When selecting a material for the manufacture of metal products must take into account several characteristics, including its modulus and hardness.This structural insensitive index depends only on the nature of the material of which the power elements - stringers, frames, flat plates, etc.
highest modulus of rigidity is steel, which, in turn, by its chemical composition is of two kinds.Firstly, this alloy steel in which alloying elements are added specifically to provide any of the required properties.
The main elements that influence the properties of steel - is carbon, silicon and manganese.By increasing its carbon content makes the steel stronger and harder, while reducing its ductility.Silicon is administered as a deoxidizer, but when its content is more than one percent much deteriorates the weldability of steel: the weld is brittle.And an element manganese increases cold brittleness and toughness of the steel, also being a good deoxidizer.
Typically, in addition to iron and carbon, is added to any single component, so alloy steel is classified as three-component, four-component, and so on. G. Sometimes it differs for the title of the alloying element, such as chromium, chromium-nickel, etc. hromonikelmolibdenovaya
alloy steel contains more than one percent of chromium or nickel.If it contains more than 0.5% of vanadium, titanium, molybdenum, niobium, nitrogen, copper, et al., It is considered by these alloy elements.
Depending on the number of added components, stainless steel is divided into the following subclasses:
- high-alloy steel, in which the total content of alloying elements is not less than ten percent;
- srednelegirovannoj - no more than eight per cent;
- alloy steel, which adds only one element with a content over the upper limit of not more than two percent.
Usually alloying elements greatly increase the cost of steel, especially since some added elements in themselves are deficient expensive metals.Accordingly, their addition in the steel must be carefully grounded.
Alloy Steel is marked as follows: the first two numbers indicate the carbon content (hundredths of a percent), the letters arbitrarily designate added alloying element figure after them - the content of this element as a percentage.The letter "A", which stands at the end of the marking means that the high quality steel with a low content of phosphorus and sulfur.
Another variation of the chemical composition of steel - carbon.It is because of the simplicity and cheapness of production increasingly used in many industries.
One of the purposes of steel is its use in the manufacture of measuring and cutting tools, machine parts, dies of cold and hot deformation.
Tool steel case and stainless and carbon, and depending on the rules governed by the guest, for each specific steel products need to use steel having a specific chemical composition.
For example, surgical tools, drills, chisels, hammers, screwdrivers, saws, milling cutters, etc. Used a certain category of steel - high-alloy, high-speed.It has high hardness, heat resistance and durability.These unique properties are obtained by adding special doping with tungsten carbide and complex heat treatment.
to hammer, cold and hot dies, molds and others. Steel is used brands such as H6VF, 9X, 5HNM etc.
