Mo 掺杂对铸造 Fe-2.0Cr-3.0B 合金组织 性能及三体磨粒磨损性能影响

Taking advantage of Mo doping (1.0wt.%-4.0wt.%) method, the continuous network structure of M₂B hard phases in the cast Fe-2.0Cr-3.0B alloy has been broken, and the mechanical properties and three-body abrasive wear performance of the alloy have been improved. The Fe-2.0Cr-3.0B alloy samples were obtained by using of melting and casting+heat treatment method, and the microstructures of the alloy were analyzed by means of the metallographic microscope, SEM, EDS, XRD, and other techniques, and then systematically evaluating the mechanical and three-body abrasive wear properties. The research results show that the Mo rich M₃(B, C)₂ phases will be formed after adding Mo element, which precipitating among the M₂B phases with micro and laminated structures, and effectively breaking the continuous network structure of M₂B hard phases and promoting its transformation into block or strip shapes. The fracture toughness of the alloy is increased gradually with the increase of Mo content, and when the Mo content is 4.0wt.%(4Mo specimen), the fracture toughness of the alloy is increased about 30% comparing with that of the alloy specimen with 1.0wt.% Mo. During the three-body wear process, both of the hardness and the fracture toughness of the alloys play pivotal roles, the 2Mo specimens with higher hardness exhibiting the best wear resistance properties under the condition of low load, while the 4Mo specimens with the best fracture toughness exhibiting the best wear resistance properties under the condition of high load.