Copper alloy extrusion temperature
Determining the extrusion temperature of copper alloys
Copper and copper alloys should have low deformation resistance and good plasticity at the extrusion temperature. The reasonable extrusion temperature range should be determined based on the plasticity diagram, recrystallization diagram, and phase diagram of the alloy, and considering the actual production conditions.
(1) The heating temperature is generally 0.75~0.95 times the melting point temperature of the alloy. The upper limit of the extrusion temperature range can be determined based on the melting points of the metal and alloy and the solid phase point temperature of the alloy on the phase diagram to avoid heat during extrusion. Brittleness (overheating, overburning phenomenon). The lower limit of the extrusion temperature range should consider good plasticity at high temperatures and should also ensure that the deformation resistance of metals and alloys is not too high.
(2) For alloys that undergo phase change at high temperatures, it is best to perform hot extrusion in the single-phase region.
(3) Hot extrusion should be carried out at a temperature within the high-temperature plastic zone as much as possible to avoid transverse cracks. But at the same time, the surface properties of the alloy at high temperatures should be considered to prevent excessive oxidation or bonding of the ingot surface. The viscosity of certain alloys to tools increases with temperature, such as white copper, aluminum bronze, etc. Consider using lower temperature extrusion as much as possible. Additionally, extruder capacity also needs to be considered when considering extrusion temperature. When using lower extrusion temperatures, large ton extruders should be used.
(4) The extrusion elbow deforms greatly and the deformation speed is fast. The friction between the metal and the tool will generate a lot of heat, which can cause the temperature of the ingot to rise during the extrusion process. When determining the heating temperature, try to use the temperature
Lower limit squeeze.
(5) Different mechanical properties can be obtained by extruding at different temperatures. When selecting the extrusion temperature, the performance requirements of the product should be considered. When some alloys are extruded at higher temperatures, the tail shrinks too long and the pressure residue increases, such as HPb59-1, etc. When extruding brass, the temperature is too low, and strips are easily formed at the end of the extruded product.
The shape, deformation degree, tool temperature, lubrication conditions, etc. of extruded products all have a certain impact on the extrusion temperature.
