LEAD-FREE WELD HAVING A LOW MELTING POINT AND ADDITIONS OF RARE EARTH FOR THE ELECTRONIC INDUSTRY,

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The present invention is intended to provide a lead-free welding alloy to the electronic industry for replacing the traditional Lead (Pb) 37%-Tin (Sn) 63% alloy, due to the lead toxicity for living beings and pollution produced by said element in soils and the phreatic surface. The present invention uses non-toxic elements or pollutants such as : Bismuth (Bi) in a ratio of 57.9%, a rare earth element either Pr or Nd in a ratio of from about 0.1% to about 0.001% and Tin (Sn) in a ratio completing a 100%. Said ratios are fixed, the alloys thereof having a melting point of 147.7°C for the Sn-Bi-Pr alloy, and a melting point of 147.6°C for the Sn-Bi-Nd alloy. Moreover, the contact angles are 19° when the selected rare earth element is Pr and 21° when the selected rare earth element is Nd.