Microstructure And Properties Of FeCoNiCrMnTi_x High Entropy Alloy Coating Prepared By Plasma Cladding On Mn13 High Manganese Steel

The purpose of this paper is to solve the problem of poor wear resistance of high manganese steel under low stress conditions and to meet its good impact toughness under high stress impact.The exploration of plasma claddingFeCoNiCrMnTi_xhigh entropy alloy coating on the surface of high manganese steel has been carried out.After plasma cladding FeCoNiCrMnTix high entropy alloy coating on the surface of high manganese steel,and FeCoNiCrMnTix high entropy alloy coating/high manganese steel have been studied.The effect of Ti addition and aging treatment on the structure and properties of FeCoNiCrMn high-entropy alloy coatings was investigated.The results provide a reference for the subsequent preparation of high-entropy alloy wear-resistant coatings on high-manganese steel surface which can withstand high and low impact.The results show that the surface grain structure of FeCoNiCrMnTix high-entropy alloy coating is equiaxed after cladding,and a small amount of eutectic structure is formed.The middle part of the cladding layer is dendrite,and the bottom of the cladding layer contacted with the matrix is cellular crystal.After aging,the whole equiaxed crystal of the cladding layer increases,and the corresponding dendrite and cellular crystal decrease.After cladding,the phase composition of FeCoNiCrMnTix is relatively single and stable.When x=0,the phase composition of the cladding layer is composed of a single FCC phase,the main phase is Fe0.64Ni0.36.When Ti element is added,there is a BCC phase Co3Ti,and the peak value of new phase Co3Ti increases with the increase of Ti element.After aging,the phase composition of the cladding layer is not very different,the precipitates of Co3Ti increase obviously,and the peak value also increases obviously.On the whole,the hardness of each sample decreases from cladding layer to heat affected zone and then to matrix.After cladding,the hardness of the coatings decreases slightly from surface to inside,while after aging,the hardness of the coatings decreases slightly from surface to inside,and the hardness of the coatings is relatively average,and the maximum hardness of the samples before and after aging increases with the increase of Ti content.The hardness of the matrix is about 220.4 HV,and the maximum hardness of the cladding high-entropy alloy coating is 344.5 HV.The maximum hardness of FeCoNiCrMnTi0.5 high-entropy alloy coating after aging treatment is 469.7HV.Compared with the matrix,the hardness value has been greatly improved.The friction coefficient of the matrix of high manganese steel is about0.9.The wear resistance of the cladding FeCoNiCrMnTix coating increases to a certain extent.With the increase of Ti content,the wear resistance increases.The friction coefficient and wear amount of the cladding FeCoNiCrMnTix coating reach the minimum value at Ti0.5,which are 0.38 and 10.8 mg,respectively.The wear resistance of FeCoNiCrMnTix coatings after aging treatment has been greatly improved on the whole.With the increase of Ti content,the wear resistance of FeCoNiCrMnTix coatings also tends to increase.Among them,the friction coefficient and wear amount of the aged FeCoNiCrMnTix coating reached the minimum value at Ti0.5,which were 0.13 and 3.6 mg,respectively.The morphology of matrix wear marks is a large number of deep and wide sliding grooves,and the friction type is abrasive wear.The wear morphology of the coating is mainly shallow sliding groove with a small amount of particles at the sliding groove and lamellar shedding.The wear forms are adhesive wear and abrasive wear.After aging treatment,the wear morphology has been obviously improved,the number of sliding grooves has been reduced and shallower,and the abrasive particles have basically disappeared.The impact toughness of M13 high manganese steel matrix is 148.33J/cm~2by experiment.The impact toughness of the cladding sample is about 175J/cm~2,which is higher than that of the matrix.The impact toughness of specimens aged at800 degrees for 16 hours is about 155J/cm~2,which is slightly lower than that before aging,but the impact toughness of specimens aged without Ti element reaches 182J/cm~2.The fracture surfaces of high manganese steel matrix and coating after cladding contain a large number of dimples,which are ductile fracture.After aging treatment,the fracture surfaces of Ti0.5 samples contain cleavage and dimples,which are brittle fracture and ductile fracture.The fracture surfaces of other samples are composed of a large number of dimples,which are ductile fracture.As a whole,FeCoNiCrMnTi_ximproves the impact toughness of M13 high manganese steel to a great extent.