Effect Of Composition Of Pre Alloyed Powder On Microstructure And Properties Of Sintered Diamond

The prealloyed powder has the advantages of low sintering temperature,homogeneous composition and high alloying degree.It has been used more and more widely in diamond tools.There are many advantages of cobalt base on diamond in pre alloy powder,such as good wettability and so on.But cobalt is expensive and resources are scarce,so it is of great significance to study cobalt.Because of the advantages of low price and large storage of Fe,some other elements are added to the Fe based pre alloy powder to replace the cobalt base pre alloy powder,which has broad prospects and benefits.This topic mainly studies the influence of composition and proportion of pre alloyed powder on Microstructure and properties of diamond sintered body in Fe fund.The effect of Sn content on the microstructure and mechanical properties of Fe fund sintered body was studied.Through metallographic microscope,SEM,XRD and mechanical properties,study the effects of Sn content?0%,2%,4%,6%,8%,10%?on the tissue and mechanical properties of the carcass and knives.The results showed that the Sn content increased,the matrix grains were refined,and Cu_5.6Sn and FeSn appeared in the matrix.The density and hardness of matrix increased continuously due to the increase of low melting point materials.The flexural strength of the matrix,the shear strength,the bending strength of the knife head and the holding coefficient of the diamond all increase first and then decrease,and the fracture fracture has ductile fracture to brittle fracture.With the increase of Sn content,there is a serious loss of liquid phase in the matrix.When the diamond is analyzed and the content of Sn is increased to 4%,the wettability of the matrix is the best for the diamond.FeCcompound is formed at the interface between the diamond and the matrix,and the metallurgical reaction between the diamond and the matrix exists.When Sn content is increased again,there is obvious gap between diamond and interface due to the larger expansion coefficient of Sn.When the content of Sn is 4%,the comprehensive mechanical properties are the best.The effect of Ni content on the microstructure and mechanical properties of Fe fund sintered body was studied.The effects of Ni content?0%,3%,6%,9%,12%?on the tissue and mechanical properties of the carcass and knives were studied by metallographic microscope,SEM,XRD and mechanical properties.The results show that with the increase of Ni content,the grain size of the matrix is refined,and CuNi and FeNi appear.The density,hardness,flexural strength and shear strength of the matrix increased because of the control of the loss of low melting point material by Ni and the strengthening and dispersion strengthening of Ni.Because of the erosion of Ni to diamond,the bending strength and the holding coefficient of the cutter head increase first and then decrease,and the fracture is mainly ductile fracture.After the analysis of the diamond of the knife head,it is found that there is FeCcompound formation at the interface between the diamond and the matrix,and the metallurgical reaction between the diamond and the matrix is deposited.In general,when the Ni content is 9%,the comprehensive mechanical properties are the best.The influence of the proportion of pre alloyed powder on the microstructure and properties of sintered diamond was studied.3 different pre alloyed powders,C,D and E?mainly Cu,Zn,Ni,Sn?,were added to the matrix in different proportions?0%,20%,30%,40%?.The effects of the proportion of pre alloyed powder on the microstructure and properties of the diamond sintered bodies were investigated by metallographic microscope,SEM,XRD and mechanical properties.The results show that the comprehensive mechanical properties of the cutter head are the best when 20%E pre alloyed powder is added.