The term steel comes from the Latin "aciarius", and this from the word "acies", which is what the edge of a knife is called in this language. "Aciarius" would therefore be the appropriate metal, due to its hardness and resistance, to be used in the cutting part of weapons and tools.
The exact date on which the technique to obtain iron from the fusion of minerals was discovered is unknown. However, the first archaeological remains of iron utensils date back to 3000 BC. C. and were discovered in Egypt, although there are vestiges of previous ornaments. Quintus Horacio Flaco points out that steel weapons such as the falcata were used in the Iberian Peninsula as early as the century BC. C., while noric steel (in Latin: chalybs noricus) was used by Roman troops.[5] During the Han dynasty of China, steel was produced by melting wrought iron with cast iron, around the century BC. C.[6][7] They also adopted production methods for creating wootz steel, a process that emerged in India and Sri Lanka from approximately 300 BC. C. and exported to China around the 1st century. This early method used a wind furnace, blown by the monsoons.[8][9] Also known as Damascus steel, it was an iron alloy with a large number of different materials, including traces of other elements in concentrations less than 1000 parts per million or 0.1% of the rock composition. Studies carried out by Peter Paufler suggested that its structure included carbon nanotubes, which could explain some of the qualities of this steel - such as its durability and ability to maintain an edge - although due to the technology of the time it is possible that they were obtained by chance and not by a premeditated design.[10].
Between the centuries and crucible steel was produced in Merv, in which steel was obtained by heating and cooling iron and carbon using different techniques. During the Song dynasty of the century in China, steel production was carried out using two techniques: the first produced low-quality steel because it was not homogeneous - the "Berganesque" method - and the second, a precursor to the Bessemer method, removed the carbon with repeated forgings and subjected the piece to abrupt cooling.[11].
Iron for industrial use was discovered around 1500 BC. C., in Metsamor and Mount Ararat, in Armenia.[12] Iron technology was kept secret for a long time, spreading widely around the year 1200 BC. c.
There are no records that hardenability was known until the Middle Ages. The ancient methods for making steel consisted of obtaining soft iron in the furnace, with charcoal and air draft, with a subsequent expulsion of the slags "Slag (metallurgy)") by hammering and carburizing the soft iron to cement it. Then cementation was perfected by melting the cemented steel in clay crucibles and in Sheffield (England) crucible steels were obtained from 1740 onwards.[13] The technique was developed by Benjamin Huntsman.
In 1856, Henry Bessemer developed a method to produce steel in large quantities, but since only iron containing phosphorus and sulfur in small proportions could be used, it was abandoned. The following year, Carl Wilhelm Siemens created another, the Martin-Siemens procedure, in which steel was produced from the decarburization of soft iron casting and iron oxide as a product of heating with oil, coke gas, or a mixture of the latter with blast furnace gas. This method also fell into disuse.
Although in 1878 Siemens was also the first to employ electricity to heat steel furnaces, the use of electric arc furnaces for commercial production began in 1902 by Paul Héroult, who was one of the inventors of the modern method of smelting aluminum. In this method, an electric arc is passed inside the furnace between scrap steel whose composition is known and large carbon electrodes located on the roof of the furnace.
In 1948, the L-D basic oxygen process was invented. After World War II, experiments began in several countries with pure oxygen instead of air for steel refining processes. Success was achieved in Austria in 1948, when a steel factory located near the city of Linz, Donawitz, developed the basic oxygen or L-D process.
In 1950, the continuous casting process was invented, which is used when it is required to produce rolled steel profiles of constant section and in large quantities. The process consists of placing a mold with the required shape under a crucible, which with a valve can dose molten material into the mold. By gravity, the molten material passes through the mold, which is cooled by a water system; as the molten material passes through the cold mold, it becomes pasty and takes on the shape of the mold. Subsequently, the material is shaped. with a series of rollers that at the same time drag it towards the outside of the system. Once the material has been formed into the necessary shape and with the appropriate length, the material is cut and stored.
Currently, some metals and metalloids are used in the form of ferroalloys, which, together with steel, provide excellent qualities of hardness and resistance.[14].
Currently, the steel manufacturing process is completed by the so-called secondary metallurgy. At this stage, the desired chemical properties, temperature, gas content, level of inclusions and impurities are given to the liquid steel. The most common unit of secondary metallurgy is the ladle furnace. The steel produced here is ready to be subsequently cast, conventionally or in continuous casting.
The intensive use that steel has and has had for the construction of metallic structures has seen great successes and resounding failures that have at least allowed the advancement of materials science. Thus, on November 7, 1940, the world witnessed the collapse of the Tacoma Narrows Bridge as it entered into resonance "Resonance (mechanical)") with the wind. Already during the first years of the Industrial Revolution, premature failures of railway axles occurred, leading William Rankine to postulate material fatigue, and during the Second World War there were some unforeseen sinkings of the American Liberty freighters when the steel became brittle due to the mere drop in temperature,[15] a problem initially attributed to welding.