The Building Of Parameterized Model Of Microstructure Of WC-Co Cemented Carbide And The Research Of Its Property

The current researches of cemented carbides of the world are mostly based on the traditional way of experiments,and the real experiments which cost lots of human and materials resources,and it’s hard to get the accurate influence of the microstructure to the macroscopic properties of mateials as the complexity of material itself.By using some kinds of algorithms to build the parameterized model of microstructure of material and combined with the finite element method to do the mechanical property simulation,which can effectively realize the optimization of property of material, the saving of materials cost and the reducing of material development cycle.Based on the real microstructure of WC-Co cemented carbides,a method which was self adaptive to build microstructure parameterized model of two dimensional was developed. The WC average grain size and its distribution,major axis and minor axis,orientation angle,centroid and the content of Co of the real mocrostructure of WC-Co were measured.Including the WC grain major axis and minor axis were according to the “ellipse equivalent” and “rectangular equivalent”which were putted forward as a method measured.Then based on the secondary development of Auto CAD,the statiscal experimental values should be inputted to the parameterized model and WC grains were generated in the parameterzed model.Therefore the parameterized model was built to reflect the real microstructure.The results showed that the microstructure parameterized designed values matched well with the experimental measured values,so the parameterized model has been confirmed to be reliable.Based on the self-adaption parameterized modeling method,the parameterized model of microstructure of WC-Co cemented carbides of the different content of Co have been built. And the finite element model of two-dimension microstructural of WC-Co cemented carbide has been built to research the influence of different Co volume content to the mechanical property of WC-Co cemented carbides and to do the analysis of the defomation mechanism of microstructure.The results showed that the more lower of the content of Co the more higher strength of the cemented carbides,and the inner stress focused on the WC and WC interface.Based on the self-adaption parameterized modeling method, the two different WC average grain size of nanometer grain and submicron grain of different distribution variance of the parameterized model of microstruature of WC-Co cemented carbides have been built. And the finite element model of microstructural of WC-Co cemented carbide have been built to research the influence of WC average grain size and the different distribution variance.The results showed that without conserving the influence of grain interface and grain size scale the change of the different distribution variance influenced a little to the mechanical property to the nanometer grain;and the more lower of the distribution variance the more strength of the mechanical property to the submicron grain;and the grain size with a certain range influence a little of the mechanical properties of the alloy.Based on the self-adaption parameterized modeling method,the parameterized model of the different gradient layers which are of different Co volume content of microstructure of WC-Co cemented carbides of the Ti C coating gradient structure have been built. And the finite element model of microstructural of WC-Co cemented carbide has been built to predict the thermal residual stress.And the reaearch of the influence of without gradient structure and the change of the content Co of gradient layer to the thermal residual stress which include the radial stress,shear stress and the Mises equivalent stress.The results showed that the rich content of Co help to reduce the value of thermal residual stress,but the content of Co of the gradient layer is not the higher the better.