1、 Main forging methods

Free forging

Suitable for forgings with simple shapes and low precision requirements, relying on manual operation and low material utilization.

The process has strong flexibility, but strict control of deformation and hammering frequency is required.

Forging process

Open die forging: using a die with flash grooves, controlling metal flow in stages, and removing flash edges during final forging, suitable for mass production of complex shaped forgings.

Closed die forging: no flash edge design, high material utilization, better accuracy, but strict requirements for mold strength and temperature control.

Squeezing and Rolling

The extrusion process is formed by extruding through mold holes, suitable for long strip/pipe forgings. The material has high density, but the equipment investment is large.

Rolling controls shape through continuous deformation, with high efficiency and precise adjustment of sheet/profile dimensions.

2、 Core process flow

Open forging

The initial temperature is selected to be 150-250 ℃ above the β phase transition point, and a three-stage hammering strategy of "light heavy stable" is adopted. Intermediate annealing is required when the cumulative deformation exceeds 70%.

Multi directional forging cycle improves organizational uniformity, with deformation controlled between 50% -80% per firing.

Specialized process optimization

The U-shaped titanium alloy forging adopts a "one" - shaped stepped billet design, which is bent step by step through a dedicated tire mold and punch. The cross-section of the bar is 1.1-1.25 times that of the blank shape to improve accuracy.

The right angled trapezoidal forging is optimized for deformation distribution through multiple rounds of forging, with a single deformation amount of 20% -50%.

3、 Key points of quality control

Temperature and Lubrication

The temperature fluctuation should be monitored by infrared thermal imaging throughout the process, and the final forging temperature should be higher than the critical value of β brittleness to avoid cracking.

Using graphite based lubricants to reduce mold friction, with an R-angle greater than 15mm at sharp edges to prevent stress concentration.

Organization and Defect Prevention and Control

β brittleness repairs coarse grains by controlling heating temperature and plastic deformation.

The residual casting structure needs to ensure a forging ratio of>3:1 and dynamically adjust the deformation rate during the final forging stage.

4、 Heat treatment process

Quenching and tempering

Alpha+β titanium forgings need to be preheated at 600-650 ℃ and quenched, with a tempering temperature of 400-500 ℃.

Solid solution and aging

The solid solution treatment temperature for α+β type is 980 ℃, while for β type it is treated at 775-900 ℃; The aging temperature is 480-600 ℃, and the strengthening phase is precipitated for 2-16 hours.