Technological and metallurgical characteristics of MIG soldering on the example of joining aluminum bronze and structural steel

Abstract

MIG soldering, classified as process 973 according to SRPS EN ISO 4063:2023 [1], is a joining process that uses an electric arc between a consumable electrode and the base material. In this process, the base material remains unmelted, while the joint is formed by melting a filler material with a lower melting temperature. Since industrial application may require the joining of materials that are difficult or unsuitable to join by conventional fusion welding, this paper provides a systematic overview of the MIG brazing process from the perspective of normative classification, theoretical foundations, metallurgical bonding mechanisms and key process parameters. The analysis is presented through the example of joining AMPCO®18 aluminium bronze and structural steel SRPS EN 10025-2 - S355J2+N, with particular emphasis on the difference compared to conventional MIG welding, as well as on the industrial application of process 973 in accordance with the current ISO and EN standards. The obtained results show that an adequate soldering technology was selected, enabling the successful application of this joining method in practice.