Effect of Grit Blasting and Subsequent Cold Spraying on Low-Cycle Fatigue Crack Growth of Q355B Steel

AbstractLow-pressure cold spraying was used to deposit A5052 and Al coatings on structural Q355B steel to improve its fatigue performance. Through the experiments and finite-element simulation, the fatigue crack growth behavior of Q355B steel substrate after polishing, grit blasting, and cold spraying with A5052 and Al powders were compared and analyzed. The bonding strengths of coatings to the substrate surfaces were measured through tensile testing. Three-point bending testing, with fracture morphology analysis and extended finite-element simulation, was conducted to analyze the effects of cold spraying coatings on the crack growth of Q355B steel. Results showed that the effects of grit blasting and cold spraying with A5052 and Al powders, and their combined effect, were conducive to the enhanced fatigue performance of Q355B steel.