采用球形压头的数值模拟表明,当应变硬化指数n大于0.23时,不论屈服应变σy/E为何值,在压入过程中所有材料的压痕周围均出现凹陷;当n小于0.23时,随着σy/E的增大,材料由凸起向凹陷转变;当σy/E大于0.02时,不论n为何值材料也都出现凹陷;当σ y/E小于0.02时,材料出现凸起向凹陷的转变,当比值残余压痕深度/最大压入深度(hf/hmax)小于0.76时,材料出现凹陷,n值越大凹陷越严重;当hf,/hmax>0.76,若n<0.23材料出现由凸起向凹陷转变,若n>0.23材料均发生凹陷,还得到了反映凸起凹陷的表观参量C2与接触面积Am之间的函数关系,分析了C2对压痕硬度误差的影响规律.
参考文献
[1] | X.Hernot,O.Bartier,Y.Bekouche,EI.R.Abdi,Influence of penetration depth and mechanical properties on contact radius determination for spherical indentation,International Journal of Solids and Structures,43,4136(2006) |
[2] | G.Das,S.Ghosh,S.C.Bose,S.Ghosh,Use of ball indentation technique to evaluate room temperature mechanical properties of a gas turbine blade,Materials Science and Engineering,424(A),330(2006) |
[3] | M.Dao,N.Chollacoop,K.J.Van Vliet,T.A.Venkatesh,S.Suresh,Computational modeling of the forward and reverse problems in instrumented sharp indentation,Acta Mater.,49,3899(2001) |
[4] | Y.P.Cao,J.Lu,A new method to extract the plastic properties of metal materials from an instrumented spherical indentation loading curve,Acta Materialia,52,4023(2004) |
[5] | D.Tabor,The Hardness of Metals (Oxford,University Press,1951) p.14 |
[6] | Y.T.Cheng,C.M.Cheng,What is indentation hardness,Surface and Coatings Technology,133-134,417(2000) |
[7] | A.Bolshakov,G.M.Pharr,Influences of pile-up on the measurement of mechanical properties by load and depth sensing indentation techniques,J.Mater.Res.,13,1049(1998) |
[8] | Y.T.Cheng,C.M.Cheng,Scaling approach to conial indentation in elastic-plastic solids with work hardening,J Appl.Phys.,84,1284(1998) |
[9] | W.C.Oliver,G.M.Pharr,An Improved technique for determining hardness and elastic modulus using load and displacement indentation experiments,J.Mater.Res.,7(6)1564(1992) |
[10] | H.L.Lee,J.H.Lee,G.M.Pharr,A numerical approach to spherical indentation techniques for material property evaluation,Journal of the Mechanics and Physics of Solids,53,2046(2005) |
[11] | N.W.Chollacoop,Computational and experimental study of instrumented indentation,PhD Thesis,Massachusetts Institute of Technology (2004) |
[12] | J.Alcala,A.C.Barone,M.Anglada,The influence of plastic hardening on surface deformation modes around Vickers and spherical indents,Acta Mater.,48,3451(2000) |
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