Introduction
Titanium alloy forging process can be divided into two categories: cold forging and hot forging. Of these, hot forging process is adopted more widely due to its well-developed and varied techniques. Hot forging is the typical method for the manufacturing process for titanium alloy products. The most commonly used techniques are upset forging, press forging and die forging.
Definition
Hot forging is the deformation processing of metal parts by applying a large plastic deformation force at a certain temperature to improve the mechanical properties and shape of the products. The forming force is more than 30 tons, the forming temperature is higher than the recrystallization temperature but lower than the liquid temperature of the material. Hot forging is a special technique with advantages like high precision, good repeatability, forming speed and stable performance.
Objects and Components
Titanium alloy forgings are mainly used for components and parts in the aerospace industry, biochemical industry, marine engineering, automotive industry, medical devices and chemical industry. Commonly used titanium alloys for hot forging include pure titanium, titanium alloy TC4, titanium alloy TA7 and so on. The products are mainly aviation structural parts, turbine blades, wheels, engine parts, compressor parts, etc.
Process
First of all, the material preparation is completed. The raw material used for hot forging process should be annealed or solution treated in order to eliminate internal stresses, so as to obtain satisfactory mechanical properties and good surface quality. Secondly, the heated material is moved in the proper sequence and pressure is applied to get the desired shape. Thirdly, the deformed components are cooled in the air or transferred to the cold die for forming. The cooling rate should be proper to avoid the sudden lowering of temperature, which leads to cracking and hardening of the material. Lastly, the finishing is completed by machining or grinding.
Advantages
Hot forging has a wide range of objects, suitable for many alloys, complicated components and various shapes, and can meet the high dimensional accuracy requirements of many components. The parts produced by hot forging process have good compressive strength, high fatigue strength, high dimensional accuracy and good surface quality. Moreover, the hot forging process has high forming efficiency, high degree of automation and improved production capacity.
Disadvantages
Compared with cold forging process, hot forging has some disadvantages. High working temperature leads to increased risk of fire and safety problems. High energy consumption may cause environmental pollution and unnecessary costs. In addition, some difficult-forming and high-precision components can not be formed by hot forging due to the problem of large deformation force and small deformation range.
Conclusion
In summary, hot forging is an important technique for the manufacturing process of titanium alloy products. It has a wide range of objects and various advantages like high forming efficiency, high dimensional accuracy and good surface quality. However, it also has some disadvantages such as high energy consumption, increased risk of fire and safety problems. According to the specific application conditions and external conditions, it is necessary to make a comprehensive analysis and select the appropriate processing method to ensure the quality and economic benefits.
