Analysis Of Mechanical Properties And Frictional Wear Performance Of Magnesium Alloy Metal Belt Under The High Speed

In order to solve the problems of environmental pollution and energy shortage caused by traditional cars,China has vigorously promoted the research and development of electric vehicles.The metal belt of continuously variable transmission has good economic,dynamic and comfort advantages,which is very in line with the requirements of energy saving and environmental protection of electric vehicles.Under high speed conditions,the centrifugal force of the CVT metal belt increases,which will affect its transmission efficiency.In view of this problem,this paper proposes the method of replacing CVT metal sheet with magnesium alloy material,and studies the mechanical characteristics and wear life of CVT magnesium alloy metal belt under high speed conditions.The following work was mainly done:1. The transmission mechanism and key components of CVT are discussed,and the transmission geometry of the metal belt is derived.The influence of high speed on the centrifugal force of the metal belt is analyzed,and on the basis of considering the centrifugal force,the force analysis of the CVT metal belt is carried out,and the mechanical analysis model is established.The effects of different velocity ratios and speeds on pushing force,tension and axial forces are calculated.2. Using Solidworks software to establish a CVT 3D model,and the use of ANSYS simulation software for its simulation analysis.The effects of different speed,speed ratio and torque on the stress distribution,strain distribution and side contact stress distribution of magnesium alloy sheet are obtained by simulation,combined with the relationship between wear and stress,and the effects of different speed,velocity ratio and torque on the wear degree of magnesium alloy sheet are analyzed.3. The AZ91D magnesium alloy specimen was used for wear experiments,with the experiment to verify the magnesium alloy material wear resistance is poor characteristics.The wear type of metal sheet is analyzed,which lays the foundation for the model of the wear of the metal sheet.Based on Archard wear model,the wear model and wear life model of the metal sheet are derived,and the wear life of magnesium alloy sheet under high speed conditions is calculated.4. In order to prolong the wear life of magnesium alloy metal sheet,a thermal processing method for preparing coating made on the surface of magnesium alloy is proposed.AZ91D magnesium alloy as the substrate material,choose Al₂O₃/WC-12Co,Al₂O₃-Ti O₂ and WC-Co three composite powders as spraying materials,with plasma spraying equipment in AZ91D magnesium alloy substrate three wear-resistant coatings were prepared on the surface,and the wear resistance and hardness of the three coating samples were tested,and the experimental results showed that the hardness and wear resistance of AZ91D magnesium alloy after coating had been greatly improved.According to the wear life model,the wear life of the coated magnesium alloy sheet at high speed is calculated,and the wear life and the life of the general car are compared and analyzed with the wear life of the uncoated magnesium alloy sheet.Analysis of the mechanical properties of magnesium alloy metal band and frictional wear performance at high speed conditions.