Properties of corrosive coated coatings multi-groove hardfacing on stainless steel

Using the pad welding technique it is possible to regenerate machine parts or improve surface properties such as abrasion, corrosion and aging resistance. To ensure optimum processing conditions and economic efforts should be made, while providing a high deposition efficiency for the small amount of metal in the pad weld substrate. The pad welding process for the test subject should be carried out by preheating to evaporate the moisture and reduce the porosity of the weld. This treatment is required depending on the carbon equivalent. The article presents the results of corrosion tests of multi-groove pads made with the MIG method on a steel substrate. The samples were made of C45E steel. The additional material was a wire made of stainless steel with the factory name CASTOMAG 4554S. The results of previously performed tests allowed determining the optimal process parameters at which we obtain the smallest share of the base material in the padding. Steel samples were prepared and preheated to 300ºC. The hardfacing process was carried out with constant parameters, i.e. current intensity, arc voltage, surfacing speed). Two protective gases were used to apply the additional material: CO2 and argon. The samples were subjected to corrosion tests in two environments (3.5% sodium chloride solution and 0.001 sulfuric acid solution). The assessment of corrosive properties was made on the basis of constant current measurements (potentiodynamic method). The influence of shielding gas on corrosion properties was demonstrated based on the tests.