III - Alloying
Our series of articles on the steel production process in part two we have reached the end of the production process. However, in order for the steel to meet the crane manufacturing to the stringent requirements of the process, refinement and alloying are necessary. Today's article is about these processes.
OK, but what is an alloy?
Industry uses a wide range of different steels, and different applications require different steels with different properties.
The most appropriate material for the intended use a mixture of the basic material (steel) and other materials (metallic or non-metallic) we can produce. This process is called alloying.
Materials that affect or modify the properties of the raw material in a way that is beneficial to us and to its use, we call it combining.
Some of these substances are still pig iron production is introduced into the steel, while the other part is steel production is added to the steel, as discussed earlier.
A low affinity noble alloyers (nickel, cobalt, molybdenum, copper) can already be fed into the blast furnace together with the charge materials.
In contrast, the high affinity combiners (chrome, vanadium, tungsten, aluminium, titanium) should only be added to the liquid steel after the deoxidation process.
Coatings and their effect on steel
The following are the most commonly used alloying materials in steel production:
Carbon: increases the tensile strength of steel, but reduces its elongation, formability and tensile properties.
Manganese: also increases the tensile strength and the transition temperature during manufacture, but (to a lesser extent than carbon) reduces elongation.
Silicon: As a strength enhancer, up to 1.5% silicon, the elongation of steel is only slightly reduced. However, an increase in the silicon content of the alloy significantly reduces the electrical conductivity of the steel.
Aluminium: It is not used as a single alloy in larger quantities. However, it is an alloy with chromium and silicon for heat-resistant steels and with nickel and cobalt for permanent magnets.
Nickel: It improves the hardenability of steel and is therefore a very popular alloying agent.
Chrome: Like nickel, it greatly increases the hardenability of steels. It is a very common alloying element in tool steels. With a chromium content above 12% and low carbon content, the steels have good acid resistance.
Molybdenum: A carbide-forming element that increases the hot strength and durability of steel and also improves the ductility of the steel alloy. When combined with tungsten and vanadium, it reduces the brittleness of stainless steels.
Copper: The main alloying agent for steels resistant to atmospheric corrosion.
Titanium: It slightly increases the tensile strength of steel.
Niobium: It is used for alloying high-temperature steels.
Ón: Increases the machinability of steels.
Steel alloys made using different alloys therefore cover the industrial use almost the whole spectrum.
Steel as a raw material but can be further shaped by further heat treatment, cold and hot working. Some of its properties can still be altered. In the next, final part of this series, these processes will be discussed.
