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There are many factors that affect extrusion pressure, such as deformation disturbing force, deformation degree, external friction state, shape and size of die, angle of die, extrusion speed, length of ingot, section shape of product and extrusion method.

Effect of metal deformation on extrusion pressure

The change rule of extrusion pressure when different extrusion ratio and different metal and alloy are used.

The effect of extrusion on extrusion pressure

The friction effect of the metal on the contact surface of the extrusion tool (extrusion barrel, extrusion die) is the component of the extrusion pressure. The influence of surface state of different extrusion tools on extrusion pressure.

With the increase of external friction resistance of extruder, the uneven degree of metal flow increases, so the required extrusion pressure increases. The friction resistance between the metal and the inner lining of the extrusion barrel and the surface of the extrusion die increases, and the extrusion pressure increases.

Influence of die angle on extrusion pressure

The influence of die angle of extruder on extrusion pressure is mainly manifested in the deformation area and the surface of the cone in the deformation area. The relationship between extrusion stress and die angle.

With the die angle a increasing from 00, the extrusion pressure of the extruder decreases gradually. When the die angle a continues to increase, the extrusion pressure tends to increase. In addition, the relationship between extrusion pressure component and die angle. Under a certain deformation condition, with the increase of die angle a, the required extrusion pressure component RM increases in the deformation area, which is due to the increase of additional bending deformation when metal flows out of the die hole. However, the component TM, which is used to overcome the friction resistance on the conical surface of the mould, decreases due to the decrease of the friction area. The combined effect of the above two factors makes RM+ TM the smallest under a certain mold angle, and the total extrusion pressure is also the minimum.

Influence of extrusion temperature on extrusion pressure

The influence of extrusion temperature on extrusion pressure is reflected by the magnitude of deformation resistance. The influence of deformation resistance on extrusion pressure of several copper alloys at different temperatures.

Generally speaking, with the increase of deformation temperature, the deformation resistance of ingot decreases, and the required extrusion pressure also decreases. In fact, the deformation resistance of most metals and alloys decreases with the increase of temperature, which can not maintain the strict linear relationship, so the relationship between extrusion pressure and temperature is generally nonlinear.