and Heat Treatment Process Performance
of Titanium Elbows
Titanium-based alloys, with their excellent corrosion resistance, are widely used in industries such as petroleum, chemicals, energy, and environmental protection. They are employed in the manufacture of pipelines and storage tanks for corrosive substances. Titanium elbows, as critical components connecting these pipelines and storage tanks, have drawn significant attention for their forming processes. Cold bending forming technology has become one of the most advantageous elbow forming technologies due to its high production efficiency, high material utilization, good mechanical properties of the product, and simple mold structure.This study focuses on C276 titanium-based alloys and explores heat treatment methods to improve the cold bending performance of C276 tubular billets from the perspective of improving the cold forming performance of the material. By treating tubular billets with different heat treatment parameters and testing and comparing their performance, the study aims to obtain the optimal conditioning heat treatment parameters for cold bending.
Titanium-based alloys, with their outstanding corrosion resistance, play a vital role in numerous industries such as petroleum, chemicals, energy, and environmental protection. They are commonly used in the manufacture of pipelines and storage tanks for transporting corrosive substances. Titanium elbows, as critical components connecting these pipelines and storage tanks, directly impact the safety and stable operation of the entire system.
A. Among existing elbow forming processes, the cold push bending forming process has demonstrated numerous advantages, such as high production efficiency, high material utilization, good mechanical properties of the product, and simple mold structure. Therefore, it has become a relatively advantageous elbow forming process.
However, there are also some issues with the cold bending process of titanium alloy elbows, such as cold bending cracks, which affect product quality and production efficiency. This study focuses on C276 titanium-based alloy and aims to explore heat treatment processes to improve its cold bending performance, providing theoretical support and technical guidance for the cold bending forming of titanium elbows.
Research Content and Results
Analysis of the causes cracking in cold-pushed bends made from C276 alloy
In response to cracking that occurred during the cold pushing process of titanium elbows, we conducted an in-depth analysis of the microstructure and phase composition of the cracks in the elbows. Research has found that grain boundary segregation in pipe fittings forms microcracks when subjected to tensile forces, which is the main cause of cracking in titanium alloy elbows. This discovery provides important theoretical basis for subsequent improvements to the cold bending process. Only by resolving the issue of grain boundary segregation can the risk of cold bending cracking be effectively reduced.
The Effect of Different Heat Treatment Process Parameters on the Properties of C276 Alloy
In order to improve the cold bending performance of C276 alloy, we used different heat treatment process parameters to perform heat treatment on it, and conducted detailed research on the microstructure and mechanical properties of the alloy after treatment. After extensive experimentation and comparative analysis, the optimal heat treatment process was determined to be: 1120°C × 30 minutes + 850°C × 30 minutes. After undergoing this heat treatment process, the material achieved an elongation of 66% and a yield strength of 348 MPa, indicating that it has good plastic forming properties, providing a solid material foundation for subsequent cold push bending forming.
The effect of different bending speeds on the cold bending of C276 alloy
The Effect of Different Bending Speeds on the Cold Bending of C276 Alloy Cold bending experiments were conducted on heat-treated C276 alloy using different bending speeds. The experimental results showed that the heat-treated tube blanks did not crack during the bending process, indicating that the heat treatment process effectively improved the cold bending performance of the material.
At the same time, at a bending speed of 4 mm/s, the wall thickness reduction rate of the C276 alloy was 7.5%, significantly higher than that of samples at other bending speeds. This result provides a reference for selecting an appropriate bending speed in actual production, thereby helping to improve product forming quality and production efficiency.
Conclusion
After heat treatment of C276 tubular billets using the preliminary heat treatment process route and parameters obtained in this study (1120°C × 30 minutes + 850°C × 30 minutes), cold bending tests were conducted. The results showed that there were no cracks in the titanium elbows. This indicates that the determined heat treatment process route and parameters can effectively improve the cold bending performance of C276 titanium-based alloy, providing a feasible technical solution for the cold bending forming process of titanium elbows, which has certain practical application value. In the future, we will continue to conduct in-depth research and continuously optimize process parameters to improve the forming quality and production efficiency of titanium elbows, thereby promoting the broader application of titanium-based alloys in related industries.