Lightweight supportive wear protection systems against erosive wear by fine particles

Abstract

Machines and equipment wear lead to annual losses of billions. Usually highly stressed mechanical components are not directly hardfaced for wear protection; rather, they are protected by prefabricated plates, which are coated by welding methods for wear protection. The plates are adapted and mounted to the structures to be protected by welding or mounting screws. This procedure leads to an increase in the weight of the wear-protected components, which is not advantageous, especially at high speeds for ventilators subjected to wear. The direct hardfacing of high-strength structures by traditional gas metal arc welding (GMAW) processes typically leads to high dilution, large energy input, and a large heat-affected zone (HAZ), which makes it meaningless, since the required mechanical properties for high-strength steels will be irreversibly lost [13]. By using a modern controlled short arc (CSA) welding method, it is possible to reduce the energy input considerably in the base material. A new application is the surfacing of high-strength steels with the aim of both providing effective protection against wear and preserving the mechanical properties of hardfaced steel. The aim is to support lightweight objects through this concept, leading to a cost advantage in the overall system [13]. As part of this contribution, the possibility to hardface high-strength steel grades (S960) with the CSA welding process is reported. The mechanical-technological properties of the coated steels are carefully studied, as well as the wear resistance and behavior of the applied coatings. The common application of the technology is for structural components for ventilators [13].