X線応力測定の精度に関する一考察

概要

論文の詳細を見る
The accuracy of stress measurement by X-rays has recently been remarkably improved, and some studies on the accuracy of measurement are reported. In this study, for the case of the film method, several problems on the accuracy of stress measurement were investigated. First, the effect of errors in the determination of the radius of diffraction ring on the measured stress values was examined for each case of the Glocker method, Δ method and sin^2ψ method. In the Glocker method, let the error in the vertical incidence and the oblique incidence of 45° be and [numerical formula] (1) where [numerical formula], ψ =tan (π-2θ') and l_ψ, l' = radius of diffraction ring for the specimen and the standard substance, respectively. In the case of the Δ method, the erroneous stress value is expressed as [numerical formula] (2) The erroneous stress values were calculated for four possible cases of combination of the signs of e and e' by taking the values of 0, 0.03, ±0.05, ±0.09 mm for e and ±0.05, ±0.09 mm for e' in Eqs. (1) and (2). These calculations were carried out for two beams of CoKα and CrKα by selecting two arbitrary stress levels of 8 kg/mm^2 and 16 kg/mm^2 as correct values. For the sin^2ψmethod,erroneous values of cosecθ'_ψ can be calculated form the correct values of cosecθ_ψ by introducing the error e. Thus two incorrect values of cosecθ'_ψ were plotted as the ordinates of corresponding sin^2ψ, and from these points the maximum and minimum gradients were determined. For the purpose of comparison of accuracy among the three methods, the errors e of opposite signs were introduced into the two extreme cases of ψ=0° and 45° for the sin^2ψ method. Under the same values of the error as in the Glocker and Δ methods, the incorrect stresses were determined. Secondly, in the sin^2ψ method, the influence of errors in the setting angle was studied. Assuming the error in the setting angle as ±1° in each incidence and plotting the erroneous values of cosecθ'_ψ as the ordinates of corresponding correct sin^2ψ, the maximum and minimum values of σ' were calculated. Thirdly, as experimental study, the effect of several ways for the determination of the peak position of diffraction profile was investigated. In addition to the ordinary half-breadth method at half height (1/2H), those at the heights of 3/8H and 5/8H were experimented, and the accuracy was compared among these three ways. Besides, the efficacy of the separation of Kα doublet was examined.
社団法人日本材料学会の論文
1965-12-15

X線応力測定の精度に関する一考察

スポンサーリンク

概要

著者

関連論文

スポンサーリンク