company news about TC4 titanium alloy bar rolling process research

Titanium alloy material is characterized by high specific strength, high flexural strength ratio, high deformation resistance, excellent process plasticity and superplasticity, and its bar products are widely used in various fields of national economy, and there are rivets connectors made of titanium alloy bars after cold heading on aviation and space planes. At present, there is a lack of analysis on the heat treatment and microstructure of small diameter titanium alloy bars (≤ Φ10mm) hot rolling and rolled bars. In order to solve this problem, the technicians carry out a high temperature compression test on TC4 alloy in Gleeble500 thermal simulator to analyze the rheological stress curve of TC4 titanium alloy at different temperatures and strain rates, so as to provide the necessary process parameters for titanium alloy bars hot rolling and to analyze the rheological stress curve of TC4 titanium alloy at different temperatures. process parameters, and the organization and properties of the rolled products were analyzed. The results of the study found that:

1, from the perspective of reducing the deformation resistance, improving the material formability and ensuring the organizational properties of the final rolling, the optimal opening rolling temperature for TC4 titanium alloy bars is 950 ℃, which is slightly lower than the phase transition temperature of TC4 titanium alloy; the optimal strain rate is 1s-1, thus ensuring that the strain and strain rate caused by strain hardening in the deformation process is small, and the plasticity of the material is brought into full play;

2. Φ12 and Φ6mm bars are obtained by hot continuous rolling in three-roll Y-type mill. Φ12mm bars are organized into equiaxed primary α phase + α strip + β transformation organization, with grain diameter of 3-10μm; Φ6mm bars are organized into a small amount of equiaxed primary α phase + fine strip α phase + β transformation organization, with grain size of not more than 1μm. it can be seen that with the increase of the cumulative deformation amount, the grain size decreases significantly;

3, three-roll Y-type mill hot rolling obtained by TC4 titanium alloy bars, its organization and mechanical properties meet the technical requirements. The rolling equipment, rolling process parameters and heat treatment system used in the test can produce titanium alloy bars that meet the requirements, thus providing a technical basis for further industrial production.