METHOD FOR PRODUCING A COMPONENT BY FURTHER FORMING A PREFORMED CONTOUR

Abstract

In a method for producing a component by further forming of a preformed contour of a blank, the blank which has previously been cut to size at ambient temperature from a strip or a metal sheet undergoes after optional further manufacturing steps carried out at ambient temperature, e.g. punching or cutting operations to realize recesses or openings, in selected edge regions that have been strain hardened by the punching or cutting operations to obtain a preformed contour a first forming operation at ambient temperature. The edge regions intended to undergo the forming operation or at least the edge regions that have undergone the first forming operation are heated to a temperature of at least 600 C. for maximal 10 seconds. After the heat treatment, the edge regions undergo at any time a second forming operation or further forming operations at ambient temperature with respectively preceding heat treatments.

Claims

1.-17. (canceled)

18. A method for producing a component, said method comprising: subjecting a blank that has been cut to size beforehand at ambient temperature from a strip or metal sheet to a manufacturing step to thereby produce a recess or opening; subjecting the recess or opening to a first forming operation at ambient temperature to produce a preformed contour with an edge region that became strain hardened as a result of the manufacturing step; heating an edge region of the recess or opening or at least the edge region that was subjected to the first forming operation to a temperature of at least 600 C. for a period of maximal 10 seconds; and subjecting the edge region after being heated at any time to a second forming operation or further forming operations at ambient temperature, with each of the further forming operations being preceded by a heat treatment.

19. The method of claim 18, wherein the manufacturing step includes a punching or cutting operation.

20. The method of claim 18, further comprising preforming the strip or metal sheet, from which the blank used for the production of the component is cut to size, in a pretreatment step prior to the first forming operation.

21. The method of claim 18, wherein the component is obtained by the second forming operation.

22. The method of claim 18, wherein after the second forming operation any number of further forming steps of the edge region are carried out at ambient temperature, wherein each of the further forming steps is preceded by a further temperature treatment of the edge region at at least 600 C. for a period of maximal 10 seconds.

23. The method of claim 18, wherein the edge region undergoing the first forming operation is heated to a temperature of at least 600 C. for a period of 0.02 to 10 seconds.

24. The method of claim 18, wherein the edge region undergoing the first forming operation is heated to a temperature of at least 600 C. for a period of 0.1 to 2 seconds.

25. The method of claim 18, wherein the edge region undergoing the first forming operation is heated to a temperature of 600 C. to a solidus temperature.

26. The method of claim 18, wherein the edge region undergoing the first forming operation is heated to a temperature from a transformation temperature Ac1 to a solidus temperature.

27. The method of claim 18, wherein heating of the edge region to a temperature of at least 600 C. is implemented inductively, conductively, by radiation heating or by laser radiation.

28. The method of claim 18, wherein the blank has an organic and/or metallic coating.

29. The method of claim 28, wherein the metallic coating contains Zn, Mg, Al and/or Si.

30. The method of claim 18, wherein a heat treatment of the blank, starting from an edge, takes place in a region which corresponds at most to a thickness of the blank.

31. The method of claim 18, further comprising flushing an area about the edge region with inert gas during and optionally before and/or after undergoing heat treatment for protection against oxidation.

32. The method of claim 18, wherein the metal sheet is made from a steel comprising a following alloy composition in wt.-%: TABLE-US-00002 C 0.01-0.2% Si 0.2-4.0% Mn 0.5-4.0% Al 0.02-0.1 Ti 0.0-0.2 V 0.0-0.3 Nb 0.0-0.1 with optional addition of Cr, Ni, Mo, B, balance iron, including impurities resulting from smelting.

33. A method, comprising: cutting a blank from a strip or a metal sheet of steel at ambient temperature; subjecting the blank to a manufacturing step to thereby produce a recess or opening; subjecting the recess or opening to a first forming operation at ambient temperature to produce a preformed contour with an edge region that became strain hardened as a result of the manufacturing step; heating the edge region that was subjected to the first forming operation to a temperature of at least 600 C. for a period of maximal 10 seconds; and subjecting the edge region after being heated at any time to a second forming operation at ambient temperature, thereby enabling the blank to be used in the production of a component.

34. The method of claim 33, wherein the edge region undergoing the first forming operation is heated to a temperature of at least 600 C. for a period of 0.02 to 10 seconds.

35. The method of claim 33, wherein the edge region undergoing the first forming operation is heated to a temperature of at least 600 C. for a period of 0.1 to 2 seconds.

Description

[0055] Further features, advantages and details of the invention will become apparent from the following description of FIG. 1, which shows a schematic illustration of the individual steps of the method according to the invention.

[0056] The left-hand image of FIG. 1 shows the optional preforming of a blank already cut to size by shear cutting. The second image from the left in FIG. 1 shows the punching of a hole in the blank (step 1). The cutting edges of the hole are then optionally subjected to a heating according to the invention (step 1a). The method according to the invention furthermore includes the subsequent forming of the blank in the edge regions thereof into a preformed contour, for example, to an incomplete collar (step 2).

[0057] As the thus-obtained preformed contour has in the shear-affected edge regions a high strain hardening that would possibly lead during further forming operation to defects in the material, the edge regions then undergo the temperature treatment in accordance with the invention of at least 600 C. for a period of up to 10 seconds for elimination or reduction of the strain hardening (step 3).

[0058] As a consequence of the temperature treatment, the component recovers also in the stressed edge regions its formability to a considerable extent, so that in the next step, a new, further forming operation can take place (step 4).

[0059] In embodiments in which the desired component has not yet been obtained by the second forming operation, the material stress generated by the second forming operation can be eliminated, at least partially, by a subsequent temperature treatment of at least 600 C. for a period of maximal 10 seconds, whereupon a third forming step can take place. Should the desired result not be achieved as a result of the third forming step, the steps of the temperature treatment of at least 600 C. for a period of maximal 10 seconds, followed by a subsequent forming step at room temperature, may be repeated as often as desired.

[0060] The features of the invention disclosed in the preceding description, in FIG. 1 and in the claims can be essential individually as well as in any combinations for the realization of the invention in its various embodiments.