Al - Melting point 660 C -Aluminium
It is the strongest de-oxidised and combines with nitrogen.Thus reducing the suscepbility to strain againg.In small additions restricts grain growth.As Aluminium together with nitrogen nitrid form a hight hardness.It Is mostry an allowing element in nitriding steel.Aliminium improves the scare resistance and therefore often used as an allowing element in terific heat resisting steel.Because of the increase in the coercivity is used as an alloying element in Iron-Nikel-Cobalt-Aluminium permanent magnet alloys.
B - Melting point 2040 C - Baron
Improves the deep hardening of contructional steels and produces therefore an increase in the core hardness of case hardening steels.With Baron austenitic 18/8 Crome-Nikel steels can achieved higher elastic limits by the proces of precipitation hardening,but the corrosion resistance is lowered.As Baron has a high neutron absorption croos section.It is alloyed with steel for screening from nuclear instalation.C - Carbon
Carbon is the foremost alloy element of steel and it has the farthest reaching influence on it.In addition to carbon every unalloyed steel contains silicon,manganese,phosphorus and sulphur which are introduced unintentionally during the manufacture.The addition of further alloy elements to produce specific,desired effects and the intentional increae of the content rises the mecanical strength and the hardening properties of the steel improve but its elasticity,forging,welding and cutting propenies suffer.The Carbon content has subtantially no influence at all on the resistance to water,acid and hot gases.
Ca - Melting point 850 C - Calcium
Together with Silicon in the form of Ca Silicon put into actiom for de-oxidation.Ca increases this scale resistance of heat conductor material
Ce - Melting point 775 C - Cerium
Its a strong de-oxidant and promotes desulphurising .Improves the hot working of high alloy steel and also the non scaling properties of heat resisting steel.
Co - Melting point 1492 C - Cobalt
Does not form carbide.It hinder the grain growth at higher temperatures and greatly improves the resistance to tempering and the hot tensile strength its therefore,often alloy element of hight speed steel.hot work steels,and heat resisting raw material.Its acts favourably on the grapic formation,and greatly increases residual magnetism coercive force,and thermal conductivity,therefore the alloy basis for hight grade permanent magnet steels and alloys.It subyected to neutron rays it form a strong radio active isotope Cobalt so for which reason it is undersirable in steels for atom reactors.
Cr - Melting point 1920 C - Chromium
Increases the hardeness and strengthh and only minimal reduces the elasticity.It improves the resistance to heat and non scaling properties.With higher Crome content the steels become corrosion resistant and with Carbon forms a high wear resisting Carbide.The welding properties deteriorate in pure Chromium steels with increasing Chromium content.Cromium is a strong Carbide former.The tensile strength of the steel rises by 8-10 kg/mm2 per 1% Chromium.The yield point is likewish increased,however not at the same rate,but the noh impact value is lowered.
Cu - Melting point 1084 C - Copper
H - Melting point -263 C - Hydrogen
Mn - Melting point 1244 C - Manganese
Manganese improves the strength properties of steel,while only slightly imparting its elasticity;furthemore,manganese has a favourable influence on the forging and welding properties.A higher content of manganese in the precent of carbon increases wear resistance very substantially.With up to 3% of Mn the tensile strength of the steels in increases by about 10kg/mm2 for every percent of Mn,content above 3-8% the increase rises more slowly and more than 85 of Mn it drops off again.The yield point behaves in asimiliar manner.Manganese increases substantially the the dept of hardening.
Mo - Melting point 2610 C - Molybdenum
Molybdenum improves the tensile strength and especially the heat resistance and it has also a favourable influence on the welding properties.Steel with a higher Mo content fends to be difficult to forge.Mo is frequently used in conjunction with cromium.The behaviour of Mo resembles that of tungsten.When used in alloy steels in combination with cromium and nickel,Mo may produce high yield point and tensile strength values.Mo has a strong tendency to form carbide and is the alloy element of choice in high speed and hot working steels,in austenitic corrosion resistant steels,case hardening and healtresting steel as weel as in heat resistant steels,also in view of the diminuation to over drawing britlleness.
N - Melting point -210 C - Nitrogen
Nb/Cb - Melting point 1950 C - Niobium/Columbium
Ta - Melting point 2977 C - Tamaium
These alements appear almost always together and are very difficult to separate from one another,so that they are usually always together,mainly as stabilisers.
Ni - Melting point 1453 C - Nickel
Nickel rises the strength of steel less than does silicon or magnese with the elasticity droping only insignificantly.Ni ensures good inrough hardening,espicially so when the steel contains also Cromeium.Crom nickel steel are stainless and resistant to scaling and also heat resistant
.Nickel does not impair the welding properties.Nickel increases the notch impact value of structural steel considerable,especially at low temperatures. In the spere of steel alloying nickel
is especially suitable for use in austenitic steels,steels resistant to corrosion and scaling and in casehardening and heat treating steels to improve their toughness.
O - Melting point -218,7 C - Oxygen
Its harmful to steel but this specific influence depend upon the type and composition of the compounds as well as the shape and distribution.The mechanical properties,especially notch impact value are lowered primarilly in transverse direction,while the tendency to ageing brittleness increase.
P - Melting POINT 44 C - Phosphorus
Pb - Melting point 327 C - Lead
S - Melting point 118 C - Sulphur
Se - Melting point 217 C - Selenium
Si - Melting point 1410 C - Silicon
Like Magnese ,Silicon is present in all steels since the iron ores used in their manufacture contain a varying amount of it,Further Silicon steming from the refractory lining of the furnace is introduced into the melt during the manufacturing of steel.The term Silicon steels however,includes only steels having a Silicon content above 0,40%,Si is not a metal but rather a so-called metalloid like,for example,phosphorus and sulphur Silicon increases the mechanical strength,the resistance to scaling and the density;aspecially of cast steel.The alasticity is only insignificantly affected;while the tensile strength is increased by about 10kp/mm2 for each percent of Si and the yield point is raised to similiar degres.Steel having a higher content of silicon turns coarsely granular.A high silicon content about 14% enables steel to resist chemical attacks but it can no longer be forged.
Ti - Melting point 1812 C - Titanium
Avery hard metal.Strong carbide former.Is an alloying element mainly in stainless steels for stabilising against intergranular corrosion apart from this it has grain refining properties.
V - Melting point 1730 C - Vanadium
A small addition improves the hot hardness and reduces the grain growth.Vanadium acts especially favourably in structural and tool steels,in high speed steel increases the cutting properties.Vanadium is the strong carbide former.Increases the tensile strength and yeald point,especially however the hot hardness properties of the steels.Vanadium is propered in combination with Chromium in structural and heat resisting steels and in combination with Tungsten in hight speed and hot work steels.
W - Melting point 3380 C - Wolfram
Tu - Tungsten
Tungsten improves the strength properties it increases subtantially the hardness and the life of cutting edge and it also responsible for high heat resistance values.Tungsten is therefore used as an alloy element for high speed and heat treating steels.The tensile strength and yeald point values of the steel are increased by about 4kg/mm2 for everi percent of Tu added.Tungsten has a very strong tendency to form carbide and is primarily used in heat resistant steel since it renders them resistant to over drawing and heat.
Zr - Melting point 1861 C - Zirconium
A carbide former.An Extra element for de-oxidation,desulphurisation and eliminating Nitrogen because it leaves minimal de-oxidation products increase the life of heat conducting steel.
EXPLANATION to D I N ABBREVIATIONS
The preceding number indicates the average carbon content x 100,subsequently followed by the added alloy elements in short designation.The figure immediately following,indicates the average content of alloy added as stated on the undermentioned factor in case none other than alloy or high alloy steels.
Factor for Co, Cr, Mn, Ni, Si and W = X 4
Factor for Al,Cu,Mo,Cu,Mo,Ti and V = X 10
Factor for C ,N , P and S = X 100
Provided that Al 0,1%,Cu 0,25%,Mn 0,8%, Si 0,5% and Ti 0,1% are not exedeed,the steel concerned is unalloyed,Low alloy steels contain as a rule not more than 5% or alloy elements,while high alloy steels contain them in a proportion higher than 5%.
With alloy content 5% upwards the multiplication falls away and X is put in front of carbon content.
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