The metallic extrusion molding method of rotating cavity die
Technical field
The present invention relates to a kind of section bar extrusion forming method.
Background technology
Extrusion molding is the metal ingot blank in the Extruding die is applied external force and to obtain a kind of plastic processing method of required section configuration and size.It is a lot of to influence in the extrusion process factor of metal flow, and as friction and lubricating condition, mould structure and blank temperature etc., wherein friction is one of critical boundaries condition of decision extruded product performance.With the forward extrusion is example, and the inhibition that rubbed very easily causes to produce mobile defect in the forming process, and has consumed a large amount of extruding energy; And it is surplus to leave certain pressure during the extruding of quiet liquid, and poor controllability, the production efficiency of extrusion speed are lower, and actively the required device of friction and Extrusion is more loaded down with trivial details, and in production practices, use less relatively.It is single optimization by technological parameter that tradition is improved the way of metal flow in the extrusion process, thereby changes the flow behavior of metal on a macro scale, but this can not fundamentally prevent generation of defects; And frictional force has consumed bigger extruding energy between blank and mould, and for the shaping of inductile metal material, production efficiency is extremely low, more is difficult to carry out the production and processing of heavy in section size section bar especially.
Based on the above, publication number is US7096705B, open day be the metallic extrusion molding method that the application for a patent for invention on August 29th, 2006 has proposed a kind of rotating cavity die, though the manufacturing process described in the literary composition has reduced the shaping load in the extrusion process, brought the low drawback of formed product qualification rate.
Summary of the invention
The metallic extrusion molding method that the purpose of this invention is to provide a kind of rotating cavity die, with solve exist in the present metallic extrusion molding process plasticity significantly flow inhomogeneous, easily produce mobile defect, problem that the formed product qualification rate is low.The present invention is finished by following steps: one, core is fixed on the workbench; Two, rolling bearing is placed on the shoulder end face of core and be installed in the outside of core; Three, place die on the rolling bearing and be enclosed within on the core; Four, the blank for preparing is put into the die cavity of die; Five, die rotates by a fixed angular speed, and blank and die rotate in the same way; Six, drift moves down and exerts pressure, and blank is extruded in the die cavity of die vertically.
The present invention has following beneficial effect: die rotates the action direction that can change frictional force between blank and the die by a fixed angular speed, shaping load in the extrusion process is significantly reduced, and can reduce the generation of mobile defect, because the extruded product streamline is certain helical form around distribution, therefore the tendency that can avoid being shaped the stress corrosion of section bar end, back and produce cracking, ground best in quality lightweight inductile section bar can disposablely be shaped, compare with traditional processing technology, the section bar that this method is produced has light weight, the intensity height, performance is good, advantages such as the equipment needed thereby tonnage is little, the present invention is reasonable in design, reliable operation, effect is remarkable, has stronger promotional value.
Description of drawings
Fig. 1 is the structure half sectional view of the mould of the specific embodiment one, and Fig. 2 is the structure half sectional view of the mould of the specific embodiment two.
The specific embodiment
The specific embodiment one: in conjunction with Fig. 1 present embodiment is described, present embodiment is finished by following steps: one, core 2 is fixed on the workbench 1; Two, rolling bearing 3 is placed the shoulder end face 2-1 of core 2 go up and be installed in the outside of core 2; Three, place die 4 on the rolling bearing 3 and be enclosed within on the core 2; Four, the blank 5 for preparing is put into the die cavity 4-1 of die 4; Five, die 4 rotates by a fixed angular speed, and blank 5 rotates in the same way with die 4; Six, drift 6 moves down and exerts pressure, and blank 5 is extruded in the die cavity 4-1 of die 4 vertically.Rotate by die, the action direction of frictional force between blank and die is changed, it is required during extrusion molding that what overcome only is effective skin friction one-component in the axial direction, therefore, shaping load in the extrusion process is significantly reduced, and can make that the uniformity of metal flow is improved in the extrusion process, be particularly suitable for the usefulness of the shaping of lightweight inductile metal structure section bar.Change along with the die rotating speed, the numerical value of effective skin friction component also will change, can make the shaping load in the extrusion process continue to reduce, and, blank rotates owing to being subjected to the effect of die frictional force, therefore, the streamline of extrusion profile is non-parallel distribution, and section bar end, the back stress of can avoiding being shaped is corroded and the tendency of generation cracking.
The specific embodiment two: in conjunction with Fig. 2 present embodiment is described, die 4 is by deciding die 7 and moving die 8 is formed in the present embodiment; Decide die 7 and place moving die 8 tops.Die can be divided into decide die and moving die two parts, the rotation that only moving die is applied certain orientation to the blank extrusion molding time can reach the requirement that reduces load, and required die rotational load is less.
The specific embodiment three: present embodiment is in step 4, and blank 5 is magnesium alloy, aluminium and alloy thereof, titanium and alloy thereof.