FR2965496A1 - "MULTI-EFFECT" FORM TOOLING FOR HIGH TEMPERATURE FORMING. - Google Patents

Abstract

The present invention relates to a tool of "multi-effect" shape (100) suitable for forming at high temperature metal parts (10), said tooling (100) comprising a fixed part (110) and a movable part (120) set action by a unidirectional press, in a first direction (Z), said tool (100) varying between an open position and a closed position in which the movable portion (120) exerts pressure on said fixed portion (110); said tooling (100) being characterized in that said movable part (120) comprises movable means (121, 122) capable of initiating a deformation of said metal part (10) by translation of said means (121, 122) in a second direction Y simultaneously with the translation of said means (121, 122) in said first direction (Z) during said closure of said tool (100).

Description

"MULTI-EFFECT" FORM TOOLING FOR HIGH TEMPERATURE FORMING.

The present invention relates to a tooling of "multi-effects" shape suitable for forming at high temperature metal parts such as for example a composite blade metal reinforcement, or metal, turbomachine. The tooling of "multi-effects" shape, according to the invention, is particularly well suited to the forming of a piece of complex geometry such as a metal reinforcement of turbomachine blade leading edge. The field of the invention is in particular that of turbomachines and more particularly that of the fan blades, made of composite or metallic material, of a turbomachine and whose leading edge comprises a metallic structural reinforcement. However, the invention is equally applicable to the production of all pieces of complex geometrical shape and to the production of metal reinforcements intended to reinforce a leading edge or a blade trailing edge of any type of turbomachine, whether terrestrial or aeronautics, and in particular a helicopter turbine engine or an airplane turbojet engine. It is recalled that the leading edge corresponds to the front part of an airfoil which faces the airflow and which divides the airflow into an intrados airflow and a flow of air. extrados air. The trailing edge corresponds to the posterior part of an aerodynamic profile where the intrados and extrados flows meet. The turbomachine blades, and in particular the fan blades, undergo significant mechanical stress, particularly related to the speed of rotation, and must meet strict conditions of weight and bulk. One of the options considered for lightening blades is the use of composite materials for their manufacture. It is known to equip the fan blades of a turbomachine, made of composite materials, with a metallic structural reinforcement extending over the entire height of the blade and beyond their leading edge as mentioned in EP1908919 filed by SNECMA. Such a reinforcement makes it possible to protect the composite trowel during an impact of a foreign body on the blower, such as for example a bird, hail or pebbles. In particular, the metal structural reinforcement protects the leading edge of the composite blade by avoiding risks of delamination, fiber breakage or damage by fiber / matrix decohesion. In a conventional manner, a turbomachine blade has an aerodynamic surface extending, in a first direction, between a leading edge and a trailing edge and, in a second direction substantially perpendicular to the first direction, between a foot and a dawn summit. The metallic structural reinforcement follows the shape of the leading edge of the aerodynamic surface of the blade and extends in the first direction beyond the leading edge of the aerodynamic surface of the blade to match the profile of the blade. the intrados and the upper surface of the dawn and in the second direction between the foot and the top of the dawn. In known manner, the metal structural reinforcement is a titanium metal part made entirely by milling from a block of material. However, the metal reinforcement of a blade leading edge is a complex piece to achieve, requiring many rework operations and complex tools involving significant realization costs. In this context, the invention aims to solve the problems mentioned above, by proposing a "multi-effects" shaped tool capable of forming high temperature metal parts, such as a leading edge metal reinforcement. turbomachine blade edge leak edge to simplify the manufacturing range and significantly reduce the costs of producing such a piece by proposing a "multi-effects" tooling implemented by a single-effect press. To this end, the invention proposes a tool of "multi-effects" shape suitable for high temperature forming of metal parts, said tool comprising a fixed part and a moving part actuated by a unidirectional press, in a first direction, said tooling varying between an open position and a closed position in which the movable portion exerts pressure on said fixed portion; said tool being characterized in that said movable part comprises movable means capable of initiating a deformation of said metal part by translation of said means in a second direction Y simultaneously with the translation of said means in said first direction during said closing said tools. By unidirectional press is meant a single-effect press having only one working axis, generally the vertical axis relative to the pressing plane of the press, as opposed to double or triple-effect presses respectively comprising two or three axes. oriented in different directions. By "multi-effect" is meant a deformation according to several directions occurring at several points of the part simultaneously in opposition to a simple deformation effect resulting from a single constraint applied locally in a single direction. Thanks to the invention, it is possible to perform a multi-effect deformation (Le in different directions simultaneously) by means of a low-cost single-effect press under conditions of high temperatures, that is to say temperatures required for the forging of the parts to be made. In the advantageous case of producing a turbomachine blade metal reinforcement, the piece is deformed and twisted in several directions in a single operation with a single-effect press and at a temperature greater than 850 ° C. 940 ° C for making a titanium reinforcement). Thus, the tooling according to the invention makes it possible to overcome the complex embodiment of the reinforcement by a method of milling in the mass from flats requiring large volumes of material and therefore the tool allows to reduce the quantities of raw materials necessary for the realization of such a metal reinforcement. The metal reinforcement of complex shape is made simply and quickly from a preform obtained from a simple metal bar and a succession of forging steps as described in particular in the patent application SNECMA FR1055066. The preform is then shaped three-dimensionally at high temperature in the "multi-effects" tooling by means of a single-effect press. Thus, the tool according to the invention makes it possible to perform a multi-effects deformation (Le in different directions simultaneously) by means of a simple and inexpensive press and under high temperature conditions, ie say above 850 ° C. The "multi-effect" shaped tooling according to the invention may also have one or more of the following characteristics, considered individually or in any technically possible combination: said tooling is an isothermal tool capable of forming at a higher temperature at 850 ° C; said fixed part comprises a matrix having two inclined walls able to move said moving means along said second direction Y during said closing of said tooling; each of said movable means comprises an inclined face parallel to one of said inclined walls of said matrix of the fixed part; said moving means are able to move away from said metal part by inverse translation of said moving means, in said second direction Y, simultaneously with the translation of said moving means along said first direction Z during said opening of said tooling; said movable part comprises at least one spacer integral with the movements of said movable part able to move said movable means from said part along said second direction Y during said opening of said tooling; said fixed part comprises means capable of forming a reference frame for positioning said metal part in the tooling; said tooling is suitable for forming a leading edge metal reinforcement or a turbomachine blade trailing edge; each of said moving means comprises a cavity representative of one of the external faces of said leading edge reinforcement or of the turbomachine trailing edge to be produced. The subject of the invention is also a forging method using said "multi-effects" shaped tooling according to the invention, characterized in that said method comprises the steps of: a step of placing said metal part preformed in said tooling; a step of closing said hole according to said first vertical direction Z, said closing step generating a translation of said moving means along said second direction Y initiating a deformation of said metal piece; - A step of maintaining the tool under pressure in its closed position at high temperature so as to form said metal part in its final form. Other characteristics and advantages of the invention will emerge more clearly from the description which is given below, by way of indication and in no way limiting, with reference to the appended figures, in which: FIG. 1 is a perspective view of the shaped tool according to the invention shown in its open position; - Figure 2 is a side view of the tool according to the invention during a closing phase; - Figure 3 is a side view of the form tool according to the invention in its closed position; - Figure 4 is a side view of the form tool according to the invention, illustrating the tooling during an opening phase; - Figure 5 is a side view of the tool according to the invention, illustrating the tooling shape in its open position.

In all the figures, the common elements bear the same reference numbers unless otherwise specified. Figure 1 is a perspective view of the form tool 100 according to the invention shown in its open position. Form tooling 100 is conventionally formed by a lower part 110, representing the fixed part of the tooling 100, and an upper part 120, representing the movable part of the tooling 100. The shaped screen 100 represented , As an example, in all the figures, is a tool allowing the realization of a titanium reinforcement of turbomachine blade leading edge.

The tooling is intended to be mounted on a single-acting press (not shown), of the forging press type, comprising a single working axis, generally the vertical axis, illustrated in FIG. 1 by the Z axis. Other embodiments, the tool can also be mounted on any type of forging machine pressure comprising a single working axis. In general, a forging is made by placing a preform or blank between two dies, an upper die and a lower die, each having a suitable fingerprint, and then bringing the two dies closer together with each other. a pressure sufficient to deform the preform to obtain a part whose geometry corresponds to that of the impressions, the forging operation being performed with the tool mounted temperature, that is to say at a temperature above 850 ° C for producing a titanium piece and preferably a temperature of the order of 940 ° C (plus or minus 10%). The lower part 110 of the tooling comprises in particular: - a lower support 111 adapted to be secured to the single-acting press (not shown); a lower die 112 having an impression 113 suitable for manufacturing a leading edge reinforcement; - Two support plates 116 bordering on either side the lower die 112 and each of which has in its upper part a notch 117 adapted to form a reference for the positioning of the preform 10 before closing the tool. In Figure 2, illustrating a side view of the shaped tool according to the invention shown in its open position, some elements, such as the support plates 116, are not shown to allow a better visualization of the arrangement. of the lower matrix 112.

The lower die 112 is formed by: a first lower portion 112b secured to the support 111, for example by screw connection comprising at least two longitudinal grooves 119, at its upper face distributed on either side of the center line; longitudinal of the lower portion 112a, illustrated by the X axis; - A second upper portion 112a having at its lower face positioning tabs 118 for positioning the upper portion 112a in the grooves 119 of the lower portion 112b; each lug 118 having the shape complementary to the shape of the longitudinal grooves 119 of the first lower portion 112a. The second upper portion 112a is secured to the first portion by securing means 132 forming pins and passing through both the first lower portion 112a at the longitudinal grooves 119 and the positioning tabs 118 of the upper portion 112b. The lower die 112 has a punch 114 whose upper portion forms a recess 113 conforming to the internal geometry of the leading edge of the turbomachine blade.

The lower portion 112b of the die 112 has a flare, substantially isosceles trapezium-shaped, adapted to receive the base of the punch 114, also of trapezoidal shape, and adapted to center the punch 114 in the die 112. The base of the punch 114 is trapped between the lower part 112a and the upper part 112b of the matrix 112, and more precisely in a space 115 bordered on the one hand by the flaring of the lower part 112a and on the other by two horizontal tabs 133 protruding inward of the tool 110 in the upper part. Thus, these two horizontal tabs 133 of the upper portion 112b perform a stop function allowing only a certain vertical displacement (ie along the Z axis shown in Figure 1) of the base of the punch 114 in the space 115 defined. The game thus created advantageously authorizes a calibrated movement between these different parts of the die 112, making it possible to produce a punch 114 floating in the space 115 capable of facilitating the demolding of the part made in the tooling 100. The other movements, transverse and longitudinal, the punch 114 are respectively blocked by the flared shape of the lower portion 112a receiving the base of the punch 114 and the support plates 116 bordering on either side the punch 114. The support plates 116 are secured on the lower part 112a of the die 112 by conventional securing means used in this type of press tooling by forging.

The upper part 120 of the tooling comprises in particular: - an upper support 123 adapted to be secured to the single-effect press (not shown); two upper matrices 121 and 122, each of which has an imprint, respectively referenced 124 and 125, corresponding to the external geometry of one of the faces of the turbomachine blade leading edge reinforcement to be produced. The two upper matrices 121 and 122 have the particularity of generating a complex motion different from the displacement imposed by the single effect press.

FIG. 2 illustrates more precisely the respective movements of the two matrices 121, 122, by the arrows referenced 150, during the closure of the press, whose opening / closing displacement is symbolized by the vertical arrows 160. Indeed, the two upper matrices 121, 122 perform a translation along the Y axis during the displacement of the upper support 123 along the Z axis. The translation of the upper matrices 121, 122 during the closure of the press is enabled by the complementary shape of the upper matrices 121, 122 and the lower die 112. The face 131 of the lower die 112 facing towards the inside of the tool 100 forms a slope on which the upper dies 121, 122 slide during the closure of the press , by generating a transverse displacement complementary to the vertical displacement along the Z axis. The transverse movement of the upper dies 121, 122 is relatively guided by a guide 134 , for example a free cylindrical axis, allowing the two upper dies 121, 122 to be guided during the closing and during the opening of the press. Therefore, the two upper dies 121, 122 initiate deformation and possibly twisting of the preform 10, introduced into the tool, during the closing of the tool and from the beginning of the closing phase of the tooling 100. The upper dies 121 and 122 comprise in the upper part a bearing surface 135, on which the support 123 transmits the thrust of the press. This bearing surface is oriented substantially perpendicular to the direction of the thrust of the upper dies 121, 122, illustrated by the arrows 150. The orientation of this bearing surface 135 limits the torque generated on the upper dies. 121, 122 and thus avoid twisting the upper dies 121, 122 when closing the press.

FIG. 3 illustrates the form tooling 100 previously described in the closed position. During the ascent of the upper part 120 of the tooling 100, in the opening phase, as illustrated in FIGS. 4 and 5, two spacers 141 (only one being shown) integral with the upper support 123 make it possible, through their form, to separate the two upper dies 121, 122 of the forged part. The spacers 141 have a bevelled outer surface 136 forming a slope and providing a bearing surface capable of sliding on the upper dies 121, 122 during the opening of the tool 100. Thus, during the ascent of the tooling 120, the spacers 141 rise vertically, according to the arrow referenced 161, illustrated in Figure 4, come into contact with the upper dies 121, 122 and then push the upper dies 121, 122 in a transverse direction, perpendicular to the direction of the opening of the tooling 100. When the spacers 141 are in contact with the two upper dies 121, 122, they have a surface 137 resting on the outer surface 136 of the spacers 141, so that the retraction of the spacers 141 spreads, under the effect of gravity, the upper dies 121, 122 by sliding on both the surface 136 of the spacer 141 and on the bearing face 131 of the die lower part 112 in the direction illustrated by the arrow referenced 151. FIGS. 4 and 5 respectively illustrate the tooling in the low position during the upstroke phase of the press and the tooling in the up position during the press up phase. .

In the up position, as illustrated in FIG. 5, the upper dies are positioned resting on the spacers 141 by means of horizontal stops 138 and slopes 137. Thus, the device is operative for shaping the next piece . Thanks to the invention, the automatic spacing (in opposition with a manual spacing of an operator) makes it possible to quickly prepare the tooling for forming a subsequent part without the intervention of an operator and without cooling the tooling . In order to facilitate demolding of the part produced, especially cold, the cavity 113 may be constituted by a plurality of movable or removable sections and able to disassemble individually. In order to facilitate demolding, it is also possible to initially prepare the tooling 100 by depositing a protective layer on the cavities 113, 124, 125 so as to prevent the forged part from sticking to the tooling 100. For example, this protective layer may be an aluminum oxide layer. The invention has been particularly described for the production of a metal reinforcement of a turbomachine composite blade; however, the invention is also applicable for producing a metal reinforcement of a turbomachine metal blade. The invention has been particularly described for producing a metal reinforcement of a turbomachine blade leading edge; however, the invention is also applicable for producing a metal reinforcement of a trailing edge of a turbomachine blade.

The other advantages of the invention are in particular the following: reduction of implementation costs; - reduction of the production time; - simplification of the manufacturing range; - reduction of tooling costs; - reduction of material costs.

Claims (10)

REVENDICATIONS1. "Multi-effect" shaped tooling (100) capable of forming metal parts at high temperature (10), said tooling (100) comprising a fixed part (110) and a moving part (120) actuated by a unidirectional press in a first direction (Z), said tool (100) varying between an open position and a closed position in which the movable portion (120) exerts pressure on said fixed portion (110); said tooling (100) being characterized in that said movable part (120) comprises movable means (121, 122) capable of initiating a deformation of said metal part (10) by translation of said means (121, 122) in a second direction (Y) simultaneously with the translation of said means (121, 122) in said first direction (Z) during said closing of said tool (100). 2. Tooling of "multi-effect" shape (100) suitable for forming high temperature metal parts (10) according to claim 1 characterized in that said tooling is an isothermal tool capable of forming at a temperature greater than 850 ° C . 3. Tooling "multi-effects" form (100) suitable for forming high temperature metal parts (10) according to one of claims 1 to 2 characterized in that said fixed portion (110) comprises a matrix (112) having two inclined walls (131) able to move said movable means (121, 122) in said second direction Y during said closure of said tool (100). 4. Tooling of "multi-effect" shape (100) capable of forming high temperature metal parts (10) according to claim 3 characterized in that each of said movable means (121, 122) has an inclined face parallel to the one of said inclined walls of said die (112) of the fixed portion (110). 5. Tooling of "multi-effect" shape (100) capable of forming high temperature metal parts (10) according to one of claims 1 to 4 characterized in that said movable means (121, 122) are suitable for s moving away from said metal piece (10) by inverse translation of said moving means, in said second direction Y, simultaneously with the translation of said moving means (121, 122), in said first direction (Z), during said opening of said tooling (100). 6. Tooling "multi-effects" form (100) suitable for forming high temperature metal parts (10) according to claim 5 characterized in that said movable portion (120) comprises at least one spacer integral with the movements of said part mobile (120) adapted to move said movable means (121, 122) of said piece (10) in said second direction (Y) during said opening of said tool (100). 7. Tooling "multi-effects" form (100) suitable for forming high temperature metal parts (10) according to one of claims 1 to 6 characterized in that said fixed portion (110) comprises means (116) adapted to form a reference system for positioning said metal part (10) in the tooling. 8. Tooling "multi-effects" form (100) capable of forming high temperature metal parts (10) according to one of claims 1 to 7 characterized in that said tool (100) is capable of forming a turbomachine blade leading edge or trailing edge reinforcement. 9. Tooling "multi-effects" form (100) suitable for forming high temperature metal parts (10) according to claim 8 characterized in that each of said movable means (121, 122) comprises an imprint (124, 125) representative of one of the outer faces of said leading edge reinforcement or turbomachine trailing edge to be produced. 10. forging process using said tooling of "multi-effects" form (100) according to one of claims 1 to 9 characterized in that said method comprises the steps of: - a step of setting up of said preformed metal part in said tooling (100); - A step of closing said screen (100) in said first vertical direction Z, said closing step causing a translation of said moving means (121, 122) in said second direction Y initiating a deformation of said metal piece (10); a step of holding the tool (100) under pressure in its closed position at high temperature so as to form said metal part in its final form.