Modélisation numérique du billage ultrasonore

© Areva

Figure 1: Experimental USP device [6].

Figure 2: USP principle.

Figure 3: Effect on surface.

Figure 4: Fixation system of the specimen by bolts and expected residual stress profile due to USP treatment.

Figure 5: Formation of arc height due to USP treatment.

Figure 6: Specimens treated with different exposure times (the specimens are initially painted before the USP treatment).

Figure 7: Example of contact validation.

Figure 8: Evolution of restitution coefficient on the part.

Figure 9: Evolution of restitution coefficient on the bead.

Figure 10: Evolution of contact radius with the speed.

Figure 12: Numerical distribution of impacts.

Figure 13: Evolution of the average speed.

Figure 14: Distribution of normal contact speed.

Figure 15: Evolution of coverage.

Figure 16: Evolution of the average speed.

Figure 17: Distribution of normal speed at contact.

Figure 18: Deformation of a representative zone after Finite Element simulation of the impact history.

Figure 19: Maximum strain rate [s-1] during a normal impact (initial velocity = 4 m/s, ball diameter = 4 mm).

Figure 20: Local representative area and sequence of impacts (the pattern presents a 100% peening coverage).

Figure 21: Benchmark results: residual surface displacement as a function of the radial coordinate x, normalized by the maximum contact radius a*.

Figure 22: Benchmark results: accumulated plastic strain at the centre of the impact as a function of the depth z, normalized by the maximal contact radius a*.

Figure 23: Transfer of the averaged inelastic strain tensor from the SA model to the FE model

Figure 24: Almen-type experimental results for initial velocity = 4 m/s. Comparison of simulated and XRD determined residual stresses for T = 100% (a), T = 150% (b) and T = 200% (c).