DE102017213586A1 - Methods and compounds for welding dissimilar sheet materials - Google Patents

Abstract

The invention relates to a method for welding a sheet stack comprising a plurality of sheets of different materials. In one aspect, the steel sheets include an aluminum sheet and a hot-galvanized steel sheet. In one aspect, the method includes resistance point welding the hot-galvanized sheet to a hot stamped steel sheet disposed between the aluminum sheet and the hot-galvanized sheet, the hot-galvanized steel sheet including stress relief portions. The method further includes placing a metal foil on the aluminum sheet and vaporizing the metal foil so that portions of the aluminum sheet protrude through the stress relief portions of the hot stamped steel sheet to weld the portions of the aluminum sheet to the galvanized steel sheet. In another aspect, the method includes placing the metal foil on a raised portion of the aluminum sheet and projecting the raised portion of the aluminum onto the hot-galvanized steel sheet.

Description

Cross-reference to related applications

This application claims the benefit of US Provisional Application No. 62/371565, filed on Aug. 5, 2016.

background

The subject matter disclosed herein relates to methods and corresponding compounds for welding dissimilar sheet materials or alloys.

Friction stir welding is widely known as a process for joining multiple aluminum workpieces or sheets together. In friction stir welding, overlaid sheets are joined by pressing a cylindrical tool having a projection at the tip firmly against the overlaid sheets while the tool is rotated, and a portion around the connecting piece by means of the rotational force of the tool plastically Flow is brought and stirred, while the projection of the workpiece penetrates into the sheets and generates frictional heat. This heat melts or welds the sheets together again. Friction stir welding is widely used in various industries that use aluminum workpieces or sheets. For example, friction stir welding may be used for automobile manufacturing.

When applying certain conventional friction stir welding techniques and methods, welding an aluminum sheet to a sheet of different material, for example steel sheet, may be difficult. Current attempts to use conventional resistance punk welding techniques have resulted in stress corrosion cracking and have resulted in welds that are not suitable for structural applications (for example, holding sheets or pieces with welds strong enough to meet, for example, crash test requirements). Accordingly, there remains a need in the art for a process for joining sheets of dissimilar materials, such as aluminum and steel.

Summary

This summary is intended to provide a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features of the claimed subject matter, nor does it serve as an aid in determining the scope of the claimed subject matter.

According to one aspect of the present disclosure, a welding method is provided. The method includes applying a current to a sheet stack for resistance spot welding a first sheet of sheet stack to a second sheet of the sheet pile, the second sheet including at least one cutout. The method also includes placing at least one metal foil on a first side of a third sheet of the sheet stack. The method further includes vaporizing the at least one metal foil so that at least a portion of the third sheet protrudes through the at least a portion of the second sheet from the first sheet to form a weld.

In another aspect of the present disclosure, a welding method is provided. The method includes plating a first sheet of a sheet stack with a transition material. The method also includes raising at least a portion of a second sheet of sheet stack with an angle, wherein the at least one raised portion extends upwardly from an edge of the second sheet. The method further includes placing at least one metal foil on the at least one raised portion of the second sheet. The method includes evaporating the at least one metal foil so that the at least one raised portion of the second plate protrudes onto the first plate.

In another aspect of the present disclosure, a welding method is provided. The method includes applying a current to a stack of sheet metal for resistance sputter welding a first sheet of the sheet stack to a second sheet of the stack of sheets, the second sheet including at least one cutout. The method also includes placing at least one metal foil on a first side of a third sheet of the sheet stack, the third sheet being clad with a transition material. The method further includes vaporizing the at least one metal foil so that at least a portion of the third sheet protrudes through the at least a portion of the second sheet to the first sheet to form a weld.

In another aspect of the present disclosure, a film evaporation actuator weld (VFAW) member is provided. The part includes a first sheet of a sheet stack which is resistance point welded to a second sheet of the sheet stacks at a plurality of weld points, the second sheet including a plurality of cutouts. The part also contains a third sheet of the sheet stack resting on the first sheet by the plurality of Cut-outs welded. A variety of welds and welds in the plurality of cutouts forms a mechanical mesh.

Brief description of the drawings

The novel features believed to be characteristic aspects of the disclosure are set forth in the appended claims. In the following description, like parts throughout the specification and drawings have been given the same reference numerals. The drawings and figures are not necessarily to scale, and certain figures may be shown in emphasized or generalized form for the sake of clarity and consistency. However, the disclosure itself, as well as a preferred embodiment thereof, other objects and advantages thereof, will be best understood by reference to the following detailed description of exemplary embodiments of the disclosure, when read in conjunction with the accompanying drawings, wherein:

1 shows an exemplary vehicle side body panel structure according to various aspects;

2 shows an exemplary sheet stack of different materials to be welded together according to various aspects;

3 shows an exemplary process flow diagram of a welding process according to various aspects;

4 shows an exemplary result of a welding process according to various aspects;

5 FIG. 12 shows an exemplary process flow diagram of a process for film evaporation actuator welding (VFAW) according to various aspects; FIG. and

6 shows an exemplary VFAW welding process according to various aspects.

Detailed description

In general terms, the present disclosure provides a method of welding a sheet stack comprising a plurality of sheets of different materials. In one aspect, the sheet stack includes an aluminum sheet and a hot-galvanized steel sheet. In one aspect, the method may include resistance spot welding the hot-galvanized sheet to a hot stamped steel sheet interposed between the aluminum sheet and the hot-galvanized sheet, the hot stamped steel sheet including stress relief portions. The method may further include disposing a metal foil on the aluminum sheet and vaporizing the metal foil such that portions of the aluminum sheet protrude through the stress relief portions of the hot stamped steel sheet to weld the portions of the aluminum sheet to the galvanized steel sheet. In another aspect, the method may include placing the metal foil on a raised portion of the aluminum sheet and projecting the raised portion of the aluminum onto the hot-galvanized steel sheet without using a spacer (eg, hot stamped steel sheet) between the aluminum sheet and the hot-galvanized sheet ,

1 shows an exemplary vehicle side body part structure 100 , As in 1 shown, the vehicle body side part structure 100 a side sill 13 which extends longitudinally along an outside of a vehicle body (not shown). The side skirts 13 can be a side skirt inner panel 23 included, which forms an inner side surface of the vehicle interior, and a side sill outer panel 31 , with the side of the side skirt inner panel remote from the vehicle interior 23 connected is. The side skirt inner panel 23 may also have an upper rocker inner panel flange 27 included, and the side skirts outer panel 31 may further include an outer sill outer panel flange 35 contain.

In one aspect, the side skirt inner panel may 23 and the side skirts outer panel 31 consist of different sheets. For example, the side skirt inner panel 23 be an aluminum sheet and can the side skirts outer panel 31 to be a steel sheet. However, according to aspects shown herein, the side skirt inner panel may 23 and the side skirts outer panel 31 through welding flanges 27 . 35 the sheets 23 . 31 be connected to each other. It should also be understood that the aspects disclosed herein may also be applied to interconnect other panels of the vehicle body. For example, the aspects shown herein may also be applied to a front pillar 14 to shed a center pillar (not shown) and / or rear pillar (not shown) of the vehicle body.

In relation to 2 is an exemplary sheet pile 210 (For example, flanges) made of different materials according to various aspects. In one aspect, the sheet stack 210 contain at least three individual sheets of different materials. For example, in one aspect, the sheet stack may 210 a hot-galvanized steel sheet 212 included (for example, JAC270 sheet metal or JSC980 sheet metal), which is a first page the sheet pile defined, a hot stamped steel sheet 214 (for example USIBOR ^® 1500P-steel and / or steel 22MnB5) adjacent the hot galvanized sheet 212 , and a sheet of aluminum or aluminum alloy 216 (For example, aluminum 7075 or aluminum alloy A2024), the hot stamped steel sheet 214 is adjacent and a second side of the sheet pile 210 Are defined. In various aspects, an aluminum silicate (AlSi) coating of the hot stamped steel may be used 214 or a zinc (Zn) coating of the hot-galvanized steel 212 be removed to a weld between the hot stamped steel 214 , the hot galvanized steel 212 and / or the sheet of aluminum or aluminum alloy 2166 to improve. For example, the AlSi coating of hot stamped steel 214 or the Zn coating of the hot-galvanized steel 212 be removed mechanically, for example by laser ablation. Alternatively or additionally, the aluminum or the aluminum alloy 216 plated with a transition metal, such as Alum 1100 to make a weld between the hot stamped steel 212 , the hot galvanized steel 212 and / or the sheet of aluminum or aluminum alloy 216 to improve.

Although three individual sheets are illustrated and described herein, the above teachings may also be readily applied to sheet stacks having more than three individual sheets, including four sheets, five sheets, six sheets, or even more or fewer sheets.

In one aspect, multiple sections of the hot stamped steel sheet may be used 214 from the edge of the sheet 214 be cut to make it easier and / or to provide clearance / gap to improve the quality of welding. For example, in one aspect, a plurality of relief sections (eg, two relief sections 220a . 220b ) from one edge of the hot stamped steel sheet 214 be cut away. In one aspect, the cutouts 222a . 222b for example, be semi-circular cutouts.

In relation to 3 becomes a procedure 300 for welding steel sheets of different materials according to various aspects. 3 is related to the components of 2 described. In one aspect, the method 300 in the block 302 containing an aluminum silicate (AlSi) coating of hot stamped steel 214 or a zinc (Zn) coating of the hot-galvanized steel 212 to remove. For example, the AlSi coating of hot stamped steel 214 or the Zn coating of the hot-galvanized steel 212 be removed mechanically, for example by laser ablation. Alternatively or additionally, the method 300 in the block 302 containing aluminum or aluminum alloy 216 to clad with a transitional material. In one aspect, the method 300 in the block 304 to apply power to a stack of laminations to spot weld a first sheet to a second sheet (RSW). In one aspect, the hot-galvanized steel sheet may 212 on the hot stamped steel sheet 214 resistance point welded by the current to an outer surface of the hot-galvanized steel sheet 212 is created at several points. In one aspect, the hot-galvanized steel sheet may 212 to the hot stamped steel sheet 214 at every point 224 adjacent or between the plurality of relief sections 222a . 222b of the hot stamped steel sheet 214 resistance point welded. For example, in one aspect, an interior surface of the hot-galvanized steel sheet may 212 to a surface of the hot stamped steel sheet 214 adjacent to the hot-galvanized steel sheet 212 at each of the points 224 resistance point welded.

In block 306 can the procedure 300 contain, at least to arrange a metal foil on a third sheet. In one aspect, a strip of metal foil 232 on an outer surface of the aluminum sheet 216 opposite each of the plurality of relief sections 222a . 222b of the hot stamped steel sheet 214 to be ordered.

In block 308 For example, the method may include vaporizing at least one metal foil such that at least a portion of the third sheet protrudes through the second sheet toward the first sheet. In one aspect, each metal foil strip 323 be evaporated, so that at least a portion of the aluminum sheet 216 through the hot stamped steel sheet 214 to hot-galvanized sheet steel 212 protrudes. In one aspect, every metal strip 232 be evaporated by applying a strong electric current (for example of the order of 4 to 10 kJ) through each of the metal foils 232 is directed. When the metal foils 232 can be evaporated, reaction forces to the aluminum sheet 216 be aligned, and a portion of the aluminum sheet 216 can through each of the relief sections 222a . 222b of the hot stamped steel sheet 214 and into the hot-galvanized sheet steel 212 protrude to a weld between the inner surface of the aluminum sheet 216 and the inner surface of the hot-galvanized steel sheet 212 to build.

In relation to 4 is an exemplary result 400 of the procedure 300 ( 3 ). As described above, in one aspect, the hot stamped steel sheet may 214 to the hot-galvanized sheet steel 212 at points 224a . 224b . 224c resistance point welded. Moreover, in one aspect, each of the metal foils 232 (in 2 ) are evaporated, leaving sections of the aluminum sheet 216 through relief sections 402 . 404 (see for example relief sections 222a . 222b ) ( 2 ) protrude. As a result of the protrusion, the aluminum sheet 216 to the hot-galvanized sheet steel 212 in the discharge sections 402 . 404 be welded. It is understood that the variety of spot welds 224a . 224b . 224c and the welds in the relief sections 402 . 404 , forms a mechanical interlock suitable for structural use.

Now, in terms of 5 and 6 an exemplary film evaporation actuator welding (VFAW) process 500 described in various aspects. In one aspect, the aluminum sheet 616 and the hot-galvanized sheet steel 612 welded together without a spacer (for example, a hot punched steel sheet 214 ) ( 1 ) between the sheets 612 . 616 to use. In one aspect, the method 500 at the block 502 include a zinc (Zn) coating of the hot-galvanized steel 612 to remove. For example, the Zn coating of the hot-galvanized steel 612 be removed mechanically, for example by laser ablation.

Alternatively or additionally, in block 502 the procedure 300 include, the aluminum 616 to clad with a transitional material. In one aspect, the method 500 in the block 504 include raising at least a portion of a first sheet at an angle. For example, in one aspect, at least one hinged or raised portion may be in the aluminum sheet 616 be formed. The raised section may be from the edge of the aluminum sheet 616 extend upward at an angle such as, but not limited to, 10 to 30 degrees.

In block 506 may include the method of arranging at least one metal foil on the at least one raised portion of the first sheet. For example, in one aspect, a strip of metal foil 604 on an outer surface of the raised portion of the aluminum sheet 616 to be ordered.

In block 508 can the procedure 500 to evaporate the at least one metal foil so that the at least one raised portion of the first sheet projecting onto a second sheet. For example, in one aspect, the metal foil 604 be evaporated so that part of the raised portion of the aluminum sheet 616 to hot-galvanized sheet metal 612 protrudes, leaving a weld 602 between an inner surface of the aluminum sheet 616 and an inner surface of the hot-galvanized sheet 612 is formed. In this case, the weld may extend all the way to the edge of the hot-galvanized steel sheet 612 extend. Moreover, it should also be understood that forming the raised portion provides a more consistent weld (eg, no "donut" shape) between the sheets 612 . 616 allowed.

The methods and corresponding devices have been described so that a sheet stack of different materials with two or more individual sheets can be reliably welded. The described methods and apparatus provide an economical, flexible and efficient welding solution that does not require the expense and expense associated with using a specialized welding apparatus and / or replacement of most existing welding machines.

The foregoing description of embodiments and examples has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the forms described herein. Numerous modifications are possible in light of the above teachings. Some of these modifications have been discussed, others will be understood by those skilled in the art. The designs have been selected and described to illustrate various designs. The scope, of course, is not limited to the examples or embodiments set forth herein, but may be applied by those skilled in any number of applications and equivalent devices. Instead, the scope should be defined by the appended claims. Moreover, the features of the various embodiments may be combined to form further embodiments of the disclosure.

The invention relates to a method for welding a sheet stack comprising a plurality of sheets of different materials. In one aspect, the steel sheets include an aluminum sheet and a hot-galvanized steel sheet. In one aspect, the method includes resistance point welding the hot-galvanized sheet to a hot stamped steel sheet disposed between the aluminum sheet and the hot-galvanized sheet, the hot-galvanized steel sheet including stress relief portions. The method further includes placing a metal foil on the aluminum sheet and vaporizing the metal foil so that portions of the aluminum sheet protrude through the stress relief portions of the hot stamped steel sheet to weld the portions of the aluminum sheet to the galvanized steel sheet. In another aspect, the method includes placing the metal foil on a raised portion of the aluminum sheet and projecting the raised portion of the aluminum onto the hot-galvanized steel sheet.

Claims (18)

Welding method, which comprises Applying a current to a sheet stack to resistively weld a first sheet of the sheet stack to a second sheet of the stack of sheets, the second sheet including at least one cutout; Arranging at least one metal foil on a first side of a third sheet of the sheet stack; and Vaporizing the at least one metal foil so that at least a portion of the third sheet protrudes through the at least a portion of the second sheet to the first sheet to form a weld. The method of claim 1, further comprising at least one of: Removing a first coating from the first sheet; Removing a second coating from the second sheet; or Plating the third sheet with a transitional material. The method of claim 1, wherein the application of the stream further comprises: Applying the current to the sheet stack to resistively weld a first side of the first sheet to a first side of the second sheet. The method of claim 1, wherein vaporizing the at least one metal foil further comprises: Forming the weld between the first side of the third sheet and a second side of the first sheet. The method of claim 1, further comprising arranging at least a portion of the second sheet at an edge of the second sheet. Welding method, which comprises Plating a first sheet of a sheet stack with a transition material; Raising at least a portion of a second sheet of sheet stack with an angle, the at least one raised portion extending upwardly from an edge of the second sheet; Arranging at least one metal foil on the at least one raised portion of the second sheet; and Vaporizing the at least one metal foil so that the at least one raised portion of the second plate protrudes onto the first plate. The method of claim 6, wherein disposing the at least one metal foil comprises arranging a strip of the at least one metal foil on an outer surface of the at least one raised portion of the second plate. The method of claim 6, wherein vaporizing the at least one metal foil comprises forming a weld between an inner surface of the first sheet and an inner surface of the second sheet. The method of claim 6, wherein vaporizing comprises the at least one metal foil evaporating the at least one metal foil to project a second side of the first sheet onto the second sheet of the sheet stack. The method of claim 6, wherein the lifting of the at least a portion of the second sheet comprises raising at least the portion of the second sheet at an angle between 10 and 30 degrees. Welding method, which comprises Applying a current to a sheet stack to resistively weld a first sheet of the sheet stack to a second sheet of the stack of sheets, the second sheet including at least one cutout; Arranging at least one metal foil on a first side of a third sheet of the sheet stack, the third sheet being clad with a transition material; and Vaporizing the at least one metal foil so that at least a portion of the third sheet protrudes through the at least one cutout of the second sheet to the first sheet to form a weld. The method of claim 11, further comprising at least one: Removing a first coating from the first sheet; or Removing a second coating from the second sheet. The method of claim 11, wherein the application of the stream further comprises: Applying the current to the sheet stack to resistively weld a first side of the first sheet to a first side of the second sheet. The method of claim 11, wherein vaporizing the at least one metal foil further comprises: Forming the weld between the first side of the third sheet and a second side of the first sheet. The method of claim 11, further comprising disposing the at least a portion of the second sheet at an edge of the second sheet. Foil Evaporation Actuator Welding (VFAW) part, comprising: a first sheet of a stack of sheet metal that is resistance point welded to a second sheet of the stack of sheets at a plurality of weld points, the second sheet including a plurality of cutouts; a third sheet of the stack of sheets welded to the first sheet by the plurality of cutouts with a variation of the welds and welds in the plurality of cutouts to form a mechanical interlock. The part of claim 16, wherein: the first sheet has a first kind of steel; the second sheet has a second type of steel; and the third sheet of aluminum. The part of claim 17, wherein: the first steel type is a hot galvanized steel, and the second steel type is a hot stamped steel.

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