Study On Preparation And Performance Of Aluminum-based Composite Anti-skid Coating

The article takes the anti-skid coating of the deck of large ships in the marine environment as the research background,according to the anti-skid,wear-resistant and corrosion-resistant properties of the anti-skid coating,fully utilizes the corrosion resistance of the aluminum-based coating,prepared the element Ti,Ni and potassium hexatitanate whisker reinforced aluminum-based composite non-slip coating by supersonic arc spray.By adjusting the composition ratio of elements and potassium hexatitanate whiskers,the coatings of each group were characterized,and the microstructure and phase composition,microhardness and bonding strength of each group of coatings were analyzed.The research focused on the tribological behaviors of the coating,such as the anti-skid performance and wear resistance,simulated the influence of the coating due to the temperature difference between day and night in the marine climate,and tested the thermal shock resistance and corrosion resistance of the coating.Pure Al coating,three gradient Al-Ti coating,Al-Ni coating and Al-whisker coating with elemental and whisker content of 10%,20%and 30%were prepared by powder core wire.Through scanning electron microscope?SEM?observation,it was found that the surface of each coating was flattened and spread around,the cross-sectional shape of pure Al coating showed a whole block structure,and the cross-sectional shape of Al-Ti coating was a layered structure.The higher the Ti content,the more obvious the layered structure.The composition of the Al-Ni coating cross-section layer is complex and interlaced,and the gradient changes with the Ni content.The higher the Ni content,the brighter the color.Potassium hexatitanate crystals in the Al-30%whisker coating cross-section can be observed,with obvious agglomeration in the coating.Through X-ray diffraction analysis?XRD?,tensile test,microhardness and other detection analysis,the relationship between the coating phase composition and mechanical properties was studied.The test results found that the phase of the pure Al coating is mainly Al,the main phase of the Al-Ti coating is Al and Al₃Ti,etc,the main phase of the Al-Ni coating is Al,Al_1.1Ni_0.9.9 and Al_0.42Ni_0.53,the hard phases such as intermetallic compounds added by Ti and Ni elements greatly increase the microhardness of the coating,and the bonding strength also increases slightly.The bonding strength of Al-Ti coating can be increased to more than 40Mpa.The addition of potassium hexatitanate whiskers has little effect on the microhardness of the coating,and the bonding strength decreases slightly as the content of potassium hexatitanate whiskers increases.The porosity of each coating is below 3%,the porosity of the pure Al coating is the lowest,and the addition of elements Ti,Ni and potassium hexatitanate whiskers increases the porosity of the coating.Through the friction and wear test,combined with the observation of the morphology of the coating before and after wear,the change rule of the friction factor of the coating and the wear resistance of the coating in different states were studied,the failure mechanism of the coating wear was analyzed.The results show that,under dry friction,the addition of Ti and Ni element can be improved and the friction coefficient of the coating increases with increasing content.The Al-Ti coating is slightly higher than the Al-Ni coating,and the Al-30%Ti coating The friction factor can be up to 0.86,which meets the index requirements.The dry friction coefficient of Al-whisker coating and pure Al coating is similar.In the wet friction state,the friction factor of the coating is slightly lower than in the dry friction state.The wear quality of Al-Ti and Al-Ni coatings is lower than that of pure Al coatings,and the addition of elements improves the wear resistance of the coatings.The wear quality of Al-whisker coating is not much different from that of pure Al,but it increases with the increase of potassium hexatitanate whisker content.The wear mechanism of the composite coating is mainly abrasive wear and adhesive wear.Al-30%Ti coating interacts with corrosion and wear under corrosive media.Fatigue cracks appear on the coating surface,and the effects of surface fatigue wear and corrosion wear increase.The coating showed no obvious cracks and damages under the thermal shock cycle test at 600?,and it has good thermal shock resistance.The thermal shock resistance of pure aluminum coating is good,the number of thermal shocks reaches331,the lowest thermal shock among Al-Ti coatings is Al-30%Ti coating,the thermal shock frequency is 232,The thermal shock frequency of the Al-30%Ni coating is 240,and the thermal shock frequency is 252 when the amount of potassium hexatitanate whisker is 30%.The addition of elements and potassium hexatitanate whiskers degrades the thermal shock resistance of the coating.The potentiodynamic polarization curve shows that the corrosion current of the pure aluminum coating is the smallest and the corrosion resistance is the best.The changes of the corrosion current in each group of the Al-Ti coating,Al-Ni coating and Al-whisker coating are small,Al-The whisker coating has a significant decrease in corrosion resistance compared to the other groups.After the element and potassium hexatitanate whiskers are added,the corrosion current of the coating increases and the corrosion resistance decreases.After the neutral salt spray test for 2000h,there was no obvious red rust.The coatings were all swollen and cracked,indicating that the aluminum-based coating has good corrosion resistance,and the aluminum-based coating can resist the corrosion of the marine corrosive environment and meet the MIL-PRF-24667 standard index requirements.