TA18, a kind of titanium alloys with the nominal chemical composition of Ti-3Al-2.5V and great comprehensive properties, had been developed successfully by American scientists. TA18 tubes have been used widely for the hydraulic pipe system of commercial aircrafts, chemical engineering equipment etc. Till now, TA18 tubes have been produced by cold rolling, which process has a significant impact on the properties, especially on the distribution of texture. So the systemic research on this process has important value in theory research and practical application. The whole deformation process of TA18 tubes of three-roller cold rolling was researched systematically and thoroughly in this thesis.
(1) Based on the bracket design theory, the bracket software was developed with Matlab and VB. According to the selected design method, the relevant bracket working curve can be computed by using this software. The parametric finite element modeling can be established by combining with the relevant Python script code.
(2) In order to improve the accuracy of the finite element analysis of three-roller cold rolling, the material mechanical property has been measured and analyzed and TA18 material database was developed based on MSC.Marc.
(3) According to the analysis of FE simulation, the characteristic of three-roller cold rolling was particularly summarized. The contact rule between the groove and the tube was obtained. The trajectory of a material point in the rolled tube was analyzed. The relationship between friction and shear stress was discussed. The distribution of axial force was also analyzed. The tube torsion deformation was revealed and the relationship between the torsion angle and the processing parameters was also deduced. At last the deformation mechanism at different stages was analyzed in detail.
(4) Based on the empirical equation between Kearns factor and parameter R in the ideal texture modeling, the texture prediction modeling was built, and the relevant subroutine was also established and integrated into the finite element software MSC.Marc. The distribution of TA18 tube texture in the whole transition zone was analyzed. It was found that the length ratio between the diameter-reduced zone and the thickness-reduced zone has little influence on the texture of final tubes. The relationship between Q and Kearns factor (texture) was acquired by FE simulation.
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