Effects Of Particle Size,Particle Distribution And Mixture Of TiN And TiCreinforcement On The Mechanical Property Of Iron Matrix Composites

Particles reinforced metal matrix composites(PRMMCs)have excellent mechanical properties,suchas high strength,good wear resistanceand elevatedtemperature performance.Therefore,the PRMMC has a broad application prospectin the astronautic,automotive and electrical industry.The mechanical property of the PRMMC can be influenced by many factors,such as fabrication process,the propertyof the interface between particle reinforcement and the matrix and the property of the reinforced particles themselves(such as type,size,volume fraction and shape of particles).It was found that when using the mixture of two different sizes of particles as reinforcement(hybrid particle size reinforcement),the mechanical propertyof the PRMMC is significantly better than that of the corresponding single-sized particle reinforced composites.Also when using the mixture of two different types of particles as reinforcement(i.e.,hybrid particle type reinforcement),the mechanical propertyof the PRMMCs is significantly better than that of the corresponding monolithic particle reinforced composites.Based on these experimental observations,the purpose of this study is trying to explore the hybrid particle reinforcement strengthening effect through the finite element simulations.In this work,the mechanical property of the TiNp/Fe and TiCp/Fe composites have been studied using the finite element softwareANSYS.We establish a three-dimensional finite element model containing multiparticlestosimulate TiNp/Fe,(TiC+TiN)p/Fe compositesunder atensile loading condition.Firstly,the effects of size and distribution of TiN particles on the mechanical property of the TiNp/Fe composite have been investigated,followed by the effects of hybrid particle sizes and hybrid particle types reinforcement on the mechanical property of the TiNp/Fe and(TiC+TiN)p/Fe composites..To study the effect of particle size on the mechanical property on the TiNp/Fe composites,the particle sizes of 10?m,15?m and 30?m are used as reinforcement associated with its volume fraction of 15%.It shows that when theparticle size is smaller,the yield strengthof the composite is higher.When the particle size is 10?m,the yield strength of the composite increases 3.5%compared with thatof 15?m.When the particle size is 15?m,the yield strength increased only 0.9%compared with that of 30?m.That indicates that the small-sized particle cannot only bear the load,but also attribute more strengthening effect on the matrix.To study the effect of particle distribution on the mechanical property of the composite,the different distribution of the 10?m TiN particles in the TiNp/Fe composite has been investigated.It is found that the mechanical property of the composite with a uniform distribution isbetter than that with a random distribution.For the effect of hybridparticle size reinforcement,when the two different size of particles(10?m+15?m,10?m+24?m,15?m+24?m)mixed with a equal proportion,the mechanical property of the composites is between that of the corresponding single-sized particle reinforced composite,closer to that of the large-sized particle reinforced one.This indicates that the effect of hybrid particle size reinforcement on the strength improvement is harmful.When the two size of particles(10?m+15?m)mixed with unequal proportions,the higher content of the small-sized particles,the better mechanical property of the composite is.The improvement of mechanical property of the composites reinforced by two different sizes of particles with a uniform and random distribution isgreatercompared with the distribution effect of single-sized particles on the mechanical property.To study the effect of hybrid particle type reinforcement,the TiC and TiN particles are mixed in a equal proportion as reinforcement.The mechanical property of the(TiC+TiN)p/Fe composite is between that of the corresponding composite reinforced by monolithic type of particles,When the TiC and TiN particles are mixed in unequal proportions(1:1,1:3,3:1)as reinforcement,the higher content of the high elastic modulus of TiC particles,the better mechanical property of the composite.Those results from hybrid particle type reinforcement is consistent with the rule of mixture andthe experimental observations of the mechanical property of the(TiC+TiN)p/Fe composites without copper coating treatment of the particles.