Stainless steel
Popularly says, stainless steel is not easy to rust, actually part of stainless steel, stainless steel,
And corrosion resistant to acid. The stainless steel and corrosion resistance is due to its rich chromium oxidation film on the surface
Passivation membrane formation. This doesn't rust and corrosion resistance is relative. Experiment shows that steel in the atmosphere, water
Such as weak medium and nitric acid oxidation medium, the corrosion resistance of the water with steel increases,
When the chrome content reaches a certain percentage, corrosion resistance mutations, which is easy to rust from rust
And never corrosion resistant to corrosion. Stainless steel classification method. According to room temperature, the classification of organizational structure
Markov size, shape, austenite ferrite and duplex stainless steel, According to the main chemical composition classification, basically can
Chromium and nickel chrome steel is divided into two major system; stainless steel According to the purposes are resistant to nitric acid stainless steel sections and sulphuric acid
Stainless steel, stainless steel etc, seawater according to the corrosion resistant type points can be divided into the pitting corrosion resistance, stress of steel
Stainless steel, stainless steel corrosion resistant intercrystal, According to the feature classification can divide again without magnetic steel, cutting
Stainless steel, stainless steel, high strength, low temperature, etc. Due to the excellent stainless steel corrosion resistant, into
Type, compatibility and in a wide range of temperature, so in the series such as heavy, light
Industry, daily necessities and architectural decoration industry in industries has wide application.
All kinds of stainless steel corrosion resistant performance?
304 stainless steel is one kind of universal, which is widely used in production requirements good corrosion resistance and comprehensive performance (
Formability of equipment and parts). 301 stainless steel in deformation when presents the obvious phenomenon, hardening processing
For high strength of various occasions.
302 stainless steel is essentially content of higher 304 stainless steel rolling through the variant, can make its achieved
High strength.
302B is a kind of high content of silicon steel, it has high resistance to high temperature oxidation. 303 and 303Se
Containing sulphur and selenium is respectively for the cutting stainless steel, main requirements and cutting and watch the games. The high degree of hao
Close. 303Se stainless steel is used to make the parts, stude because in this kind of condition, the stainless steel
Good heat processing.
304L carbon content is low, the variations of 304 stainless steel used to weld occasion. Low carbon content
Make the weld near heat affected zone of carbon precipitation, and carbide minimized the exhalation
In some circumstances, stainless steel in the intercrystal corrosion (welding erosion).
304N is a kind of nitrogen stainless steel, add nitrogen is to improve the strength of steel.
305 and 384 stainless steel contains high ni, its processing sclerosis rate is low, suitable for cold formability of high demand
Various occasions.
308 stainless steel electrode used in making.
309, 310, 314 and 330 stainless steel nickel, chrome content is higher, in order to improve steel under high temperature
Antioxidant properties and creep strength. And 30S5 and 310S but 309 and 310, different variations of stainless steel
Only low carbon content, in order to make the carbide weld near by precipitation minimized. A 3.3 stainless steel
Special high carburizing ability and thermal shock resistance.
316 stainless steel and aluminium, 317 type in Marine and chemical industry environment of corrosion resistant ability greatly
Better 304 stainless steel. Which type 316 stainless steel, carbon steel by varieties including low and high nitrogen 316L
Strength and sulphur content 316N stainless steel and high cutting stainless steel 316F.
321, 347 and 348 respectively by titanium is tantalum and niobium, niobium and stabilization of stainless steel, suitable for high temperature
The welding components. 348 is one kind is suitable for the nuclear power industry, stainless steel and the amount of the drill tantalite is certain
The limit.
The physical properties of the stainless steel
Stainless steel and carbon steel, the physical properties of the data of carbon ferrite and slightly higher density, size of stainless steel martensite slightly below the austenitic stainless steel body, According to the steel and iron the resistivity grain size, shape and size martensite austenitic stainless steel sort; Expansion coefficient of similar size and sorting austenitic stainless steel body top and minimum, Steel, iron grain size and shape are magnetic, martensite stainless steel without magnetic austenitic shape, but the cold hardening formation into austenitic phase, when will produce a magnetic treatment methods used to eliminate the martensite organization and restore its magnetic.
Austenitic stainless steel body, compared with has the following features:
(1) high rate of Yin, electrical carbon 5 times.
(2) than the coefficient of linear expansion of carbon, 40 percent, and increased with the temperature coefficient of linear expansion, the value will be improved.
(3) low thermal conductivity, about one-third of the carbon steel.
The mechanical properties of stainless steel
Regardless of stainless steel plate heat austenitic steel or the comprehensive performance of steel body, have enough strength is best, and have excellent hardness and high plasticity, this also is not widely used them. Austenitic stainless steel body with most other metal material similar, tensile strength, yield strength and hardness, with lower temperature and improve, Plastic, but decreases as the temperature. The tensile strength in temperature 15 ~ 80 & # 176, C range growth is relatively uniform. More important is: with the decreasing of freezing storage temperature, its impact toughness reduce slow, brittle transition temperature does not exist. So the stainless steel at low temperature can maintain enough plasticity and toughness.
The heat-resistant stainless steel
Under the high temperature resistant performance refers to, oxidation corrosion resistance, or the performance of gas medium in which high thermal stability, when double sufficient intensity is hot.
