Effect Of Ti, V, N On Microstructure And Properties Of Fe-Cr-C Based Wear Resistant Material

The rapid development of industry has made a higher requirements for wear-resistant materials.This project is based on the traditional Fe-Cr-C alloy system and prepared multiple composite reinforced wear-resistant hardfacing flux-cored wire with Fe-Cr-C-N-Ti,Fe-Cr-C-N-V,Fe-Cr-C-N-Ti-V three kinds of alloy system.Three types of hardfacing surfacing flux cored wires were prepared by the self-protecting open arc welding.The type and distribution of hard phases in the surfacing layer were discussed.And the influence of the change of element content on the microstructure and wear resistance of the surfacing layer were analyzed.In the Fe-Cr-C-N-Ti alloy,the content of N and other elements was first determined to be constant.The effect of Ti content on the microstructure and wear resistance of the weld overlay was studied based on it.With the addition of boron,the microstructure changes from M₇C₃,TiC and TiN.For those dispersed hard phase,the shape of cell crystal,granular is respectively observed.The results of abrasion test indicate that a quantity of Ti improve the abrasion resistance of Fe-Cr-C-N-Ti hardfacing alloys and their abrasion resistance is determined by the size,the distribution and the quantity of Ti.After confirming the quantity of Ti element,studying the affection of N element's changement for microscopic structure of surface layer and abrasion performance.The increasing of hard phase such as TiN and M₇C₃in the microscopic structure.With the increase of N content,the hardness of the surfacing layer gradually increases,and the wear resistance increases first and then decreases.It was finally determined that when the Ti content was 1.28wt.%and the N content was 0.11wt.%,the comprehensive performance of the surfacing layer is the best.In the Fe-Cr-C-N-V surfacing alloy,the microstructure is matrix phase?-Fe,M₇C₃,VC and VN.The hard phases such as M₇C₃,VC,and VN are distributed in matrix with regular four-sided rows.The results of abrasion test indicate that VN,VN and M₇C₃ hard phase significantly improve the abrasion resistance of Fe-Cr-C-N-V hardfacing alloys.Adjusting N element's quantity after confirming V element's quantity,studying N element's affection for microscopic structure and function.VN and M₇C₃ quantity increase as N element's increasing,grain size will be bigger during VN size's increasing,then the stress concentration in the grain will lead to surface layer harness decreasing.The abrasion performance testing result shows that the surfacing layer abrasion performance will decrease with the increase of N content.Finally it can be confirmed that when the V content was1.14wt.%and the N content was 0.11wt.%,the comprehensive performance of the surfacing layer is the best.In the Fe-Cr-C-N-Ti-V surfacing alloy?Ti,V?N and?Ti,V?C are synthesized in situ.With the increase of V content,the number of hard phase in the microstructure gradually increased.The results of abrasion test indicate that the hard phase will increase with the V element's increasing,while the abrasion performance will increase.Finally it can be confirmed that when the Ti content was 1.28wt.%,the N content was 0.11wt.%and the V content was 2.44wt.%,the comprehensive performance of the surfacing layer is the best.