Titanium alloys are widely used in aerospace, medical, chemical, and other fields due to their high strength, low density, excellent corrosion resistance, and good biocompatibility. However, the forging process of titanium alloy process is a technically difficult process involving many challenges. This article will discuss in detail the main difficulties and solutions in forging titanium alloys.
1. Low thermal conductivity
The thermal conductivity of titanium alloys is low, only 1/7 of steel, 1/16 of aluminum, and 1/25 of copper. This means that during the forging process of titanium alloy process, heat is difficult to transfer quickly, resulting in rapid accumulation of heat in the cutting area, causing the tool and mold to be subjected to extremely high temperatures, accelerating wear and even failure. In addition, high temperatures will also destroy the surface integrity of titanium alloy parts, resulting in reduced geometric accuracy. In severe cases, work hardening may occur, which will damage its fatigue strength.
Solution:
Use high-performance tool materials, such as cemented carbide, ceramics, etc., to improve the tool's high-temperature resistance and wear resistance.
Use coolant for sufficient cooling to reduce the temperature of the cutting area and reduce heat accumulation.
Optimize the forging process of titanium alloy process parameters, such as reducing cutting speed, increasing feed rate, etc., to reduce tool wear and improve processing efficiency.
2. Low elastic modulus
The elastic modulus of titanium alloy is relatively low, and it is easy to deform elastically during the forging process of titanium alloy process, especially when processing thin-walled or annular parts. This problem is more prominent. Due to the strong plastic deformation ability of titanium alloy, when the workpiece material is subjected to external force, the local deformation may exceed the elastic range, resulting in plastic deformation. This plastic deformation will not only increase the cutting pressure and intensify the "elastic" rebound phenomenon of the workpiece but also further increase the friction between the tool and the workpiece, resulting in reduced cutting efficiency and tool life.
Solution:
Use new processing methods such as ultrasonic processing technology to reduce the contact time between the tool and the workpiece and extend the tool's life.
Optimize forging process parameters, such as reducing cutting speed, increasing feed rate, etc., to reduce tool wear and improve processing efficiency.
3. Adhesion and high-vibration characteristics
Titanium alloy has a strong affinity for cutting tools. It is easy to adhere to the cutting tools during the cutting process, forming continuous chips, interfering with the cutting process, and may cause tool damage in severe cases. In addition, the high vibration characteristics of titanium alloy processing are also a major unstable factor, which not only aggravates tool wear but also seriously affects processing accuracy and surface quality.
Solution:
Use high-performance tool materials, such as cemented carbide, ceramics, etc., to improve the high-temperature resistance and wear resistance of the tool.
Use new processing methods such as ultrasonic processing technology to reduce the contact time between the tool and the workpiece and extend the service life of the tool.
4. Details
Some details need to be paid attention to during the forging process of titanium alloy process. For example, the chemical composition and microstructure of the titanium alloy raw materials should be strictly controlled before forging to avoid defects such as inclusions and pores; the heating temperature and insulation time should be strictly controlled during the forging process to avoid overheating or overburning; heat treatment should be carried out in time after forging to eliminate residual stress and improve the mechanical properties of the material.
Solution:
Strictly control the chemical composition and microstructure of titanium alloy raw materials.
Strictly control the heating temperature and holding time to avoid overheating or overburning.
Perform heat treatment in time after forging to eliminate residual stress and improve the mechanical properties of the material.
Titanium alloy forging is a technically difficult process involving multiple difficulties such as low thermal conductivity, low elastic modulus, adhesion, and high vibration characteristics. To overcome these difficulties, the industry has explored a series of effective solutions and technical means. By adopting high-performance tool materials, optimizing forging process parameters, using coolants and new processing methods, and strictly controlling the details of the forging process of titanium alloy process, the efficiency and quality of titanium alloy forging can be effectively improved.
