Study On Fabrication And Tribological Properties Of Bionic Self-Lubricating Micro-Texture

How to improve the friction and wear performance of the friction pair under dry friction and boundary conditions has been a problem in the field of friction.Aiming at the lubrication problem under the boundary friction and dry friction,this paper draws on bionic tribology,and uses the snake skin and the cricket footpad as the bionic object,to propose two kinds of bionic micro-textures with self-lubricating function.The manufacturing process was studied,while the corresponding self-lubricating mechanism was analyzed after the investigation of its tribological properties.The main work of this paper is as follows:?1?Biomimetic micro-texture and its self-lubricating designThe wear-resistant texture of snake epidermis and cricket foot pad was selected as biomimetic object,and the planar model of bionic hexagonal array was obtained by planarization modeling.Using H62 brass and 20CrMo alloy steel as texture carriers,two kinds of self-lubricating bionic textures,nickel-plated hexagon and sintering-fixed hexagon,were designed by combining nickel and solid lubrication powder respectively.?2?Fabrication of bionic self-lubricating micro-textureThe nickel plating process was innovated into the lithography process to produce a nickel-plated bionic regular hexagonal texture,and a series of nickel-plated bionic hexagonal textures with uniform nickel-plating texture and no leakage-free plating phenomenon were fabricated on H62 brass.The hexagonal array texture was fabricated on the 20crmo substrate by adjusting the laser parameters,and the composite solid lubrication powder was filled into the texture.Then through vacuum sintering,the sintering-fixed bionic hexagonal texture was successfully obtained.?3?Tribological properties of nickel-plated bionic micro-texture and its self-lubricating mechanismThe friction and wear characteristics of nickel-plated bionic texture under boundary lubrication conditions are studied by the friction method of line contact.Compared with the smooth sample,the nickel-coated bionic texture sample has a maximum friction coefficient of43.6%and a maximum wear rate of 42.86%.Nickel-plated bionic texture significantly reduces oxidation,furrow and adhesive wear on the worn surface.In the sliding friction process,the nickel-plated bionic texture sample forms a surface lubricating film composed of copper-nickel alloys,NiO and Ni₂O₃,improving interfacial lubrication,repairing the micro-defects formed by abrasion,and effectively preventing oxidation of the matrix.?4?Tribological properties of sintering-fixed bionic micro-texture and its self-lubricating mechanismUsing the friction method of surface contact,under the dry friction of different working conditions,the in-depth study and analysis of the biomimetic micro-texture properties of the burnt solids showed that the burnt bionic texture samples can quickly enter the stable friction stage;Under heavy load,the friction and wear properties of self-lubricating samples are greatly improved compared with smooth samples.After the addition of the grease medium,the bionic self-lubricating sample can consistently achieve a lower coefficient of friction.Self-lubrication mechanism studies show that the biomimetic micro-texture can contain the abrasive debris,and at the same time,the solid lubricant is extruded under shear force and frictional heat to form an interface lubrication film.