Study On Sliding Wear Resistance Of Bionic Coupling Gray Cast Iron

Gray cast iron is widely used in the machine tool guideways,owing to its low melting point,good damping property, and low cost. As an important part of the machine tool, the wear resistance of gray cast iron guide way is a significant index in deciding the precision degree of lathe cutting, which affected the life of the machine. In recent years, with the development of traditional machine tool industry to the direction of high-and-mid-end, high accuracy, numerical control, heavy load, higher technical indicators requirements on guide way are put forward. The wear resistance of guide way is a problem in parallel kinematic manipulator. The major weak forms of sliding guide ways were the abrasive wear and the adhesion wear.Compared to the traditional methods to improve the wear resistance of guide ways,some bionic coupling structures were manufactured by laser melting treatment,through imitate the coupling characteristics of natural biological prototype. The wear resistance of these bionic coupling structures has been researched under dry and oil sliding conditions. The influence on wear resistance of bionic coupling samples by materials coupling units, shapes coupling units,the characteristics of striature coupling units(the area of bionic coupling units and the wear angle) was also studied. The wear mechanism of bionic coupling gray cast iron was studied. The main results are as follows:1. Under dry sliding condition, with the microhardness difference between base metal and bionic coupling unit becoming bigger, the weight loss of bionic coupling samples is first becoming smaller, then becoming bigger. When the microhardness of bionic coupling unit and wear pair was equivalent, the weight loss of bionic coupling sample is the smallest. It means the wear resistance is the best.2. Under dry sliding condition, the wear resistance of reticulation bionic coupling sample is the best. When the load and wear speed changed, the wear resistance of reticulation sample is also better than the untreated sample. Compared to the wear resistance IV of untreated sample, spot bionic coupling sample? striation bionic coupling sample can improve by 70.1%?197.2%.3. Under dry sliding condition,when the distance between two adjacent units is getting smaller, the weight loss of samples is getting smaller, the wear resistance is getting better. When the distance is the same, the wear resistance of the sample with 45°units is the best. the transverse striation bionic coupling units play a supporting role in the wear process, the relation is ratio relation between the weight loss and the area of units;the longitudinal striation bionic coupling units play an obstacle role of stopping the abrasive sliding and furrows developing;The influence of wear angle for the weight loss of samples:?m = ?m0- 0.0212 S ? Cos?- 0.0241 S ? Sin?.4. Under oil-lubrication condition, we put forward the microhardness indentation method to study the wear resistance of bionic coupling samples. In this method, the wear resistance was estimated by the change in microhardness indentation area and the weight loss which we get through the change of microhardness indentation high. The reliability of microhardness indentation method was validated by wear test under dry sliding condition.5. Under oil-lubrication condition, the wear resistance of different shapes bionic coupling samples was studied using the microhardness indentation method. It shows that the order of wear resistance is: untreated sample < spot bionic coupling sample < striation bionic coupling sample < full melted sample < reticulation bionic coupling sample.6. The wear resistance of different characteristics of striature coupling units has been studied under oil-lubrication sliding condition by microhardness indentation method. When the wear distance is 6000 m,there is a linear relationship between the weight loss and the area of the transverse striation bionic coupling units:?m = 6.18024- 0.00909 ? ran;there is a liner relationship between the weight loss and the area of the longitudinal striation bionic coupling units:?m = 6.18938- 0.00956 ? ong;there is a quantitative relationship between the weight loss and the wear angle:?m = ?m0- 0.00909 S ? Cos?- 0.00956 S ?Sin?.7.The order of wear resistance of non-uniformly distributed bionic coupling samples:noncentrosymmetrical non-uniformly distributed bionic coupling sample <centrosymmetrical non-uniformly distributed bionic coupling sample < uniformly distributed bionic coupling sample. The wear resistance of uniformly distributed sample is the best. For the uneven force condition of guideways, the non-uniformly distributed unit is beneficial to improve the wear resistance of guideways.