Antiwear And Artifriction Research Of Millimeter Texture On The Friction Pair Surface

In the mechanical field, surface texture technology nowadays is widely used to reduce friction and wear, it is called the three friction reduction methods with choosing friction materials and the improvement of lubrication. At present, lots of research and application of surface texture are about the bearing. Transmission screw pair plays a crucial role in the transmission of mechanical equipment, and it is widely used in machinery manufacturing industry. Due to the friction coefficient of sliding screw is big, this will lead to accelerate wear of the meshing surfaces at both ends of the screw nut. Not only affects the transmission precision, but also can lead to fatigue failure of thread. Therefore, it’s of vital importance to improve the stability and service life of the sliding screw friction impairment.In this paper, based on the ladder lubrication theory of surface texture, the design theory of texture and the principle of friction and wear, combined with FLUENT numerical simulation,focusing on the helical friction in various texture parameters of the friction and wear properties.First, the drive screw was simplified as a planar contact model, the antifriction lubricating of surface texture was researched under the situation of linear motion. It was found that when the texture surface area ratio Sp increases, the top wall dimensionless average pressure values are basically increases while the texture is uniformly distributed. Under the same texture area occupancy, in the research range of texture parameters, parallel to the direction of movement of the length should be as long as possible (X=5d), so that the pressure can be made to maximize the average value of the top wall dimensionless, which can achieve the best effect of lubrication. For the research of same area ratio different shapes, it can be obtained that with 3/4 ring road,3/4 affirmative ring road, triangular, pentagonal, V-shaped and fan-shaped texture surface shape can have a better lubricating effect, and the texture depth is smaller, the lubricating effect is better. For the same surface shape texture, change texture size parameters can also change the texture lubricating effect, for the triangle under the same area condition, the effect that bottom is less than high is better than the bottom is greater than high (when the moving direction of the upper wall is from the bottom to the high). When the texture is partial texture, the effect is better than un-partial texture. For humanoid groove, the larger the inclination angle, the better the lubricating effect when the width of both sides and the top are determined. In the same area of occupancy, the greater width of both sides have, the better lubrication effect is.Secondly, studied the surface texture lubrication conditions under plane rotary motion and spiral movement. Studies have found that under the plane rotary motion, the indentation in the study of texture, under different area share S and texture depth h, compared with rectangular, ellipse and circle,the hydrodynamic lubrication effect of isosceles triangle, right triangle (right angle near the inner ring), right triangle (right angle near the outer ring), v-shaped, pentagon is better. This is consistent with the results of the plane liner movement, it can be concluded that the conclusions drawn from the plane liner motion are also applicable to plane rotary motion. Under the plane rotary motion, the groove texture in the study, compared with humanoid groove, the texture of spiral groove, triangular groove, straight groove on the surface dimensionless pressure value is bigger, the hydrodynamic lubrication performance of spiral groove, triangle groove and straight groove is better than that of humanoid groove. Whether spiral groove, triangle groove or humanoid groove, when the width of the entrance pressure is larger, the wall on the dimensionless pressure value is bigger. Under the plane rotary motion, the grooves on the texture of wall dimensionless average pressure is bigger than the value of texture in the pits.Thirdly, through the ring-ring friction experiment to study the various texture under the same load and speed of the friction and wear. Examining various texture shape and area ratio under the size of the friction coefficient and wear rate, verify the validity and feasibility of the simulation, thus, the numerical simulation in FLUENT is of certain significance and guidance on surface texture technology.Finally, extending from plane to the spiral surface of screw nut contact. For helical motion under the influence of pits and grooves, the S=5%, when the initial film thickness h=0.0065 mm, in the seven kinds studied texture, compared with the rectangular texture, oval texture and round texture, triangle texture and pentagon texture have good lubrication performance. In the same 3 textures of triangle texture, compared with isosceles triangle and right triangle (right angle near the outer ring), the hydrodynamic lubrication effect of right triangle (right angle near the inner ring) is better, that is, along the direction of the movement, the hydrodynamic lubrication effect can be generated better when the right angle is close to the inner ring. The above law is consistent with the numerical simulation law of the plane rotation movement, the rules can be inferred in plane rotation that is applied to the helical motion.