Friction And Wear Behavior Of Bionic Coupling Grey Cast Iron Processed By Laser

The arrester is a key component to ensure brake performance and conveyance safety. As road construction changes with each passing day, the running speed of the car is gradually increasing. In the course of conveyance tool′s developing towards high speed, the present brake performance and lifespan of the arrester can not satisfy the high speed requirement of the car. It is imperative to develop a new type of arrester with long lifespan and high efficiency.Nowadays, one third to one half of utilized energy in the world is consumed in the form of friction. To prolong the lifespan of mechanical accessory has great economic significance. As friction wear is one of the key causes for the failure of mechanical equipment, half of the GDP in developed countries is used to change the waste products caused by friction wear and similar things. Thus, many developed countries in the world are actively engaged in the research and application of tribology.As for arrester, friction and wear are two either relevant or contradictory aspects in the course of glide. There is a need for certain friction resistance but not too much wear. It is one of the concerned subjects to improve the friction coefficient and at the same time to prolong the lifespan of arrester. Organism configuration becomes faultless by means of the optimization of 20 hundred million years. We find that the surface of organism is non-smooth, wearproof, anti-extrusion, anti-crack, through the study in such animals as dung beetle, pangolin, razorshell, etc. Motivated by the surface features and composition mechanism of organism, we form and manufacture a new type of coupling material which has a good wearability and low cost according to model biology.This disserfation is concerned with how to improve the wearability and to prolong the lifespan of auto arrester. We design and treat the surface of arrester by applying model biology coupling principle and lazer machining technology.Various surface forms can be completed by means of the combination of non-smooth units with concave, stria, and grid style. To get a good wearability of coupling arrester material, we make the orthogonal design by using lazer-processed electric current, pulse width, and workbench speed as the variables and see the influence of various factors on bionic non-smooth units. By analyzing the various coupling factors'influence on wear performance in the condition of natural temperature and high temperature, we find the law of coupling factors'influence on arrester's wearability. At last, we devise a lazer bionic coupling equipment system. Our conclusions are as follows:(1) Bionic non-smoth units of different organizations and original can be shape on the surface materials with the help of the laser.Seen from the surface; they show forms of concave, stria and grid. Seen from the section, they are embedded in the tissues of surface with deep U and shallow U. They can simulate different organic surface forms by coupling.(2) The organization structure of bionic non-smooth units is made up of melting solidity region and phase change region formed by laser processing. Melting solidity region is made up of ledeburite organization and metastable phase. Martensite takes the place of pearlite in carbide because the cooling speed of ledeburite is high. The organization of phase change is martensite+graphite.(3) The form, section area, hardnessand cracktrend of bionic non-smooth units change with laser parameters. As laser electric current, pulse width increase, the section area, hardness and crack of bionic non-smooth units increase. Non-smooth units show shallow U and section area becomes small and hardness and crack trends reduce.(4) In the condition of natural temperature, the wear resistance and friction coefficient of bionic non-smooth casting material by the laser processing increase by a wide margin than the same smooth surface material. When the shape, size, annexation of inset surface, organization, hardness are different, the wear resistance of bionic non-smooth coupling casting material is different. When the thickness and hardness are greater and the diameter is bigger and the interval is smaller, the wear resistance is better and the friction coefficient is higher. When the above factors remain the same, the wear resistance and friction coefficient of bionic non-smooth surface samples are concerned, grid is first ,stria is second and concave is third.(5) The reasons why wear resistance is improved are that the bionic non-smooth unit materials of high strength and hardness bulge the surface and form non-smooth shape. Their friction surface contact with friction pairs is equal to increasing many strength material points and decreasing the contact area with friction pairs. It resists wear and supports pairs. Its wear mechanism is that the friction surface of unit is worn first, and then, when the surface is smooth, the bionic non-smooth unit and original body are worn together. The unit of original body appears because of the hardness and strength of original body is lower than bionic non-smooth units. And the friction surface wear is formed. The procedure is continually repeated. (6) The reason why friction coefficient increases is increase of friction resistance which occurs under pressure when the bionic non-smooth units thrust friction pairs to occlusion.(7) Under high temperature the bionic non-smooth casting materials have better wear resistance and higher friction coefficience than smooth surface samples. The wear resistance improves twice and the friction coefficient improves one time. The wear resistance and friction coefficient decrease when temperature increases. The fluctuation is small when temperature lowers. And the fluctuation is big when temperature is higher. At the same time the sudden change of temperature exists. It has to do with the softening of material in high temperature. It can improve softening ability in high temperature, wear resistance, friction coefficient and sudden change temperature. The joining form, size, hardness and interval all affect sudden changing temperature.(8) When the joint shape of inset surface of bionic non-smooth units is different, the wear resistance and friction coefficient in high temperature are also different. It is on the basis of arrangement of gird, stria and concave, that wear resistance becomes better or worse, friction coefficient and sudden changing temperature become higher or lower. The hardness is higher of bionic non-smooth unit. The higher the hardness of bionic non-smooth units are, the better the wear resistance is and the higher the friction coefficient and sudden changing temperature are.(9) The diameter increase of bionic non-smooth units makes the wear resistance and friction coefficient increase the interval increase of bionic non-smooth units makes the wear resistance and friction coefficient decrease. The angle between arrange direction and friction direction difference. The wear resistance is best and the friction coefficient is highest when the angle between bionic non-smooth unit arrangement and friction direction is 45o.(10) According to the characteristics and requirements of lazer processing, we have designed 2+2 dimension numerical control workbench of laser bionic coupling equipment system. It can better finish the component of laser bionic coupling equipment. Its advantages are high degree of accuracy, quick programming speed, and great convenience.(11) The numerical control workbench can be controlled in the same pace as the laser of test date majorization. Every technological parameter can satisfy the expected effect.(12) The arrester processed by bionic coupling has reached excellent effect. The service life improves 50% than normal arrester (five months). The longest service life improves more than 120%.