Number of folded steel
① Use the international chemical element symbol and the national symbol to indicate the chemical composition, and use the Arabic alphabet to indicate the component content:
For example: China, Russia 12CrNi3A
② Use fixed digit numbers to represent steel series or numbers; Such as: United States, Japan, 300 systems, 400 systems, 200 systems;
③ Use the Latin alphabet and order to form the serial number, only to indicate the purpose.
country number
① Use element symbols
② Use, Chinese Pinyin, open-hearth steel :P, boiling steel :F, semi-killed steel :B, killed steel :Z, special killed steel :TZ, Class A steel :A, T8: special 8,
GCr15: Ball bearing
◆ Binding steel, spring steel, such as :20CrMnTi 60SiMn, (with a few parts of the C content)
◆ Stainless steel, alloy tool steel (with a few thousandths of C content), such as :1Cr18Ni9 thousandth (i.e
1%C), stainless C≤0.08% such as 0Cr18Ni9, ultra-low carbon C≤0.03% such as 00Cr17Ni13Mo
Folding mark method
The American Iron and Steel Institute uses three digits to indicate the standard grade of malleable stainless steel. Among them:
① Austenitic stainless steel with 200 and 300 series of digital marks,
② Ferrite and martensitic stainless steel are represented by 400 series numbers. For example, some of the more common austenitic stainless steels
Marked 201, 304, 316, and 310,
③ Ferritic stainless steel is marked with 430 and 446, and martensitic stainless steel is marked with 410, 420 and 440C
Remember, biphase (austenite-ferrite),
Stainless steel, precipitation-hardened stainless steel and high alloys with an iron content of less than 50% are usually patented or trademarked
Rank #.
Folding classification
4-1 Classification Classification:
① National standard GB ② Industry standard YB ③ Local standard ④ Enterprise standard Q/CB
4-2 Categories:
① Product standards ② packaging standards ③ method standards ④ basic standards
4-3 Standard level (three levels):
Y level: International advanced level I level: international general level H level: domestic advanced level
4-4 National standard
GB1220-84 Stainless bar (Grade I) GB4241-84 stainless welding disk (Grade H)
GB4356-84 Stainless welding disk (Class I) GB1270-80 stainless pipe (Class I)
GB12771-91 Stainless welded pipe (Y level) GB3280-84 stainless cold plate (I level)
GB4237-84 Stainless hot plate (Class I) GB4239-91 Stainless Cold Belt (Class I)
market
From the performance of the steel market in May, the social inventory of 304 stainless steel plate has declined, but the overall trend is still weak. The industry expects that the approval of new projects and the recovery of policies are expected to boost market confidence, and the steel market may shake up in June.
Data show that the national 304 stainless steel plate social inventory is 15.949 million tons, a decrease of 1.523 million tons from the end of April, down 8.7% from the previous month. The pace of destocking increased 1.3 percentage points from the previous month. Among them, the building 304 stainless steel plate inventory was 8.531 million tons, a decrease of 1.187 million tons from the previous month; The inventory of sheet metal was 7.418 million tons, a decrease of 336,000 tons from the previous month. In addition, the inventory level index of steel circulation enterprises in May was 26.4%, down 7.1 percentage points from the previous month, reflecting the continuous decline in enterprise inventory pressure.
"Although the steel market is still weak, demand still exists, resulting in a continuous decline in the social inventory of 304 stainless steel plates." Some industry analysts believe that the decline in inventories also has a lot to do with the change in the operating mode of steel traders. Now many steel traders do not stock, using low inventory or even zero inventory to reduce the financial pressure caused by inventory, there is demand from the steel mill directly to the demand side." "He said.
The industry believes that in June will gradually enter the hot and rainy season, and the demand for 304 stainless steel plate will gradually enter the off-season. The support of the cost to the steel market has slightly weakened, and the pressure of the contradiction between supply and demand is still difficult to reduce. However, the market has fallen to a low level, and the policy recovery also helps to boost market confidence, and it is expected that the domestic steel market will show a volatile upward trend in June.
use
304 is widely used in household products (1, 2 types of tableware), cabinets, indoor pipelines, water heaters, boilers, bathtubs, auto parts, medical equipment, building materials, chemicals, food industry, agriculture, ship parts.
Future outlook
Since stainless steel already possesses many of the desirable properties required for building materials, it can be said to be unique among metals, and its development continues. In order to make stainless steel perform better in traditional applications, existing types are being improved all the time, and new stainless steels are being developed to meet the stringent requirements of advanced construction applications. Due to the continuous improvement of production efficiency and quality, stainless steel has become one of the most cost-effective materials chosen by architects. Stainless steel combines performance, appearance and usage characteristics, so stainless steel will remain one of the best building materials in the world. China Stainless Steel Marketing network integrates stainless steel and stainless steel supply chain information service platform, through the establishment of stainless steel industry information, industry observation, enterprise management, stainless steel design, stainless steel forum, equipment and materials, exhibition information, stainless steel knowledge, talent recruitment and other columns, Through the latest information, database, database, analysis and forecast, exchange platform for member units and users around the world, to provide information and consulting services for China's stainless steel industry; Provide trade information and identify business opportunities for stainless steel and related industries; Spread stainless steel culture and home life art, provide stainless steel consumption knowledge. In stainless steel performance is relatively reliable.
Corrosion resistance
The corrosion resistance of stainless steel plate mainly depends on its alloy composition (chromium, nickel, titanium, silicon, aluminum, manganese, etc.) and the internal organizational structure, which plays the main role of chromium.
Chromium has high chemical stability, can form a passivation film on the surface of the steel, isolate the metal from the outside world, protect the steel plate from oxidation, and increase the corrosion resistance of the steel plate. After the passivation film is destroyed, the corrosion resistance decreases.
Requirements can withstand the corrosion of various acids, such as: oxalic acid, sulfuric acid-ferric sulfate, nitric acid, nitric acid-hydrofluoric acid, sulfuric acid-copper sulfate, phosphoric acid, formic acid, acetic acid, etc.
Widely used in: chemical, food, medicine, papermaking, petroleum, atomic energy, construction, kitchenware, tableware, vehicles, household appliances and so on.
