Nanoparticle-reinforced metal matrix composite coatings have significant potential in mechanical part surface strengthening owing their excellent mechanical properties.This paper reports a phenomenon in which the grai...Nanoparticle-reinforced metal matrix composite coatings have significant potential in mechanical part surface strengthening owing their excellent mechanical properties.This paper reports a phenomenon in which the grain orientation gradually evolves to(220)as the deposition current density increases when preparing nanoparticle-reinforced nickel-based composite coatings through jet electrodeposition(JED).During the preparation of the Ni-SiC composite coatings,the deposition current density increased from 180 A/dm2 to 220 A/dm2,and TC(220)gradually increase from 41.4%to 97.7%.With an increase of TC(220),the self-corrosion potential increases from−0.575 to−0.477 V,the corrosion current density decreases from 9.52μA/cm^2 to 2.76μA/cm^2,the diameter of the corrosion pits that after 10 days of immersion in a 3.5 wt%NaCl solution decreases from 278–944 nm to 153–260 nm,and the adhesion of the coating increases from 24.9 N to 61.6 N.Compared a conventional electrodeposition(CED),the Ni-SiC composite coating using JED has the advantages of a smooth surface morphology,high corrosion resistance,and strong adhesion,which are more obvious with an increase in TC(220).展开更多
The nickel-based superalloy Inconel 718 is treated with Coupled Ultrasonic and Electric Pulse Treatment(CUEPT),and the surface grain is refined from the average size of 9550.0 nm to287.9,216.3,150.5,126.3,25.8 nm by d...The nickel-based superalloy Inconel 718 is treated with Coupled Ultrasonic and Electric Pulse Treatment(CUEPT),and the surface grain is refined from the average size of 9550.0 nm to287.9,216.3,150.5,126.3,25.8 nm by different effective treatment currents,respectively.The ultraprecision turning experiments are carried out on the processed workpiece after CUEPT.The experimental results show that the average cutting force increases with the decrease of surface grain size.Moreover,a mathematical model that can describe the relationship between grain size and cutting force is established,and the calculated results match the experimental results well.The calculated results also indicate that the variation of cutting force caused by the same variation of grain size decreases as the degree of grain refinement increases.Finally,the influence mechanism of grain refinement on cutting force is analyzed.The improvement of stability of grain boundaries and the increase of number of grain boundaries cause the increase of cutting force after grain refinement.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51675535)Major Research Project of Shandong Province of China(Grant No.2019GGX104068)+3 种基金Key Pre-Research Foundation of Military Equipment of China(Grant No.6140923030702)National Science and Technology Major Project of China(Grant No.2017ZX05072)Graduate Innovation Protect of China University of Petroleum(East China)(Grant No.YCX2020059)Science and Technology Support Plan for Youth Innovation of Universities in Shandong Province of China(Grant No.2019KJB016).
文摘Nanoparticle-reinforced metal matrix composite coatings have significant potential in mechanical part surface strengthening owing their excellent mechanical properties.This paper reports a phenomenon in which the grain orientation gradually evolves to(220)as the deposition current density increases when preparing nanoparticle-reinforced nickel-based composite coatings through jet electrodeposition(JED).During the preparation of the Ni-SiC composite coatings,the deposition current density increased from 180 A/dm2 to 220 A/dm2,and TC(220)gradually increase from 41.4%to 97.7%.With an increase of TC(220),the self-corrosion potential increases from−0.575 to−0.477 V,the corrosion current density decreases from 9.52μA/cm^2 to 2.76μA/cm^2,the diameter of the corrosion pits that after 10 days of immersion in a 3.5 wt%NaCl solution decreases from 278–944 nm to 153–260 nm,and the adhesion of the coating increases from 24.9 N to 61.6 N.Compared a conventional electrodeposition(CED),the Ni-SiC composite coating using JED has the advantages of a smooth surface morphology,high corrosion resistance,and strong adhesion,which are more obvious with an increase in TC(220).
基金supported by National Natural Science Foundation of China(No.51875579)the Fundamental Research Fund for the Central Universities,China(No.19CX02023A)+2 种基金the Major Research Project of Shandong Province,China(No.2019GGX104068)the Science and Technology Support Plan for Youth Innovation of Universities in Shandong Province,China(No.2019KJB016)Source Innovation Project of Qingdao West Coast New Area,China(No.2020-82)。
文摘The nickel-based superalloy Inconel 718 is treated with Coupled Ultrasonic and Electric Pulse Treatment(CUEPT),and the surface grain is refined from the average size of 9550.0 nm to287.9,216.3,150.5,126.3,25.8 nm by different effective treatment currents,respectively.The ultraprecision turning experiments are carried out on the processed workpiece after CUEPT.The experimental results show that the average cutting force increases with the decrease of surface grain size.Moreover,a mathematical model that can describe the relationship between grain size and cutting force is established,and the calculated results match the experimental results well.The calculated results also indicate that the variation of cutting force caused by the same variation of grain size decreases as the degree of grain refinement increases.Finally,the influence mechanism of grain refinement on cutting force is analyzed.The improvement of stability of grain boundaries and the increase of number of grain boundaries cause the increase of cutting force after grain refinement.
