Effect of beam divergence on the accuracy of experimental-analytical determination of thickness of layer analysed in X-ray radiographic testing of objects by sliding beam

The effect of beam divergence ω on the accuracy of determination of thickness t of material layer participating in creating the deffraction image is analyzed. The error in determining the Δt/t thickness related to ω is proportional to ω/α (α-beam slope angle to sample plane). At α=PHIsub(m)+ω/2 (PHOsub(m)-angle of total external reflection) Δt/t >100%. When α 100%. When αTHETA (THETA-slide angle), Δt/t <= 5%. At α=90 deg Δt/t < 1%. Taking armko-iron as an example shown is the possibility of ω selection ensuring the determination of absolute value t in case of readiography of the ob ect with diffractometers by sliding beam with an error not exceeding 10%. The results obtained are required for nondestructive X-ray in layers analysis of substances