Study On The Effect Of Alloying Treatment On Wear Resistance Of High Manganese Steel Liner

Ball mill is an important crushing equipment used in mineral processing,building materials and other industries,while liner is the core component of ball mill,its main failure form is wear.High manganese steel,as an excellent wear-resistant material,is often used to make ball mill liners.With the development of large-scale and high-efficiency ball mill,the service condition of liner is more and more severe,and the ordinary high manganese steel liner cannot meet the requirement of use.For a long time,high manganese steel has been widely used,mainly because of its good toughness and the work hardening capacity under strong impact load conditions,which makes it exhibit good wear resistance,but when the impact of high manganese steel is small,its work hardening effect is insufficient and the wear resistance is poor.In this paper,the high manganese steel is alloyed by V,Ti single element alloying scheme and V-Ti,V-Ti-RE multi-element alloying scheme respectively.Then,the micro analysis and performance test of high manganese steel are carried out by means of metallographic microscope,scanning electron microscope,hardness testing machine,tensile testing machine and friction-wear testing machine.The effects of different alloy types and contents on the structure and properties of high-manganese steels are studied;the mechanism of the action of alloying elements is explored;and the optimal content of the elements that significantly increased the wear resistance of high-manganese steels is determined.The conclusions are as follows:(1)In this study,the transformation of austenite to pearlite occurred in the structure of high manganese steel after water toughness treatment.There are more pearlite in ordinary high manganese steel,while less in alloyed high manganese steel,which is basically a single austenite structure.After V and Ti alloying treatment,the amount of alloy precipitates in high manganese steel is increased compared with that in ordinary high manganese steel,the grains are obviously refined and the distribution is more uniform;the inclusion size is reduced,the shape and distribution state are improved.After adding rare earth elements,the number of inclusions decreased.(2)After the alloying treatment,the hardness of the high manganese steel is greatly improved,the strength is not significantly improved,and even decreased,but it meets the expected requirements.Among them,the hardness and strength of V-alloyed high manganese steel have been improved,and both of them improve with the increase of V content;The hardness of high manganese steel has been significantly improved by Ti alloyed treatment,but the strength has not been increased,and decreases with the increase of Ti content;By V-Ti alloyed,the hardness of high manganese steel has been improved,and its strength increases with the increase of alloy content.In V-Ti-RE alloy scheme,the hardness of the alloy sample is higher than that of the ordinary samples,but the strength of the sample is relatively low.(3)Part of the alloy elements are solid-dissolved in the matrix,which improves the hardness of the high-manganese steel matrix,and some alloy elements are precipitated in the form of the second phase,thereby refining the grains,enhancing the work hardening ability of high manganese steel and increasing the grinding surface hardness after deformation.Reduce the size and quantity of inclusions,improve their shape and distribution,so as to reduce the harm of exfoliation wear;A large number of diffused hard points are added to protect the matrix,thus making the high manganese steel more wear-resistant.Compared with ordinary high manganese steel,the wear rate of V alloyed high manganese steel is reduced by 5.6%?27.8%;The Ti alloying reduces the wear rate by47.2%?61.1%;The V-Ti alloying scheme reduces the wear rate of high manganese steel by2.8%?44%;In the V-Ti-RE alloying scheme,the wear rate is reduced by 13.8%?33.3%.(4)By comparing the properties of single element alloying sample with multi-element alloying sample,it is found that the single element alloying treatment with only vanadium or titanium can improve the properties of high manganese steel more significantly.When Ti element is added separately and the content is 0.0073%,the wear resistance of high manganese steel is the best,and this scheme has less alloy addition and low production cost,which is more suitable for practical production.