History of Metalwork & Fabrication
The history of architectural metalwork goes back to the roots of civilization, perhaps to when an ancient builder went to the local bronze smith for door hinges, and the smith saw an opportunity to add beauty as well as functionality. The craft developed over the centuries, from simple Mediaeval grills into Renaissance florals, and Baroque and Rococo scrolls and gilt. The last century has seen the organic forms of Nouveau, and the elegant lines of Deco.
Since the Renaissance, architectural metalwork and fabrication has gone from strength to strength. Its incredible versatility has seen it used, throughout history, for an increasing variety of constructions.
To describe the range of architectural applications for iron as extensive would be a major understatement – it is used, among other things, for fences, gates, locks, gutters, louvres, plaques, metal doors, ornamental metalwork, patinas and coatings, radiators, lights, hinges, grilles, stairs and weathervanes. The beauty and strength of metal in architecture has been recognised since medieval times. However, it was not used in major artistic endeavours until the Renaissance – a magnificent example is the ironwork of the Palazzo Strozzi in Florence, which was forged in 1490 by Nicolo Grosso in accordance with the designs of architects Simone del Pollaiolo and Benedetto Majano.
By the time of the baroque age in the seventeenth century, the emphasis was on using wrought iron to create increasingly elaborate ornamentation. Wrought iron suited the material and aesthetic needs of the time – it was readily available (only requiring a carbon content of 0.4 per cent), easy to work with and sufficiently malleable for the creation of elegant, graceful decorations.
By the end of the seventeenth century, it had become commonplace for iron to be fashioned into delicate shapes such as leaves and flowers, and by the eighteenth century, these designs had become even more elaborate, with leaves cut from sheets of iron (rather than forged from bars) and then covered with gold.
It was in the nineteenth century that cast iron began to play a major role in architecture, as architects increasingly used iron rather than masonry for structural purposes. With the introduction of wrought iron, metal beams became an efficient, prefabricated method of skeletal construction. Meanwhile, with romanticism and art nouveau flourishing in the UK, there was also a revival in the use of elegant wrought ironwork in architecture, further expanding iron’s many applications.
”Stock metal products” are the bottom rung of the UK metals industry – the angles, beams, channels, sheets, plates, tubing, coil, round, square, hex, and flat bars are regularly used in architectural and ornamental metalwork.
Because of the nature of these metals each of them is produced only in a specific set of shapes, forms and sizes specific to that metal – Hot rolled angles, I beams, and channels are not available in cold finished steel, and stainless steel is not available in any extruded forms, whereas for each extruded aluminum shape made there is a markedly different structural version as well.
Popular opinion has it that stainless steel was discovered in 1913 by Harry Brearley a metallurgist form Sheffield. While experimenting with different types of steel for making weapons, he noticed that a 13% Chromium steel had not corroded after several months.
Generally, Stainless steel is an alloy consisting of Iron with a minimum of 10.5% Chromium added.
The basic resistance of stainless steel occurs because of its ability to form a protective coating on the metal surface. This coating is a “passive” film which resists further “oxidation” or rusting. The formation of this film is instantaneous in an oxidizing atmosphere such as air, water, or other fluids that contain oxygen. Once the layer has formed, we say that the metal has become “passivated” and the oxidation or “rusting” rate will slow down to less than 0.002″ per year (0,05 mm. per year).
Unlike aluminum or silver this passive film is invisible in stainless steel. It’s created when oxygen combines with the chrome in the stainless to form chrome oxide which is more commonly called “ceramic”. This protective oxide or ceramic coating is common to most corrosion resistant materials.
Stainless steel is corrosion resistant, not corrosion free, depending on the environment and type of exposure. Other elements such as Manganese, Carbon, Silicon, Nickel and Molybdenum are sometimes added to the mix in varying amounts, providing enhanced corrosion resistance or malleability.
Stainless steel has a huge range of uses, including: construction, domestic appliances, chemical industry, oil and gas and utilities to name a few.