Surface treatment of steels by solar energy

In the recent years, solar energy has started to be considered as a useful energy resource for industry. Outside of its traditional applications, domestic heating and electricity productions, there are scarce references to topics like Surface Treatment of Metals. When solar energy is adequately concentrated, a sufficient energy density is reached to affect a metal thermically, from a mere surface heating to a total fusion depending on the power and duration of the treatment. The present paper sets out the initial results of work on treatment of carbon steel carried out at the Almeria Solar Platform. The results indicate that the maximum temperature (close to 1200 ° C) is reached only a few seconds or minutes after the beginning of the test as a function of thickness and flux density. This suppose an enormous advantage over conventional thermal treatment in terms of time. Another aspect of interest is that the energy is free of charge but, on the other hand, we cannot control it as we like because we depend on weather characteristics. Maximum hardness was found on the metal surface (950 HV) with a treatment depth of between 1.5 and 2 mm. The conclusions reached are therefore that solar energy treatment is ideal for production of structural modifications and even the formation of surface alloys. © 1991.