摘要
对分别在1 600℃、1 650℃、1 700℃条件下热压烧结制备的Si2N2O-Si3N4超细晶陶瓷进行纳米压痕试验测试,获得了材料的硬度值、弹性模量值和载荷-深度曲线。考虑试验中波士压针的磨损缺陷,通过理论和数值模拟相结合的方法,确定压针的尖端球面半径RBerk=500nm。以纳米压痕试验数据为依据,利用MSC.Marc有限元仿真软件模拟纳米压痕试验压针压入材料表面的过程,反推出所测试材料的应力应变关系曲线,其屈服应力随弹性模量的减小而降低,分别为47GPa、43GPa、35GPa。通过比较分析压痕区域的应变场和应力场,分析纳米压痕试验中材料的变形特征。
The hardness ,the elastic modulus and the load-depth curves of the ultrafine-grained Si2N2O-Si3N4 composites ,which are fabricated by hot-press sintering at 1600℃ ,1650℃ ,and 1700℃ ,are tested by nanoindentation .The imperfection of Berkov-ich indenter used in the nanoindentation test is considered ,and its tip radius ,RBerk =500 nm ,is determined by theoretical calcula-tion and numerical simulation .The processes of nanoindentation are simulated by finite element software MSC.MARC based on the nanoindentation experimental date .The stress-strain curves are derived through comparative analysis between simulation re-sults and experiment results .The yield stress of the materials tested by the nanoindentation increases with the increasing of the e-lastic modulus ,with corresponding values of 47 GPa ,43 GPa and 35 GPa .The deformation behaviour of the nanoindentation is further studied through comparative analysis of strain and stress distributions .
出处
《塑性工程学报》
CAS
CSCD
北大核心
2014年第5期127-132,共6页
Journal of Plasticity Engineering
基金
河北省自然科学基金资助项目(E2012203086)
