CN105136589A - Method for testing forming limit of tailor welded blank during metal plate incremental forming - Google Patents

Abstract

The present invention discloses a method for testing forming limit of a tailor welded blank during metal plate incremental forming, a part model needed by forming is constructed in three-dimensional modeling software, and a numerical control code is generated; the tailor welded blank is mounted between a fixture support plate and a pressure plate, and the weld joint offset position can be determined by marking on the support plate; a tool head is used for forming a plate, when the weld joint ruptures, the processing is stopped, and the depth of the rupture position is measured; according to the rupture depth, an included angle of a weld joint tangent line and a first principal strain position in the rupture position can be read out in the model, and the relation curve of the included angle and the forming angle can be drawn. The method for testing the forming limit of the tailor welded blank during metal plate incremental forming is simple in operation steps; the data needed to draw the curve can be obtained by forming of a small amount of the plate; and the rupture forming Phi- Theta diagram can provided a basis for testing the forming limit of the tailor welded blank during metal plate incremental forming.

Description

A kind of tailor welded forming limit method of testing in metal blank progressive molding

Technical field

The present invention relates to a kind of tailor welded forming limit method of testing in metal blank progressive molding, belong to Sheet metal forming technical field.

Background technology

A kind of Flexible Manufacturing Technology being applicable to single-piece, short run panel beating product of metal blank progressive molding technology.This technology, by the thought of " Layered manufacturing ", adopts forming tool head under the control of digital control system, do level line motion, is successively shaped by plate.This manufacturing process eliminates high Making mold expense, makes the production of panel beating product achieve digitizing and customization.

Tailor welded has been widely used in the field such as automobile, Aero-Space at present.The major advantage of tailor welded: intensity and the weight that simultaneously can take into account sheet metal part, because the sheet thickness of tailor welded weld seam both sides is inconsistent, therefore can be used in the side higher to requirement of strength according to requirements by slab.Like this, for whole part, slab side can ensure that part has enough intensity, and thin plate side then reduces the weight of part.

At present, the research about tailor welded progressive molding is less, and result of study shows, affect quality of weld seam molding because have following 2 points: bead direction is with the angle of the first principal strain directions and the distortion of weld seam.If angle is excessive with distortion, breaking of weld seam can be caused.Therefore, propose a kind of method of testing measuring tailor welded forming limit in progressive molding, this two factor over-limit condition can be avoided in the design process, avoid the waste causing material and man-hour in forming process.

Summary of the invention

Object: in order to overcome the deficiencies in the prior art, the invention provides a kind of tailor welded forming limit method of testing in metal blank progressive molding.

Technical scheme: for solving the problems of the technologies described above, the technical solution used in the present invention is:

A kind of tailor welded forming limit method of testing in metal blank progressive molding, comprises the steps:

Step one: set up multiple part model in CAD/CAM software, described part model is set to the conical part model of differing formed angle, and described shape angles is set to θ, and according to conical part model generation numerical control code;

Step 2: settle plate on progressive molding lathe, for the conical part of differing formed angle, welding seam distance conical part center line arranges different side-play amount;

Step 3: start lathe shaping conical part, stop processing when weld seam breaks; Each conical part, is at least shaped three times;

Step 4: measure weld seam breakdown point degree of depth h, and read the included angle of weld seam breakdown point tangential direction and the first principal strain directions in cad model, described first principal strain directions is set to conical part generatrix direction;

Step 5: gather θ, φ test figure, obtains φ-θ curve;

Step 6: actually add man-hour, any θ, φ value in contrast part model weld seam, as appear at paint below φ-θ curve time, represent this some safety in forming process, otherwise then can break.

Described conical part model top diameter is set to 110mm, and described differing formed angle θ is set to 50 ° or 55 ° or 60 ° respectively.

The different side-play amount of described welding seam distance center line is set to 30mm or 28mm or 25mm respectively.

Preferably, described part model is set to complex parts model, and the weld seam of described complex parts model is projected as curve along Z-direction, and complex parts profile is complex-curved; Then θ, φ obtaining step is as follows:

Step one: import complex parts model in CAD software, according to the ultimate principle of progressive shape detrusion, after being shaped, weld shape is original shape along the projection of Z-direction on model sidewall; Then multiple sampling spot is chosen in welded joints, for a sampling spot, did the surface level of sampling spot, the intersection of model, then intersection is projected on the section of sampling spot, section is crossed the vertical line that sampling spot does intersection projection line, obtain the first principal strain directions, the angle of the first principal strain directions and sampling spot place weld seam tangent line is φ angle;

Step 2: sampling spot place normal direction is θ angle with Z axis angle;

Step 3: get different sampling spot, obtains the value of θ, φ respectively, draws φ-θ curve.

Beneficial effect: a kind of tailor welded provided by the invention forming limit method of testing in metal blank progressive molding, simple operating steps; Only need the data that the shaping carrying out a small amount of plate just can obtain required for curve plotting; What the design obtained break, and shaping φ-θ figure can provide foundation for the forming limit of tailor welded in metal blank progressive molding measures, and has filled up the blank of research work in the past.

Accompanying drawing explanation

Fig. 1 is metal blank vertical view of the present invention;

Fig. 2 is metal blank progressive molding machining sketch chart of the present invention;

Fig. 3 is weld seam breakdown point of the present invention and the first principal strain directions angle schematic diagram;

Fig. 4 is φ-θ curve synoptic diagram of the present invention;

Fig. 5 is that complex parts model φ angle of the present invention judges schematic diagram;

Fig. 6 is that weld seam after complex parts molder of the present invention, initial weld seam are along Z-direction projection relation figure.

Embodiment

Below in conjunction with accompanying drawing, the present invention is further described.

A kind of tailor welded forming limit method of testing in metal blank progressive molding mainly comprises test and the work of digital independent two parts.

Specifically comprise the steps:

Step one: build the geometric model being shaped and needing in 3D sculpting software, as the conical part of differing formed angle θ;

Step 2: as shown in Figure 1, 2, clamp base 1 is arranged on progressive molding platen, then back up pad 2, pressing plate 3 are placed successively, back up pad 2 is rule, determine weld seam 6 side-play amount l, in the middle of back up pad 2 and pressing plate 3, place plate 4, during placement, weld seam 6 need aim at the line in back up pad 2.With fastening bolt, back up pad 2 and pressing plate 3 are fixed in clamp base 1.Touch the inward flange of pressing plate 3 and the upper surface of plate 4 with forming tool head 5, set up shaping coordinate system;

Step 3: the numerical control machining code generating all models in the first step, and import progressive molding lathe;

Step 4: carry out progressive molding by tool heads 5 pairs of plates 4, measure weld seam breakdown point degree of depth h after weld seam 6 breaks;

Step 5: according to the ultimate principle of progressive shape detrusion, after being shaped, weld seam 6 shape is its initial weld shape along the projection of Z-direction on model sidewall; As shown in Figure 3, in cad model, measure weld seam breakdown point tangent line 8 direction with the first principal strain directions 7(model generatrix direction) included angle;

Step 6: gather test figure, as shown in Figure 4, draws φ-θ curve.

As shown in Figure 5, if processed complex part model, weld seam 6 is projected as curve along Z-direction, and when part profile is complex-curved, θ, φ obtaining step is as follows:

Step one: import complex parts model in CAD software, according to the ultimate principle of progressive shape detrusion, as shown in Figure 6, after being shaped, weld seam 6 shape is its original shape along the projection of Z-direction on model sidewall; Then on weld seam 6, some sampling spots are chosen, for a certain sampling spot, did the surface level 9 of sampling spot and the intersection 10 of model, then intersection 10 is projected on the section of sampling spot, section is crossed the vertical line 11 that sampling spot does intersection 10 projection line, vertical line 11 direction is the first principal strain directions, and the angle of the first principal strain directions and sampling spot place weld seam tangent line 12 is φ angle;

Step 2: sampling spot place normal direction is θ angle with Z axis angle;

Step 3: get different sampling spot, obtains the value of θ, φ respectively, draws φ-θ curve.

During actual use, but θ, φ value that in model to be processed, in weld seam, certain is put, when appearing at below painted φ-θ curve, represent this some safety in forming process, otherwise then can break.

The above is only the preferred embodiment of the present invention; be noted that for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (4)

1. tailor welded forming limit method of testing in metal blank progressive molding, is characterized in that: comprise the steps:

Step one: set up multiple part model in CAD/CAM software, described part model is set to the conical part model of differing formed angle, and described shape angles is set to θ, and according to conical part model generation numerical control code;

Step 2: settle plate on progressive molding lathe, for the conical part of differing formed angle, welding seam distance conical part center line arranges different side-play amount;

Step 3: start lathe shaping conical part, stop processing when weld seam breaks; Each conical part, is at least shaped three times;

Step 4: measure weld seam breakdown point degree of depth h, and read the included angle of weld seam breakdown point tangential direction and the first principal strain directions in cad model, described first principal strain directions is set to conical part generatrix direction;

Step 5: gather θ, φ test figure, obtains φ-θ curve;

Step 6: actually add man-hour, any θ, φ value in contrast part model weld seam, as appear at paint below φ-θ curve time, represent this some safety in forming process, otherwise then can break.

2. a kind of tailor welded according to claim 1 forming limit method of testing in metal blank progressive molding, it is characterized in that: described conical part model top diameter is set to 110mm, described differing formed angle θ is set to 50 ° or 55 ° or 60 ° respectively.

3. a kind of tailor welded according to claim 1 forming limit method of testing in metal blank progressive molding, is characterized in that: the different side-play amount of described welding seam distance center line is set to 30mm or 28mm or 25mm respectively.

4. a kind of tailor welded according to claim 1 forming limit method of testing in metal blank progressive molding, it is characterized in that: described part model is set to complex parts model, the weld seam of described complex parts model is projected as curve along Z-direction, and complex parts profile is complex-curved; Then θ, φ obtaining step is as follows:

Step one: import complex parts model in CAD software, according to the ultimate principle of progressive shape detrusion, after being shaped, weld shape is original shape along the projection of Z-direction on model sidewall; Then multiple sampling spot is chosen in welded joints, for a sampling spot, did the surface level of sampling spot, the intersection of model, then intersection is projected on the section of sampling spot, section is crossed the vertical line that sampling spot does intersection projection line, obtain the first principal strain directions, the angle of the first principal strain directions and sampling spot place weld seam tangent line is φ angle;

Step 2: sampling spot place normal direction is θ angle with Z axis angle;

Step 3: get different sampling spot, obtains the value of θ, φ respectively, draws φ-θ curve.