Process for shaping a semi-finished product intended for use as an electrical contact element, semi-finished product intended for use as an electrical contact element

Abstract

The present invention relates to a method for shaping a semi-finished product (100) intended for use as an electrical contact element. In a coating step, a coating having Ag as a component, particularly in matrix form, is applied to an electrically conductive base body of the semi-finished product (100) in a coating direction, and the coating is shaped, in a subsequent shaping step, by forming, particularly by drawing, the semi-finished product (100) through an orifice or by profile rolling. The invention further relates to a semi-finished product (100) intended for use as an electrical contact element, said semi-finished product (100) comprising an electrically conductive base body and a coating on the base body having Ag as a component, particularly in matrix form, being modified by forming, particularly by drawing or profile rolling. Figure for the abstract: Figure 4C

Description

Title of the invention: Method for shaping a semi-finished product intended for an electrical contact element, semi-finished product intended for an electrical contact element

[0001] The present invention relates to a method of shaping a semi-finished product intended for an electrical contact element.

[0002] The semi-finished product may, for example, be of elongated shape and may serve to form a cage-like housing for a counterpart contact element. It is known to apply, in a coating step on an electrically conductive base body of the semi-finished product, a coating having Ag (silver) as a component in one coating direction. As a result, for example, a contact resistance may be improved.

[0003] The layers thus applied often do not have the desired hardness in combination with low contact resistance, or the desired low coefficient of friction.

[0004] The aim of the present invention is therefore to provide a solution with which the semi-finished product has the desired advantageous properties.

[0005] The object of the present invention is achieved by shaping the coating, during a processing or shaping step following the coating step, by means of a forming step, such as stretching the semi-finished product through an orifice or rolling a profile. The forming step makes it possible to obtain the desired properties.

[0006] Thus, the invention relates to a method for shaping a semi-finished product (for an electrical contact element), in which, in a coating step, a coating having Ag as a component, in particular in matrix form, is applied to an electrically conductive base body of the semi-finished product in a coating direction, in which, in a shaping step following the coating step, the coating is shaped by forming, in particular by stretching, the semi-finished product through an orifice or by profile rolling.

[0007] In the case of a semi-finished product according to the present invention, the coating has Ag as a component, for example in the form of a matrix coating, and is modified by the forming step, in particular by profile drawing or rolling. The semi-finished product and / or the coating may, for example, correspond to the cross-section of the orifice and / or have (micro)grooves or (micro)patterns produced by profile drawing or rolling.

[0008] The invention thus also relates to a semi-finished product intended for an electrical contact element, comprising an electrically conductive base body and a coating on the base body, in which the coating has Ag as a component, in particular in matrix form, and is modified by forming, in particular by profile drawing or rolling.

[0009] The solution according to the present invention can be further improved by means of the following developments and embodiments, which can be combined with each other in any advantageous manner.

[0010] In the forming step, a force perpendicular to the surface may be exerted on the coating. This may result in a modification of the coating.

[0011] The coating may surround the base body along a circumferential direction. With such a semi-finished product, it is no longer necessary to ensure correct alignment during subsequent processing into a contact element. The coating may have a constant thickness along the circumferential direction, at least before the processing step comprising forming. In other embodiments, the layer thickness may vary along the circumferential direction, depending on which properties are desired there and to what extent they are desired there.

[0012] In alternative embodiments, the coating may also be present only on parts of the circumference. Thus, for example in the case of a rectangular cross-section, a coating may only be present on one side. Such a side may for example be a side on which a contact surface is located, or a side serving for mechanical guidance of the contact element.

[0013] The semi-finished product may be a wire, in particular a round wire or a profiled wire. Said wire may be used in many ways to produce a contact element. The drawing may in this case be wire drawing.

[0014] The basic body itself can be produced by drawing or by profile rolling before the coating step. The basic body can also be considered a semi-finished product, since it is subjected to further processing steps.

[0015] In alternative embodiments, the semi-finished product may be an elongated element. In particular, there may be a cross-section that remains constant in a longitudinal direction. The cross-section may be elliptical, rectangular or polygonal or have any other shape.

[0016] In order to further influence the properties in the desired manner, the coating may have at least one additional component. Component here refers in particular to a material component, i.e. the material of the coating consists of or has such material components.

[0017] In an advantageous embodiment of the method, Ag and the additional component may be applied as separate layers or within separate layers. The process can thus be implemented particularly simply.

[0018] The coating and layers can be applied by usual methods, for example by hot dipping, electroplating, by mechanical methods such as plating or by PVD (physical vapor deposition) or CVD (chemical vapor deposition).

[0019] In order to enhance the forming effect, Ag and the additional component may be applied in alternating layers or within alternating layers. Different materials are respectively present in two successive layers. The alternating layers comprise at least one layer of Ag, one layer of the additional component and a second layer of Ag. Both layers of Ag may contain the layer comprising the additional component. Preferably, four or more layers are present. These may in particular be repeated according to a defined pattern, for example ABABAB-... or ABCABC-

[0020] In another advantageous embodiment, at least two successive layers may be made of the same material. Thus, in terms of process technique it may for example be simpler to apply two thinner layers of one material, then another thin layer of another material, i.e. for example AABAAB.

[0021] In an advantageous embodiment, the layer thickness for the Ag is between 100 and 2000 nm, preferably between 200 and 1000 nm, particularly preferably between 300 and 600 nm. The layer thickness of the additional component may be between 5 and 200 nm, preferably between 10 and 100 nm, particularly preferably between 30 and 60 nm. With such layer thicknesses, the forming effect can be particularly effective.

[0022] The alloy content of the additional component in the coating may be 0.3-15%, preferably 0.5-10%. This may provide a coating having properties, in particular mechanical properties, which are particularly advantageous. The percentages are given here in atomic %, i.e. the percentage of atoms of the additional component relative to the total number of atoms in the coating.

[0023] By means of forming, the Ag and the additional component can be alloyed. In particular, the components can be mechanically alloyed. This is possible by mixing under high pressure during forming, for example when drawing through the drawing orifice / die. To achieve a particularly good result here, a plurality of thin layers can be used. In particular, at least 8, preferably at least 16 layers can be present.

[0024] In an advantageous embodiment, a material is used as an additional component which hardens the Ag matrix during alloying. An alloy consisting of Ag and additional components can be harder than Ag. The hardness thus obtained makes it possible to reduce abrasion and thus extend the service life of a contact element produced in said alloy.

[0025] The additional component contains, for example, at least one material from the group Ni (nickel), Pd (palladium), Ru (ruthenium), Ti (titanium), Mo (molybdenum), W (tungsten), Au (gold), Cu (copper), or is made of such a material.

[0026] In another advantageous embodiment, the additional component can function as a barrier layer which slows down or prevents diffusion phenomena within the layer and thus improves the corrosion resistance and thermal stability of the layer. In addition, the additional component can slow down or prevent crystal growth of the matrix and thus stabilize the fine crystal structure produced by forming, in particular by wire drawing. A layer thus produced retains its hardness, abrasion resistance and corrosion resistance even when used at high temperatures (150°C to 250°C). This is particularly the case when nickel (Ni) is used as the additional component.

[0027] In another advantageous embodiment, the additional component may be incorporated in the form of particles in an Ag layer. Such particles may, for example, be present in the electroplating bath during an electroplating application and be deposited during the coating process. Suitable particles may also be present in the dipping tank in the case of a coating process comprising dipping. In vacuum coating processes such as chemical vapor deposition or physical vapor deposition, the second component may be deposited by co-sputtering / evaporation or coating from an Ag matrix alloy target.

[0028] By means of forming, in particular by drawing or rolling of profiles, the particles can be given a preferred orientation, i.e. a preferred orientation can be provided to the particles, or a preferred orientation of the particles can be changed. The particles can, for example, be in the form of flakes, ribbons or threads, and a preferred orientation can be defined with respect to an orientation of a plane or a longitudinal direction of said particles. In particular, a longitudinal direction of the particles can be parallel to a longitudinal direction of the base body. In particular, particles which are on the surface of the semi-finished product can thus provide a particularly significant effect. In a semi-finished product processed or shaped in said manner, the particles of the additional component have a preferred orientation. The shape of the particles can also be changed by drawing.

[0029] The particles may have a spherical or ellipsoidal shape of revolution before treatment. Said shape may be modified by stretching. The shape may in particular be flattened. The flat sides of such a shape may rest on the surface or be oriented towards the surface.

[0030] The particles may have friction-reducing properties. In particular, the insertion or guiding of the contact element may thus be facilitated and / or wear may be reduced.

[0031] The additional component may contain at least one material from the group graphene, graphite, carbon nanotubes, sulfides, sulfur sulfide, molybdenum sulfide, tungsten sulfide, hexagonal boron nitride, PTFE (polytetrafluoroethylene), or be made of such a material.

[0032] Forming, in particular stretching or rolling of a profile, makes it possible to produce a preferred orientation of the crystallites within or at the surface of the coating or to modify the preferred orientation of the crystals at the surface or in the coating. This can be done regardless of whether the coating contains a single layer or a plurality of layers and regardless of whether particles are present in one or more layers.

[0033] At a surface of a semi-finished product, in particular a semi-finished product thus processed or shaped, crystallites may terminate mainly in one or two crystal plane(s). This may be, for example, a crystal plane <111> and / or a plan <110> , particularly in the case of an Ag-type network. A proportion may be considered predominant if a termination is present along such a crystal plane over more than 30%, preferably more than 50%, of the surface.

[0034] In a particularly advantageous embodiment, the coating may comprise at least two other components in addition to Ag. The properties can thus be influenced in a particularly positive manner.

[0035] In a further process step, the coated semi-finished product treated by shaping, in particular by drawing or profile rolling, can be heat treated. For this purpose, the semi-finished product can be brought to a defined temperature for a certain time, for example by current flow, in a dipping tank or in a furnace. Rapid cooling / quenching, for example by dipping, can also be part of the heat treatment. In particular, the hardness of the coating and / or the semi-finished product can be changed.

[0036] The material for the base body may comprise in particular copper, a copper alloy, aluminum, an aluminum alloy, iron or steel, in order to allow a particularly mechanically stable structure.

[0037] Another layer may be present between the base body and the coating. Said layer may be used, for example, to enable the adhesion of components applied or to produce or increase conductivity. The additional layer may include Cu (copper) or be made of Cu; to act as an adhesion base, layers of Ni or NiP or a primer made of an alloyed metal may also be applied.

[0038] The present invention also relates to an electrical contact element comprising at least one semi-finished product according to the present invention. The contact element may, for example, have a barrel- or funnel-shaped housing made of the semi-finished product and into which a corresponding pin-shaped contact element can be inserted.

[0039] The present invention is explained in more detail below with the aid of examples and advantageous embodiments with reference to the figures. The developments and advantageous embodiments shown are respectively independent of each other and can be combined with each other in any manner as required.

[0040] We can see that:

[0041] [Fig.1A] is a schematic sectional view of one embodiment of a coating step;

[0042] [Fig. 1B] is a schematic sectional view of one embodiment of a coating step;

[0043] [Fig. 1C] is a schematic sectional view of one embodiment of a coating step;

[0044] [Fig.2A] is a schematic sectional view of one embodiment of a processing step;

[0045] [Fig.2B] is a schematic sectional view of one embodiment of a processing step;

[0046] [Fig.2C] is a schematic sectional view of one embodiment of a processing step;

[0047] [Fig.3A] is a schematic sectional view of another embodiment of a coating step;

[0048] [Fig.3B] is a schematic sectional view of another embodiment of a coating step;

[0049] [Fig.3C] is a schematic sectional view of another embodiment of a coating step;

[0050] [Fig.3D] is a schematic sectional view of another embodiment of a coating step;

[0051] [Fig.4A] is a schematic sectional view of another embodiment of a processing step;

[0052] [Fig.4B] is a schematic sectional view of another embodiment of a processing step;

[0053] [Fig.4C] is a schematic sectional view of another embodiment of a processing step;

[0054] [Fig.5] is a schematic sectional view of another embodiment of a semi-finished product;

[0055] [Fig.6] is a schematic sectional view of another embodiment of a processing step;

[0056] [Fig.7] is a schematic side view of another embodiment of a partially shaped semi-finished product;

[0057] [Fig.8] is a schematic sectional view of another embodiment of an unshaped semi-finished product;

[0058] [Fig.9] shows a detail of the sectional view of the unshaped semi-finished product of [Fig.8];

[0059] [Fig. 10] is a schematic sectional view of the embodiment of [Fig.9] after a processing step;

[0060] [Fig. 11] shows a detail of the sectional view of the shaped semi-finished product of [Fig. 10];

[0061] [Fig.12] shows another enlarged detail of the shaped semi-finished product of [Fig.10]

[0062] [Fig. 13] is a schematic perspective view of one embodiment of a contact element.

[0063] A coating step B is shown in Figures 1A, 1B and 1C. A coating 30 is applied to an electrically conductive base body 20 which can be considered as a semi-finished product 100. This can be achieved by conventional methods, for example by hot dipping, mechanical coating, electroplating, physical vapor deposition (PVD) or chemical vapor deposition (CVD).

[0064] The semi-finished product 100 may for example be a wire 101. Such a wire 101 may have an elongated configuration with a constant cross-section. The cross-section may be in particular circular or quasi-cylindrical cylindrical, but also polygonal, in particular rectangular or octagonal. The wire 101 may be produced by wire drawing or profile rolling.

[0065] In the case of a wire, the coating 30 can be applied in the circumferential direction U over the entire surface of the cylinder envelope.

[0066] In other embodiments, the base body 20 may also have a different shape. For example, the base body 20 may be a plate or a strip. A plate or strip may have a rectangular or polygonal. The coating 30 may also be present only on parts of the outer surface. In the case of a strip or a plate, it is possible to coat, for example, only one side, namely a side which is used for mechanical or electrical contact.

[0067] The coating 30 is applied in a coating direction S which corresponds for the wire 101 to a radial direction R. Layer thicknesses 81, 82, 83, 85 of the coating 30 or of individual layers 31, 32, 33 are also measured in the coating direction S or in a height direction H which runs parallel to the coating direction S. The individual layers 31, 32, 33 are applied one on top of the other in the coating direction S. The coating direction S is thus perpendicular to a longitudinal direction L of the base body 20.

[0068] A processing step Z in which the coated semi-finished product 100 is processed or shaped, for example by profile drawing or rolling, is shown in FIGS. 2A, 2B and 2C. In the case of drawing, the base body 20 is pulled through an orifice 91, see also [Fig. 6].

[0069] The orifice 91 may be part of a drawing die 90 having orifices 91 of different sizes in order to successively implement several drawing steps. The orifices 91 may respectively be designed in the shape of a funnel in order to allow easy drawing.

[0070] The height 80 of the base body 20 is reduced by drawing. In the case of the wire 101, the height 80 corresponds to the diameter 70.

[0071] As can be seen in [Fig.6], a first diameter 71 is present before the stretching step and a second diameter 72 smaller than the first diameter 71 is present after the stretching step. An elongation of the semi-finished product 100 in a longitudinal direction L may occur due to the stretching. [Fig.7] represents a microscopic view of a partially stretched semi-finished product 100.

[0072] When stretching through the orifice 91, mechanical pressure is exerted on the base body 20 and in particular on the coating 30. The properties of the coating 30 can in particular be positively influenced in this way.

[0073] Drawing or stretching is a particular forming method. Another forming method may be profile rolling. During this forming, a force is exerted respectively on the coating 30 against the coating direction S. The coating 30 is then formed and its properties are modified.

[0074] Figures 3A, 3B, 3C and 3D show an embodiment of a coating step B. Layers 39 of different materials are applied alternately to the base body 20. The material of a first layer 31 differs from the material of a second layer 32 applied to the first layer 31. A third layer 33 applied to the second layer 32 may consist of a other material, which differs from the material of the first layer 31 and the material of the second layer 32, or from the same material as the first layer 31. Said method can be repeated until a desired number of layers 39 is present. A repeated sequence of layers of different materials, for example an alternating sequence of layers ABABAB-..., or three repeated layers ABCABC-..., can be applied here. Of course, other sequences of layers can also be used, in particular non-repeated sequences of layers. Furthermore, it can for example be envisaged that two successive layers consist of the same material, i.e. for example AABAAB-... This may be easier to produce in terms of process technology.

[0075] Coating step B produces a coating 30 with a layer thickness 85 corresponding to the sum of the layer thicknesses of the individual layers 39, i.e., in the example shown, the sum of the layer thickness 81 of the first layer 31, the layer thickness 82 of the second layer 32 and the layer thickness 83 of the third layer 33. At least one of the layers 39 contains silver (Ag) or consists entirely of it.

[0076] The coating 30 may have other components, in particular at least one material from the group Ni (nickel), Pd (palladium), Ru (ruthenium), Ti (titanium), W (tungsten), Au (gold), Cu (copper), Fe (iron), Co (cobalt) or Mo (molybdenum). For example, a layer 39 comprises such a material or is made of such a material. These materials may in particular contribute to improving mechanical properties such as hardness, for example by hardening the Ag.

[0077] Figures 4A, 4B and 4C show how such a coating 30 is modified by forming, in particular by stretching. Due to the mechanical pressure, the individual layers 31, 32 and 33 are mechanically mixed together. After stretching, the shaped coating 38 can be considered as a single layer 39. The layer thickness 85 has thus decreased. As can be seen in Figures 2A to C, the diameter 79 of the base body 20 has also decreased.

[0078] Stretching or rolling the profile may result in mixing and / or alloying of the materials of the individual layers 31, 32, 33, 39. Such mechanical alloying modifies the properties of the coating 30. For example, the coating may then have a harderness greater than that of each of the components of the unshaped coating 30.

[0079] The shaped semi-finished product 100 may have traces of forming, in particular of profile drawing or rolling. For example, the cross-section of the semi-finished product 100 may correspond to the orifice 91. Furthermore, grooves or wave-shaped topographies, resulting for example from small projections in the orifice or which can be placed in a targeted manner, may be present along a longitudinal direction L.

[0080] [Fig. 5] shows another embodiment in which the coating 30 is not made up of different layers 39, but of particles 40 embedded in a single layer 39. The layer 39 may again comprise Ag, in particular in matrix form, i.e. in the form of a base material or a base structure. The particles 40 comprise other materials which may, for example, have friction-reducing properties. The particles 40 may contain a material from the group graphene, graphite, carbon nanotubes, sulfides, sulfur sulfide, molybdenum sulfide, PTFE (polytetrafluoroethylene), tungsten sulfide or hexagonal boron nitride or may be made of such a material.

[0081] The particles 40 may for example be placed in the coating 30 during the coating step B. If the coating 30 is created by dipping or electroplating, the particles 40 may be present in the liquid and deposited randomly. The concentration of the particles 40 in the coating may be controlled, for example by the concentration of the particles 40 in the liquid.

[0082] The particles may be asymmetrical or symmetrical, in the form of flakes, ribbons or threads. The orientations of the particles 40 may be advantageously modified by the processing step Z comprising forming, in particular drawing or rolling of the profile. For example, in the case of a wire-shaped embodiment, the longitudinal directions of the threads may be oriented parallel to the longitudinal direction L of the semi-finished product 100 along which a rolling or drawing movement takes place. A surface 50 of the semi-finished product 100 may in particular be thus formed to a large extent by means of the surfaces of the particles 40. The coefficient of friction may therefore be very low.

[0083] In the case of a flake or strip embodiment, the orientation of the particles 40 can be modified by stretching so that their surfaces rest on the surface 50 of the semi-finished product. It also follows that the properties of the semi-finished product 100 on the surface are decisively defined by the properties of the particles 40, for example the non-stick properties.

[0084] The particles 40 may be spherical prior to processing. By processing step Z comprising forming, the particles 40 may be flattened and / or stretched and one of their flat sides is oriented toward the surface 50 or rests on the surface 50.

[0085] Furthermore, the concentration of the particles 40 at the surface 50 can be increased by means of the processing step Z comprising forming. This also has a positive influence on the properties of the semi-finished product 100.

[0086] Figures 8 and 9 show microscopic views of a cross-section of a semi-finished product 100 in the form of a wire 101 after a coating step B, but before a processing step Z. In addition to the base body 20 made of steel and the coating 30, an intermediate layer 25 containing copper and which can serve to allow the conduction of a current and / or the adhesion of the coating 30 to the base body 20. The wire 101 has a diameter of approximately 0.5 millimeters at this stage. As can be seen in [Fig. 9], the coating 30 comprises several separate layers 39. Comparatively thick Ag layers 30, 33 alternate with thinner palladium (Pd) layers 32, 34.

[0087] The alloy content of the additional component of the coating, here for example palladium, may be between 0.3 and 15%, preferably between 0.5 and 10%. This can give a coating having particularly advantageous properties, in particular mechanical properties.

[0088] In Figures 10 to 12, the wire 101 is shown after a treatment step Z. It now has a diameter of approximately 0.3 millimeters. It can be seen in particular in [Fig. 12] that Ag and Pd are mechanically alloyed in regions where a high mechanical load is present in the coating 30, see regions 65.

[0089] Crystallites 60 may also be seen. The coating 30 may be modified by stretching so that the crystallites 60 terminate at the surface 50 primarily in one or two crystal planes, for example in a plane <111> Or <110> . This can also have a positive influence on the properties.

[0090] [Fig. 13] shows a contact element 200 that can be produced from a wire 101. Individual segments of the wire 101 are bent and connected to form a conical housing for a counterpart contact element. By means of the processing comprising a forming step, in particular a drawing step or a rolling step, friction properties such as a coefficient of friction or a hardness are in particular changed. The service life of such a contact element 200 can thus be extended.

[0091] Numerical references 20 basic bodies 25 intermediate layer 30 coating 31 first layer 32 second layer 33 third layer 34 fourth layer 38 shaped coating 39 layer 40 particles 50 surface 60 crystallite 65 region 70 diameter 71 first diameter 72 second diameter 79 base body diameter 80 height 81 layer thickness of the first layer 82 layer thickness of the second layer 83 layer thickness of the third layer 84 layer thickness of the fourth layer 85 layer thickness of the coating 90 drawing die 91 hole 100 semi-finished product 101 thread 200 contact element B coating step The longitudinal direction R radial direction S coating direction U circumferential direction Z shaping step

Claims

Claims

1. Method for shaping a semi-finished product (100) for an electrical contact element (200), in which, in a coating step (B), a coating having Ag as a component, in particular in matrix form, and at least one additional component, is applied to an electrically conductive base body (20) of the semi-finished product (100) in a coating direction (S), the Ag and the additional component being applied in alternating layers (31, 32, 33, 34, 39) comprising at least one Ag layer (31, 39), a layer of the additional component (32, 39) and a second Ag layer (33, 39), in which, in a shaping step (Z) following the coating step (B), the coating (30) is shaped by forming, in particular by stretching the semi-finished product (100) through a orifice (91) or by profile rolling

2. Method according to claim 1, wherein the semi-finished product (100) is a wire (101), in particular a round wire or a profiled wire.

3. Method according to claim 1 or 2, wherein by forming, in particular by drawing or rolling of profile, Ag and the additional component are alloyed.

4. A method according to any one of claims 1 to 3, wherein the additional component is incorporated as particles (40) in an Ag layer.

5. A method according to any one of claims 1 to 4, wherein by forming, in particular by stretching or rolling the profile, a preferred orientation (40) is brought to the particles or a preferred orientation of the particles (40) is changed.

6. Semi-finished product (100) for an electrical contact element (200), comprising an electrically conductive base body (20) and a coating (30) on the base body (20), wherein the coating has Ag as a component, in particular in matrix form, and at least one additional component, wherein the Ag and the additional component are applied in alternating layers (31, 32, 33, 34, 39) comprising at least one Ag layer (31, 39), one layer of the additional component (32, 39) and a second Ag layer (33, 39), and is modified by forming, in particular by profile drawing or rolling.

7. Semi-finished product (100) according to claim 6, wherein Ag and the additional component are mechanically alloyed by forming, in particular by drawing or rolling of profile.

8. Semi-finished product (100) according to claim 6 or 7, wherein at a surface (50) of the semi-finished product (100), crystallites (60) terminate mainly in one or two crystal plane(s), in particular in a plane <111> and / or a plan <110> .

9. Semi-finished product (100) according to any one of claims 6 to 8, wherein the additional component contains at least one material from the group Ni, Pd, Ru, Ti, Mo, W, Fe, Co, or is made of such a material.

10. A semi-finished product (100) according to any one of claims 6 to 9, wherein the additional component contains at least one material from the group consisting of graphene, graphite, carbon nanotubes, sulfides, sulfur sulfide, molybdenum sulfide, tungsten sulfide, hexagonal boron nitride, PTFE, or is made of such a material.

11. A semi-finished product (100) according to any one of claims 6 to 10, wherein the alloy content of the additional component in the coating (30) is 0.3-15%, preferably 0.5-10%.

12. Electrical contact element (200) comprising at least one semi-finished product (100) according to any one of claims 6 to 11.

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