Modelling the Fracture Toughness of Cemented Carbides Using an Energy Release Rate Approach
Fracture in composite materials are governed by different fracture mechanisms depending on the properties,volume fraction and distribution of the constituent phases.In cemented carbides the main fracture mechanisms are interand transgranular carbide fracture,carbide/binder interface decohesion and ductile tearing of the binder.Using an energy-release rate based approach the composite fracture toughness is modeled based on the fracture energies associated with these four fracture mechanisms.The sub-models for the different mechanisms are based on experimental data and theoretical calculations in the form of finite element simulations and density functional theory calculations.The transand intergranular carbide fractures are treated as ideal-elastic using the Griffith criterion,whereas the confined ductile fracture of the binder and plastic deformation around the carbide/binder interface fracture are treated by finite element simulations.Furthermore,the fracture path is empirically modelled based on available literature data.All sub-models are then combined into a single fracture toughness model for WC-Co cemented carbides that shows good agreement with experimental data even before optimization by introducing fitting parameters.The present modelling approach should thus form a promising model platform for conventional WC-Co based cemented carbides but,due to its mechanistic basis,may also be extended to alternative binder systems.
Fracture toughness Energy release rate Cemented carbide Finite element method Materials Design
Linder David Walbrühl Martin Yan Jiayi (A)gren John Borgenstam Annika
KTH Department of Materials Science and Engineering,100 44 Stockholm,Sweden KTH Department of Materials Science and Engineering,100 44 Stockholm,Sweden;QuesTek Europe AB,Stockh Thermo-Calc Software AB,Stockholm,Sweden
国际会议
北京
英文
765-769
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）