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| A Method for Calculating the Dislocation Contrast Factor in X-ray Diffraction Profile Analysis |
| HU Qiu-shi,ZHAO Feng,FU Hua |
| Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan 621900, China |
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Abstract The displacement field produced by dislocations was calculated by using Teodosiu anisotropic elastic theory.The formulas for calculating the dislocation contrast factors of different slip systems were established.Taking the cubic crystal as example, the calculation process was simplified, and the contrast factors of dislocations distributed in 12 slip systems under 8 diffraction indices in f.c.c Cu and b.c.c Fe were given.The calculation results were compared with those in the literature.X-ray diffraction experiments were carried out on oxygen free copper subjected to different quasi-static compression loading strains.The role of the contrast factor in eliminating the anisotropy broadening of the diffraction profiles was described.The subgrain size, screw dislocation ratio and the dislocation density in the sample were obtained by using line profile analysis.
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Received: 16 August 2017
Published: 05 September 2018
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2018, Vol. 39 
