Experimental study on surface erosion of Grade-A marine steel with different curvatures by ultra-high pressure water jet

Abstract

To investigate the erosion mechanism and model of ultra-high pressure (200 MPa) water jet on grade–A marine steel with different curvatures. The ultra-high pressure water jet was induced by plunger pump. The dynamic strain was collected by dynamic strain gauge during impact to explore the mechanical effect. The microstructure was analyzed using three-dimensional topography and a scanning electron microscope. The results show that the average microstrains of samples with the curvature of 1/4 m−1, 3/4 m−1, and 5/4 m−1 impacted by ultra-high pressure water jet are 707, 952 and 1053, respectively, and the strain amplitudes are 300∼700, 300–600 and 300–560 respectively. The force exerted on the surface of the curved samples manifested as cyclic, pulsating, and alternating stress. With the curvature increase, the roughness decreases by 19.22%, 48.64%, and 21.31%, respectively. Meanwhile, surface damage, material removal, pits, holes, and cracks decrease. Finally, the erosion mechanism is clarified, and the erosion model of the ultra-high pressure water jet on grade–A marine steel with different curvatures is established.}

Keywords

• Ultra-high pressure water jet
• Grade-A marine steel
• Dynamic strain
• Surface morphology