Steel Plate Knowledge Summary

Four criteria for the selection of hot rolled steel plates

Relationship between mechanical properties and formability and serviceability To obtain the desired shape of a Steel plate, it must be permanently deformed and the process adopted can be partial or integral bending, deep drawing, tensioning or a combination of these forming methods.

1. The yield strength of thin steel plates indicates the formability and strength after forming. For the forming of ordinary carbon steel plates, a high yield point value is often associated with excessive springback, easy breakage during forming, fast wear of abrasives and defects due to poor plasticity. However, the yield point of the material is less than 140Mpa, and may not be able to withstand the stresses applied during the forming process, for more complex or complex forming process or stamping processing of the steel plate, usually requires a relatively low yield strength value, and the smaller the yield ratio, the better the forming properties of the steel plate.

2. The cold formability of the thick steel plate is directly related to the yield strength and elongation of the material. The lower the yield strength value, the smaller the stress required to produce permanent deformation; the higher the elongation value, the higher the ductility can be allowed to withstand large deformations without fracture.

3. For building structures, bridges and mechanical structural components of the steel plate, in order to prevent fracture of the components, the requirements of the steel material has the characteristics of the tensile strength, and to prevent deformation of the components, but also require the steel material has a certain yield strength, so the steel for such purposes are required to specify the minimum value of tensile strength, yield strength or range of values.

4. For impact load deformation, such as ships, bridges, oil and gas pipelines with steel plate, in order to prevent its use of brittle fracture, but also require a certain high enough impact toughness – impact work value.

5. Selection methods for steel plate species categories

Hot rolled steel products include strips (coils) and steel sheets sheared from them. The steel strip (coil) can be divided into straight hair rolls and finishing rolls (sub-rolls, flattening sub-rolls and slitting strip rolls).

As a result of straight hair volume without re-rolling, not remove the steel strip head and tail size change part and without straightening and leveling, so straight hair volume with tongue and fish tail, and easy to happen head and tail thickness, width uneven, side wave shape, folded edge, tower shape and open volume appear wrinkles (waist fold) and other defects, so the surface quality of the steel plate, plate shape requirements are relatively high use, should not use hot-rolled straight hair volume, but should be selected after finishing line re-roll, leveling of flat volume.

Analysis of the classification of stainless steel cold rolled sheets

Stainless steel cold rolled steel plate is a stainless steel plate produced by cold rolling process, the thickness is not more than 3mm for thin plate, the thickness is more than 3mm for thick plate. It is used to make corrosion resistant parts, pipelines, containers, medical equipment, marine equipment of petroleum and chemical industry, etc. Its classification and grades are as follows.

1. Austenitic steel
   In addition to the same as the hot-rolled part (29 kinds), there are: 2Cr13Mn9Ni4(2) 1Cr17Ni7(3) 1Cr17Ni8

2.  Austenitic – ferritic steel
   ( In addition to the same as the hot-rolled part (2 types), there are: (1) 1Cr18Ni11Si4AlTi (2) 1Cr21Ni5Ti

3.  Ferritic steel
   In addition to the same as the hot-rolled section (9 types), there are: 00Cr17

4.  Martensitic sections　　
   In addition to the same as the hot-rolled section (8 kinds), there is 1Cr17Ni2 5. Precipitation-hardening steel: the same as the hot-rolled section

Three classifications of steel

1. Ferrous metals are alloys of iron and carbon. Examples include steel, pig iron, ferroalloys and cast iron. Steel and pig iron are both iron-based alloys with carbon as the main added element, collectively known as iron-carbon alloys.
   Rebar pig iron is a product made by putting iron ore into a blast furnace and smelting it, mainly for steel making and manufacturing castings.
   Casting pig iron is put in the smelting furnace, that is, to get cast iron (liquid), the liquid cast iron cast into castings, this cast iron is called cast iron parts.
   Iron alloy is an alloy composed of iron and silicon, manganese, chromium, titanium and other elements, iron alloy is one of the raw materials for steelmaking, in steelmaking to do steel deoxidizer and alloying elements additive with.

2. the steelmaking pig iron into the steelmaking furnace according to a certain process of melting, that is, to get steel. Steel products are ingots, continuous casting billets and direct casting into a variety of steel castings, etc.. Usually referred to as steel, generally refers to rolled into a variety of steel steel. Steel is a ferrous metal but steel is not exactly the same as ferrous metal.

3. non-ferrous metals, also known as non-ferrous metals, refers to metals and alloys other than ferrous metals, such as copper, tin, lead, zinc, aluminium, as well as brass, bronze, aluminium alloys and bearing alloys. Also used in industry are chromium, nickel, manganese, molybdenum, cobalt, vanadium, tungsten, titanium, etc. These metals are mainly used as alloy add-ons to improve the performance of metals, including tungsten, titanium, molybdenum, etc. are mostly used in the production of carbide for cutting tools. These non-ferrous metals are known as industrial metals, in addition to precious metals: platinum, gold, silver, etc. and rare metals, including radioactive uranium, radium, etc.