Effect Of Chemical Composition And Heat Treatment On The Properties Of New Material

As the main equipment for the underground transportation,the reliability of scraper conveyor determines the effic iency of coal production.The central groove edge is one of important components of scraper conveyor,its quality will affect scraper conveyor operation and coal mine's normal safety in production,so people pay close attention to it.To solve the problem of poor plastic ity and the lack of wear resistance of central groove material,a series of experiments were carried out.Based on the 20 SiMn steel,we make some work on the fine-tuning of the ingredients : reducing carbon content,adding microalloying elements,and obtain three kinds of materials.We conducted a series of quenching processing on the three kinds of materials,to obtain more stable operation of slot materials.In this paper,a series of tests on the mechanical properties and wear resistance of the material were carried out:(1)The strength and toughness of 20 CrSiMnTiMo Nb have been greatly improved.Among them,when the heat treatment process is 1200?+840?+550?,the yield strength of material reached 832 MPa,the tensile strength reached 973 MPa,elongation rate reached 23%,percent reduction in area reached 50%,the hardness reached 268.5HB,the impact energy reached 162 J.When compared with 20 CrSiMn Mo,its yield strength increased by 145 MPa,tensile strength increased by 82 MPa,elongation increased by 5.5%,the hardness increased by 52.5HB,impact energy increased by 61 J,and it can be seen that adding microalloy elements is beneficial to improve the properties of steel.(2)20CrSiMnMo B also changed,but the optimization effect is not as good as 20 CrSiMnTiMo Nb.When Compared to 20 CrSiMn Mo,its yield strength decreased 102 MPa,the elongation increased by 1.5%,the hardness increased by 7HB,the impact energy reduced 8J.Adding the alloy element Boron leads to the coarsening of grains.(3)With the increasing of the temperature of the Intercritical Quenchning Process,the ferrite content of three kinds of materials decreased gradually.When the heat treatment process is 1200?+880?+550?,the microstructure of materials is tempered sorbite.(4)The wear volume and wear rate of 20 CrSiMnTiMo Nb increased at first and then decreased,and when the quenching temperature is 840?,the wear volume and wear reached minimum;When the quenching temperature changed,the wear volume and wear rate of 20 CrSiMn Mo changed little;The wear volume and wear rate of 20 CrSiMnMo B decreased when the intercritical quenching temperature increase.And when the quenching temperature reached 880?,the best wear resistance was achieved.Aiming at the impact the quality of central groove edge,two important factors-chemical composition and heat treatment on the mechanics properties and the wear res istance of steels were studied.Optimizing chemical composition ratio and heat treatment process can further improve the quality of the central groove edge.