GH4169晶面衍射弹性常数计算与测量

Measurement and Calculation for Crystal Plane Diffraction Elastic Constants of GH4169

摘要:

根据复相材料细观力学模型，预测了镍基高温合金等效弹性响应，基于宏观应力-应变关系，理论计算了GH4169及组分材料等效弹性性质参数，即等效弹性模量E ?，等效体积模量K ?，等效剪切模量G ?和泊松比ν ?，与文献报道的实验值对比分析，结果显示：GH4169合金理论计算值E ?=218.60GPa， K ?=180.20GPa， G ?=84.20GPa，ν ?=0.298与实验值偏差分别为7.16%、10.69%、6.58%、0.67%；γ"相理论计算值E ?=201.10GPa， K ?=173.70GPa， G ?=76.93GPa，ν ?=0.307与实验值偏差分别为1.42%、0.40%、2.00%、1.66%，较小的误差证明了该模型的准确性；进一步，理论预测了镍基高温合金细观弹性响应，基于单轴载荷作用下细观弹性应力-应变关系，理论计算了GH4169合金γ-(Ni-Cr-Fe)相(220)晶面衍射弹性常数，即E_220=233.89GPa， ν_220=0.284；同时，采用四点弯曲标定载荷应力，结合X射线衍射应变测量装置实验测量了γ-(Ni-Cr-Fe)相(220)晶面衍射弹性常数，并与理论计算值对比分析，结果表明实验测量值E_220=248.00GPa、ν_220=0.276与实验值的偏差分别为5.69%、2.90%，证实了该理论模型的准确性，也为衍射法测量残余应力研究提供理论基础。

Abstract:

According to the micromechanics of composites, the effective elastic respond of Ni-base superalloy was predicted and the parameters of effective elastic propeties of GH4169 as well as its constituent materials i.e. effective elastic modulus E ?, effective bulk modulus K ?, effective shear modulus G ? and Possion’s ratio ν ?, were also theoretically calculated on the bases of macroscopic stress-strain relationship. The results, compared with the theoretically calculation and the experimental measurement in article, are shown that the error of effective elastic property parameters of GH4169 is 7.16%、10.69%、6.58%、0.67%, respectively ; the error 1.42%、0.40%、2.00%、1.66% for γ" phase, which proves the accuracy of the theory. Furthermore, the mesomechanical elastic respond of Ni-base superalloy was predictd in theory and the diffraction elastic constants of γ-(Ni-Cr-Fe) phase of GH4169 alloy, E_220=233.89GPa, ν_220=0.284 were also calculated theoretically, based on mesomechanical stress-strain relationship of Ni-base superalloy under uniaxial loading. Simultaneously, the diffraction elastic constants of the (220) crystal plane of γ-(Ni-Cr-Fe) phase were experimentally measured with the combination of four-point bending to calibrate the load stress and X-ray diffraction for diffraction strain measurement. Contrasted between the theoretical and experimental, the results are demonstrated that the experimental E_220=248.00GPa, ν_220=0.276 and that difference between the theoretical calculation is 5.69%, 2.90% respectively, which proves the accuracy of the theoretical model and also provides a theoretical basis for the study of residual stress measurement by diffraction method as well.