After that, only heat treatment and cutting are performed. Forging temperature and deformation degree are the basic factors that determine the microstructure and properties of the alloy. The heat treatment of titanium bar is different from that of steel. Die forging is usually used to make the shape and size close to the scrap. It has no decisive effect on the alloy structure. Therefore, the process specification of the post process of titanium bar Z has a particularly important role. The overall deformation of the blank shall not be less than 30%, and the deformation temperature shall not exceed the transformation temperature. In order to make the titanium rod obtain high strength and plasticity at the same time, the temperature and deformation degree shall be distributed evenly throughout the deformed blank as far as possible.

After recrystallization heat treatment, titanium bar and property uniformity are not as good as steel forgings. In the region of intense metal flow, the low magnification is fuzzy crystal, and the high magnification is equiaxed fine crystal; In the difficult deformation area, due to the small deformation or no deformation, the organization often keeps the state before deformation. Therefore, when forging some important titanium rod parts (such as compressor disk, blade, etc.), in addition to controlling the deformation temperature below TB and the appropriate deformation level, it is very important to control the structure of the original blank. Otherwise, the coarse grain structure or some defects will be inherited into the forging, and the subsequent heat treatment cannot be eliminated, which will lead to the scrapping of the forging.

When forging titanium bar forgings with complex shape on hammer in the sharp deformation area where the thermal effect is concentrated locally. Even if the heating temperature is strictly controlled, the temperature of the metal may still exceed the TB of the alloy. For example, when forging the titanium bar blank with I-shaped cross section, the hammering is too heavy, and the local temperature in the middle (web area) is about 100 ℃ higher than the local temperature at the edge due to the deformation heat effect. In addition, the hard deformation zone and the zone with critical deformation level are prone to form coarse grain structure with low plasticity and durability during heating after die forging. Therefore, the mechanical properties of forging with complex shape on hammer are often unstable. However, it will lead to a sharp increase in the deformation resistance. Although reducing the die forging heating temperature can eliminate the danger of local overheating of the blank. Increase tool wear and power consumption, and use more powerful equipment.

The local overheating of the blank can also be reduced by using the method of multiple taps. However, it is necessary to increase the heating times for hammer forging. To compensate for the heat loss caused by the contact between the blank and the cooler mold. Forgings with simple die forging shape when the requirements for plasticity and durability strength of deformed metal are not too high. Hammer forging is preferred. but β Hammer forging is not suitable for the alloy, because repeated heating during die forging will have a beneficial effect on the mechanical properties. Compared with the forging hammer, the working speed of the press (hydraulic press, etc.) is greatly reduced, which can reduce the deformation resistance and deformation heat effect of the alloy. When titanium bars are forged on the hydraulic press, the unit forging force of the blank is about 30% lower than that of the hammer forging, which can improve the service life of the die. The reduction of thermal effect also reduces the danger of overheating and temperature rise exceeding TB.

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