Study On Magneto-magnetic Composite Strengthening Of 20CrMnTi Vehicle Gear Steel

In the automotive industry,20 CrMnTi gear steel is a commonly used material in the production of automobile gears.It has the advantages of high hardenability and low price,and plays an important role in the gear industry.In the common failure modes of gears,wear failure also accounts for a large proportion,and 20 CrMnTi gear steel is no exception.The magnetic field strengthening of metals has become a hot topic in the field of mechanical processing in recent years and has attracted more and more attention.The magnetization treatment enhances the surface wear resistance of the parts,and is not limited by the shape of the parts.The gears have a strong applicability to the parts with complicated surfaces,and the magnetized 20 CrMnTi gear steel samples have no influence on the surface morphology.It is a more attractive place for magnetization.The positional relationship between the magnetic field and the magnetization line of the 20 CrMnTi gear steel sample,the magnetization frequency and the magnetization time all have an effect on the magnetization effect.After testing,when the direction of the 20 CrMnTi gear steel sample is perpendicular to the direction of the magnetic induction line,the magnetization time is 60 s,and the magnetization frequency is 9Hz,the effect of magnetization strengthening treatment is the best,the wear amount is only 4.3 mg,and the wear rate is 0.298%.It has dropped by about50%.Laser surface quenching is a new heat treatment process that has developed rapidly in recent years and has played an important role in improving the mechanical properties of parts.It has been widely used in the field of processing and manufacturing.Through ANSYS simulation of laser surface quenching temperature field,fully understand the process of laser quenching rapid heating and rapid cooling.The effect of the light scanning speed on the model temperature is significantly different from the laser power,which not only affects the temperature at which the node reaches the highest point,but also the time at which it begins to heat up and reach the maximum temperature.As the power increases and the scanning speed decreases,the maximum temperature of the model increases and the cooling rate increases.When the laser is strengthened,the power is 300 W and the speed is 50mm/s.The hardness of20 CrMnTi gear steel increases by 7.80 HRC to 57.53 HRC,the wear is only 4.3 mg,the wear rate is 0.058%,and the surface wear resistance is best..The surface properties of 20 CrMnTi gear steel specimens strengthened by magneto-optical composites have been further improved,and the surface crack morphology is reduced during wear.Through the test,when the surface strengthening effect of 20 CrMnTi gear steel is the best,the process parameters are laser power 300 W,scanning speed 50mm/s,magnetization frequency 9Hz,magnetization time 90 s,surface wear amount 3.5mg,wear rate0.045%,surface Best wear resistance.Laser strengthening makes the surface structure of20 CrMnTi gear steel refinement obviously.Magnetic field strengthening improves the wear condition of 20 CrMnTi gear steel,and reduces the internal stress generated by laser treatment by magnetization treatment,reduces the probability of surface defects,so as to further improve the wear resistance of 20 CrMnTi gear steel.