The surface of the stainless steel plate is smooth, has high plasticity, toughness and mechanical strength, and is resistant to acid, alkaline gas, solution and other media corrosion. It is an alloy steel that is not easy to rust, but it is not absolutely rust free. Stainless steel plate refers to the steel plate that is resistant to the corrosion of weak media such as atmosphere, steam and water, while the acid-resistant steel plate refers to the steel plate that is resistant to the corrosion of chemical etched media such as acid, alkali and salt. Stainless steel plate since the beginning of the 20th century, has a history of more than one century.
1. Brief introduction
Stainless steel plate is generally a general term for stainless steel plate and acid resistant steel plate. At the beginning of this century, the development of stainless steel plates laid an important material and technological foundation for the development of modern industry and technological progress. There are many types of stainless steel plates with different properties, and they have gradually formed several major categories in the development process.
According to organizational structure, it can be divided into four categories: austenitic stainless steel plate, martensitic stainless steel plate (including precipitation hardened stainless steel plate), ferritic stainless steel plate, and austenitic ferritic duplex stainless steel plate. According to the main chemical composition of steel plates or some characteristic elements in steel plates, they are classified into chromium stainless steel plates, chromium nickel stainless steel plates, chromium nickel molybdenum stainless steel plates, low-carbon stainless steel plates, high molybdenum stainless steel plates, high-purity stainless steel plates, etc. According to the performance characteristics and applications of steel plates, they are classified into nitric acid resistant stainless steel plates, sulfuric acid resistant stainless steel plates, pitting resistant stainless steel plates, stress corrosion resistant stainless steel plates, high-strength stainless steel plates, etc. According to the functional characteristics of steel plates, they are classified into low-temperature stainless steel plates, non-magnetic stainless steel plates, easy cutting stainless steel plates, and superplasticity stainless steel plates. The commonly used classification method is based on the structural characteristics and chemical composition of steel plates, as well as a combination of both. Generally divided into martensitic stainless steel plate, ferritic stainless steel plate, austenitic stainless steel plate, duplex stainless steel plate, and precipitation hardening stainless steel plate, or divided into two categories: chromium stainless steel plate and nickel stainless steel plate. Widely used, typical applications include pulp and paper equipment, heat exchangers, mechanical equipment, dyeing equipment, film processing equipment, pipelines, and external materials for buildings in coastal areas.
According to the manufacturing method, there are two types: hot-rolled and cold-rolled, including thin cold plates with a thickness of 0.5.10-885 millimeters and medium thick plates with a thickness of 4.5-100 millimeters.
It is required to withstand the corrosion of various acids such as oxalic acid, sulfuric acid iron sulfate, nitric acid, nitric acid hydrofluoric acid, sulfuric acid copper sulfate, phosphoric acid, formic acid, acetic acid, etc. It is widely used in industries such as chemical, food, pharmaceutical, papermaking, petroleum, atomic energy, as well as various components of buildings, kitchenware, tableware, vehicles, and household appliances.
In order to ensure that the mechanical properties such as yield strength, tensile strength, elongation, and hardness of various stainless steel plates meet the requirements, the steel plates must undergo heat treatment such as annealing, solution treatment, and aging treatment before delivery. 05.10 88.57.29.38 special symbols.
The corrosion resistance of stainless steel mainly depends on its alloy composition (chromium, nickel, titanium, silicon, aluminum, manganese, etc.) and internal microstructure.
According to the manufacturing method, there are two types of steel: hot-rolled and cold-rolled. According to the structural characteristics of the steel grade, it can be divided into five categories: austenitic, austenitic ferritic, ferritic, martensitic, and precipitation hardening.
Stainless steel plates have a smooth surface, high plasticity, toughness, and mechanical strength, and are resistant to corrosion from acid, alkaline gases, solutions, and other media. It is an alloy steel that is not easily rusted, but it is not absolutely rust free.
2. Performance
Corrosion resistance
Stainless steel plates have the ability to resist general corrosion similar to unstable nickel chromium alloy 304. Long term heating in the temperature range of chromium carbide may affect the performance of alloys 321 and 347 in harsh corrosive media. Mainly used for high-temperature applications, which require materials to have strong anti sensitization properties to prevent intergranular corrosion at lower temperatures.
High temperature oxidation resistance
Stainless steel plates have high temperature oxidation resistance, but the oxidation rate is affected by inherent factors such as exposure environment and product form.
Physical property
The total heat transfer coefficient of a metal depends not only on its thermal conductivity, but also on other factors. In most cases, the heat dissipation coefficient of the film layer, rust scale, and surface condition of the metal. Stainless steel can maintain a clean surface, so its heat transfer is better than other metals with higher thermal conductivity. Liaocheng Suntory Stainless Steel provides eight technical standards for stainless steel plates: corrosion resistance, bending processing performance, welding toughness, and excellent stamping processing performance of high-strength stainless steel plates and their manufacturing methods. Specifically, it refers to heating stainless steel plates containing C: 0.02% or less, N: 0.02% or less, Cr: 11% or more, less than 17%, appropriate amounts of Si, Mn, P, S, Al, Ni, and meeting the requirements of 12 ≤ Cr Mo 1.5Si ≤ 17, 1 ≤ Ni 30 (C N) 0.5 (Mn Cu) ≤ 4, Cr 0.5 (Ni Cu) 3.3Mo ≥ 16.0, 0.006 ≤ C N ≤ 0.030 to 850-1250 , and then performing heat treatment with a cooling rate of 1 /s or more. This can become a high-strength stainless steel plate with a volume fraction of martensite above 12%, high strength above 730MPa, corrosion resistance and bending processing performance, and excellent toughness in the welding heat affected zone. Reusing materials containing Mo, B, etc. can significantly improve the stamping performance of the welding area.
Not easily oxidized
The flame of oxygen and gas cannot cut stainless steel plates because stainless steel is not easily oxidized.
5CM thick stainless steel plate needs to be processed using special cutting tools, such as:
(1) Laser Cutting Machine with Larger wattage
(2) Hydraulic sawing machine
(3) Grinding disc
(4) Human hand saw
(5) Wire Cutting Machine.
(6) High pressure water jet cutting
(7) Plasma arc cutting
3. Thickness standard
Comparison of commonly used national stainless steel thickness tolerance standards
Allowable deviation of steel strip thickness
(1) Chinese National Standard (GB) Unit: mm
Thickness |
Allowable thickness deviation |
||
High precision (A) |
Common precision (B) |
||
>600~1000 |
>1000~1250 |
>600~1250 |
|
0.05~0.10 |
---- |
---- |
---- |
>0.10~0.15 |
---- |
---- |
---- |
>0.15~0.25 |
---- |
---- |
---- |
>0.25~0.45 |
±0.040 |
±0.040 |
±0.040 |
>0.45~0.65 |
±0.040 |
±0.040 |
±0.050 |
>0.65~0.90 |
±0.050 |
±0.050 |
±0.060 |
>0.90~1.20 |
±0.050 |
±0.060 |
±0.080 |
>1.20~1.50 |
±0.060 |
±0.070 |
±0.110 |
>1.50~1.80 |
±0.070 |
±0.080 |
±0.120 |
>1.80~2.00 |
±0.090 |
±0.100 |
±0.130 |
>2.00~2.30 |
±0.100 |
±0.110 |
±0.140 |
>2.30~2.50 |
±0.100 |
±0.110 |
±0.140 |
>2.50~3.10 |
±0.110 |
±0.120 |
±0.160 |
>3.10~<4.00 |
±0.120 |
±0.130 |
±0.180 |
(2) Japanese Industrial Standards
Thickness |
Width |
|
<1250 |
≥1250~<1600 |
|
≥0.30~<0.60 |
±0.05 |
±0.06 |
≥0.60~<0.80 |
±0.07 |
±0.09 |
≥0.80~<1.00 |
±0.09 |
±0.10 |
≥1.00~<1.25 |
±0.10 |
±0.12 |
≥1.25~<1.60 |
±0.12 |
±0.15 |
≥1.60~<2.00 |
±0.15 |
±0.17 |
≥2.00~<2.50 |
±0.17 |
±0.20 |
≥2.50~<3.15 |
±0.22 |
±0.25 |
≥3.15~<4.00 |
±0.25 |
±0.30 |
≥4.00~<5.00 |
±0.35 |
±0.40 |
≥5.00~<6.00 |
±0.40 |
±0.45 |
≥6.00~<7.00 |
±0.50 |
±0.50 |
4. Classified by purpose
(1) Bridge steel plate (2) Boiler steel plate (3) Shipbuilding steel plate (4) Armor steel plate (5) Automotive steel plate (6) Roof steel plate (7) Structural steel plate (8) Electrical steel plate (silicon steel sheet) (9) Spring steel plate (10) Solar special plate (Hai Rui Special Steel) (11) Other common Japanese grades in ordinary and mechanical structural steel plates.
5. Classified by thickness
(1) Thin plate (0.2mm-4mm)
(2) Medium plate (4mm-20mm)
(3) Thick plate (20mm-60mm)
(4) Extra thick plate (60-115mm)
Conclusion
When choosing stainless steel plates, consideration should be given to the operating conditions, such as manual or automatic operation, the performance and type of the hot press machine, and the quality requirements for the pressed material, such as hardness and gloss. We also need to consider economic accounting. Each time a new steel plate is polished, it is required to be able to produce a slow quality decorative panel several times. In addition, when selecting the most reasonable thickness of steel plates, their service life, quality, stiffness, and strength requirements under compression should be considered; Thermal conductivity performance; The distribution of pressure and the size specifications of the pressure plate. If the thickness of the steel plate is not sufficient, it is prone to bending, which will inevitably affect the production of decorative panels. If the thickness is too large and the steel plate is too heavy, it not only increases the cost of the steel plate, but also brings unnecessary difficulties to the operation. At the same time, the allowance that should be left during the processing or use of stainless steel plates should also be considered. There is no absolute consistency in the thickness of copper plates, but efforts are made to ensure that the thickness of the same steel plate is as consistent as possible. Generally, for medium-sized saw plates, the thickness tolerance is 0.05-0.15 millimeters. If the requirements are too strict, the grinding cost will also increase accordingly. Generally, steel plates with high tensile strength and hardness have greater resistance to mechanical damage and longer durability, but the cost of grinding and processing is also relatively high.
