts in low-corrosion environments
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120-200
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022Cr22Ni5Mo3N
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Cr21-23%, Ni4.5-6.5%, Mo2.5-3.5%, N0.14-0.20%
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Excellent comprehensive performance, weakly magnetic, strength is twice that of 304, better resistance to chloride ion corrosion than 316L, good welding performance
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Marine engineering, hydrometallurgy, papermaking equipment, oil and gas extraction equipment, harsh corrosive environments
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500-700
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(III) Core Comparison of Mainstream Materials (Quick Selection, Avoid Pitfalls)
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Comparison Dimension
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304/304L
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316/316L
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430
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2205 Duplex Steel
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Corrosion Resistance
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Medium (not resistant to chloride ions)
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Excellent (resistant to chloride ions, seawater)
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General (only resistant to atmospheric corrosion)
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Excellent (suitable for harsh corrosive environments)
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Processability
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Excellent (easy to bend, stamp, weld)
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Good (special welding wire required for welding)
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General (easy to embrittle during welding)
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Good (processing difficulty is slightly higher than 304)
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Strength
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Medium
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Medium
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Low
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Very High (twice that of 304)
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Magnetism
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None
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None
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Yes
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Weak
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Cost
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Medium (highest cost performance)
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High (20-30% higher than 304)
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Low (only half of 304)
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High (for high-end industrial use only)
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Applicable Scenarios
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Universal scenarios (indoor, non-corrosive)
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Corrosive scenarios (seaside, chemical industry)
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Low-cost, low-requirement scenarios
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Harsh environments (deep sea, strong corrosion)
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IV. Scenario-Based Shopping Guide: Choose According to Purpose, One Step in Place (Core Focus)
The core logic of choosing stainless steel plates: Scenarios determine materials, and materials determine parameters. There is no need to blindly pursue high-end materials. Matching scenarios is the most cost-effective choice. The following are accurate selection suggestions for common scenarios, covering more than 90% of needs:
(I) Architectural Decoration Scenarios
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Indoor Decoration (Ceilings, Walls, Handrails): Priority is given to 304 stainless steel plates (2B/brushed surface), thickness 0.8-1.2mm, high cost performance, high appearance, and more beautiful without magnetism; If the budget is limited, 430 stainless steel plates can be selected (only for indoor dry environments);
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Outdoor Decoration (Curtain Walls, Guardrails, Signs): Choose according to the environment — 304 (brushed surface, fingerprint-proof) for inland areas, thickness 1.2-2.0mm; 316 (seawater corrosion resistant) must be selected for coastal areas, thickness 1.5-2.5mm;
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High-End Decoration (Hotel, Mall Mirror Curtain Walls): Choose 304/316 BA mirror stainless steel plates, thickness 1.0-1.5mm, no defects on the surface, high reflectivity, and improve the overall texture.
(II) Kitchen and Bathroom Appliance Scenarios
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Kitchen (Countertops, Sinks, Kitchenware): Priority is given to 304 brushed stainless steel plates (thickness 1.0-1.5mm), fingerprint-proof, easy to clean, and meets food-grade standards; If often in contact with salt water (such as seafood processing), choose 316 brushed plates to avoid rust;
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Bathroom (Countertops, Walls): Choose 304/316 2B/brushed plates, thickness 0.8-1.2mm, moisture-proof and corrosion-resistant, avoid choosing 430 (easy to rust);
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Home Appliance Casings (Refrigerators, Washing Machines, Water Heaters): 304 2B plates (thickness 0.5-0.8mm), high cost performance and easy processing; Water heater liners choose 430 or 304, high temperature resistant and corrosion resistant.
(III) Industrial Manufacturing Scenarios
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Ordinary Equipment (Casings, Brackets, Pipes): 304 stainless steel plates (thickness 1.5-5.0mm), atmospheric corrosion resistant, good processability, meeting conventional industrial needs; For structural parts requiring welding, choose 304L;
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Chemical Equipment (Reactors, Pipes, Storage Tanks): In contact with chlorine-containing, acid and alkali media, choose 316/316L (thickness 3.0-10.0mm); For harsh corrosive environments (such as hydrometallurgy), choose 2205 duplex steel;
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High-Temperature Equipment (Boilers, Heat Exchangers): Choose 321 stainless steel plates (thickness 2.0-8.0mm), high temperature resistant, strong resistance to intergranular corrosion, suitable for high-temperature scenarios above 600℃;
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Wear-Resistant Components (Tools, Valves, Bearings): Choose 410/440C martensitic stainless steel plates, which can be strengthened by heat treatment, high hardness, high wear resistance, thickness 2.0-5.0mm.
(IV) Food and Medical Scenarios
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Food Processing (Equipment, Countertops, Conveyor Pipes): Must choose food-grade 304/316 stainless steel plates (2B surface), thickness 1.0-2.0mm, no burrs, no sand holes, easy to clean, no peculiar smell, meeting food-grade testing standards;
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Medical Equipment (Surgical Instruments, Sterilization Equipment): Choose 316L stainless steel plates (BA surface), thickness 0.8-1.5mm, strong corrosion resistance, can withstand high-temperature sterilization, no heavy metal precipitation, meeting medical-grade standards.
V. Pitfall Avoidance Skills for Purchasing (Top Priority, Refuse to Be Tricked)
The stainless steel plates on the market are mixed, and many merchants pass off inferior products as high-quality ones (such as 201 passing off as 304, 304 passing off as 316). The following 6 pitfall avoidance skills help you avoid 99% of the traps, especially suitable for beginners:
1. Refuse "Low-Price Temptation", You Get What You Pay For
The price of stainless steel plates is determined by material, thickness and surface grade. Those lower than the market average are likely to be inferior plates: for example, 304 plates lower than 180 yuan/㎡ (1.0mm thick) may be 201 passing off (201 has high manganese content, easy to rust, and the cost is only half of 304); 316 plates lower than 240 yuan/㎡ may be 304 passing off, no molybdenum element, poor corrosion resistance.
2. Request Material Certification and Test Report
Regular merchants will provide material certificates (marking chemical composition and mechanical properties) and spectral test reports. Focus on checking the contents of Ni, Cr and Mo: 304 requires Ni≥8%, Cr≥18%; 316 requires Ni≥10%, Cr≥16%, Mo≥2%. Identify authenticity in three seconds: log in to the "National Iron and Steel Materials Testing Center" applet, enter the report number, check that the furnace batch number is consistent with the steel coil spray code, and be alert to secondary printing if the test date exceeds 30 days.
3. On-Site Material Testing (Simple and Easy to Operate)
No professional equipment is needed, 2 simple methods for quick identification:
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Magnet Test: 304/316 are non-magnetic (slight magnetism is normal, caused by cold processing), 430/410 have strong magnetism, 201 has weak magnetism;
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Reagent Test: Buy stainless steel test reagent online, drop it on the plate, 304 does not change color, 316 turns light red, 201 turns dark red (simple and efficient, suitable for on-site testing);
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Grain Size Test: Carry 10% oxalic acid electrolytic corrosion solution with you, energize for 5 seconds, grain boundaries can be seen under a microscope, and 6-7 grade grain size is most suitable for processing and forming.
4. Check Thickness and Tolerance to Avoid Cutting Corners
Many merchants mark 1.0mm thick, but actually only 0.8mm, which is easy to deform and crack during subsequent processing. When purchasing, measure the thickness with a caliper, the deviation must be within the national standard (±0.02mm for thin plates, ±0.1mm for thick plates), and write the tolerance requirements into the contract. Before batch purchase, require the supplier to provide the same coil difference test (the thickness difference between the three points of the head, middle and tail of the same steel coil ≤0.008mm).
5. Check Surface Quality to Avoid Defects
High-quality stainless steel plates should be flat, free of scratches, sand holes and color differences, with uniform brushed texture and no defects on the mirror surface. If there are obvious defects on the surface, it will not only affect the appearance, but also reduce the corrosion resistance (defects are easy to rust). At the same time, pay attention to the surface roughness. For precision processing scenarios, Ra≤0.2μm is required, and the Rz/Ra ratio ≤6 to reduce processing tool wear.
6. Clarify Surface Treatment and Processing Needs
Different surface treatments have great differences in price and purpose, avoiding confusion by merchants: for example, passing off 2B surface as BA surface (price difference 50-100 yuan/㎡); For scenarios requiring bending and stamping, inform the merchant in advance, select plates with moderate hardness (HV160-180) and high elongation to avoid processing cracking. For welding scenarios, select low-carbon materials (304L, 316L), and require the merchant to provide welding process suggestions to reduce the risk of intergranular corrosion after welding.
VI. Frequently Asked Questions (FAQ): Solve Your Last Doubts
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Q: Which one should I choose between 304 and 316? A: It depends on whether it is in contact with chloride ions (seawater, salt water, chlorine-containing chemical media). If it is in contact, choose 316; If not (indoor, fresh water environment), choose 304, which is more cost-effective. If the budget is sufficient and long-term durability is pursued, you can directly choose 316.
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Q: Will stainless steel plates rust? A: Yes! If the material does not match the scenario (such as 304 used by the seaside), the surface has scratches (damaging the passivation film), or it is in contact with strong corrosive media, it will rust. Regular cleaning and avoiding scratches can extend the service life.
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Q: Is the thicker the better? A: No! The thickness needs to match the purpose. For example, 0.8-1.2mm is enough for decoration scenarios, and too thick will increase the cost; For load-bearing and industrial scenarios, thick plates (≥3.0mm) must be selected to ensure strength.
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Q: What are the requirements for food-grade stainless steel plates? A: It must be 304/316 material, with no burrs or sand holes on the surface, meeting the GB 4806.9-2016 standard, no heavy metal precipitation, and can provide food-grade test reports.
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Q: How to reduce the purchase cost of stainless steel plates? A: 1. Choose materials on demand, do not blindly pursue 316/duplex steel; 2. Choose conventional specifications (1220×2440mm) to avoid customization (increasing cost); 3. Purchase in bulk and negotiate with merchants for a better price; 4. Reasonably choose the surface grade, and there is no need to choose BA surface for non-high-end scenarios.
VII. Summary: Core Selection Rhyme (Remember to Avoid Pitfalls)
Scenarios determine materials, parameters depend on needs, price distinguishes advantages and disadvantages, certificates prevent fraud; Choose 304 for indoor, 316 for seaside, 321 for high temperature, 410 for wear resistance, and duplex steel for harsh conditions; Thickness depends on purpose, surface depends on appearance, tolerance depends on details, and testing depends on reports.
I hope this complete guide to stainless steel plate selection can help you solve all your questions in purchasing and accurately select the stainless steel plate suitable for you. If there are specific scenarios (such as specific industrial uses, budget scope), you can leave a message for consultation, and I will help you further refine the selection plan!
