It is an application of the blasting process that has been gaining ground in the industrial area at an increasingly fast pace. It involves state-of-the-art technology and requires appropriate controls and equipment, as well as knowledgeable and well-trained operators, requirements rarely required when blasting as an industrial tool. The process is identified by several conforming names and language: “Precontrainte Grenailhage”; “Kugeslstrahlen”; “Polliatura” etc. can be translated by “hammering” in Portuguese. However, “shot peening” is the term internationally accepted and understood for its peculiarities.
It is common in the history of industrial development for important inventions to have been discovered but for many years to have been scarce and irregularly used. Rediscovered by the scientific community, they were quickly elaborated and disseminated, becoming internationally renowned.
A typical case is shot peening. In Ur (2700 BC) gold was hammered to increase its hardness. The famous swords of the legendary crusaders (1100-1400) were also hammered to their cool, obtaining exceptional resistance. In the modern era, many companies have researched their effects using blasting instead of hammers, and have abandoned the positive results obtained, only reusing them thirty years later. Shot peening can be defined as a superficial and cold mechanical treatment of metal peels. It can be achieved by evenly distributed impact with rounded objects such as hammers or, more modern and usual, spherical metal or glass particles accelerated at controlled speeds.
The process is closely related to improving the surface metallurgical characteristics of the goals by solving problems of mechanical or thermal fatigue resistance, corrosion, roughness, porosity, hardness, residual stress, conformation, inspection and others related to the manufacture of mechanical or structural parts.