A COMPARATIVE STUDY ON THE SINGLE AND DOUBLE-LAYERED DEPOSITION OF ALUMINUM 6063 OVER EN8 MEDIUM CARBON STEEL USING FRICTION SURFACING

This work estimates the optimum process parameters for the double-layer deposition of aluminum 6063 over EN8 medium carbon steel using friction surfacing. The control process parameters like axial force and feed rate of the consumable rod on two different deposition surface conditions, i.e. a good interface and a course interface during the process were investigated. The second layer deposition was performed over the roughness developed after the first layer deposition and contributed largely to the mechanical anchoring mechanism at the second coating interface. Assessment of the mechanical strength at the first coating interface (substrate/coating 1) and second coating interface (coating 1/coating 2) through bending and microhardness tests at both the interfaces was performed. The bending test results disclosed the existence of small delamination with no cracking at the second interface with a feed rate of 150 mm/min at axial force of 5 kN. An increase of 16.2% in the hardness value of consumable aluminum was seen at the first coating interface region. In contrast, the mean hardness at the second coating interface region was nearly the same as that of the consumable rod. Extensive studies of the surface coating and the microstructural features at both interfaces were performed through FESEM and EDAX analyses.