Press Hardening Tool Perforation Geometry Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing press hardening methods for producing sheet metal components with perforations face issues of irregular shrinkage and changes in peripheral geometry due to the hardening process, particularly when using laser machining, which is costly and affects the achieved hardness.
Innovation Solution
A press hardening tool with a return stamp that allows the punched out piece to be fed back into the perforation during the quenching process, ensuring uniform shrinkage and maintaining the original geometry by acting as a place holder until the end of the quenching process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If laser machining is used to produce perforations in hardened sheet metal components, then the perforations can be produced after hardening, but the hardness is decreased at the marginal areas and the costs increase
Solution Approach 1:
The perforation is produced in the blank before the hardening process takes place, while the material is still in its soft state. This preliminary action allows the perforation to be created without the limitations of hardened material, avoiding the need for expensive laser machining and preventing hardness degradation at the margins.
2Object-generated harmful factors
If the punched out piece is removed immediately after producing the perforation, then damage to the punching stamp is avoided, but irregular shrinkage of the perforation opening width occurs during quenching
Solution Approach 1:
The punched out piece serves as a temporary intermediary or placeholder within the perforation during the quenching process. It mediates between the need to protect the punching stamp and the need to maintain perforation geometry, preventing irregular shrinkage by occupying the space that would otherwise collapse. After quenching completes, the piece is removed and the perforation is cleaned.
3Manufacturing precision
If the punched out piece remains in the perforation during quenching, then uniform shrinkage and geometry are maintained, but the punching stamp may be damaged by shrunk material
Solution Approach 1:
The process is segmented into distinct phases: first the perforation is produced and the piece is immediately removed to prevent stamp damage, then the piece is reintroduced as a placeholder before quenching begins, and finally after quenching the piece is removed again and the perforation is cleaned. This segmentation allows each phase to optimize for its specific requirement without compromising the other.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively prevents irregular shrinkage and maintains the desired geometry of the perforation, ensuring uniform quenching conditions and preserving the hardness of the sheet metal component without material loss or bonding issues.
Implementation Method 1
a blank is heated to forming temperature
Implementation Method 2
cooled sufficiently rapidly for it to harden and thus be tempered
Data Source
AI summary
The invention relates to a method for producing a shaped and at least regionally hardened sheet metal component, particularly a sheet steel component (15), with at least one perforation (16) produced in it, in which method a preform (13) is heated to forming temperature, subsequently shaped and then at least regionally hardened by corresponding cooling, wherein the at least one perforation (16) in the preform (13) is produced during the course of a punching process before the preform (13) is hardened. According to the invention, the metal piece (14) separated from the preform (13) by punching is fed back to its original position or a corresponding position in the perforation (16), remains there for the duration of the quenching process and is only pressed out during or after removal of the sheet steel component (13) from the die (1), in which it is held during quenching. The invention also describes a quench press die (1) for producing a shaped and at least regionally hardened sheet metal component, particularly a sheet steel component (15), with at least two die parts (2, 3) adjustable against one another for opening and closing the die (1) and with a punching device (7) comprising a punching die (8) for producing a perforation (16) in a preform (13) located between the die parts (2, 3). The die part (2), against which the punching die (8) for producing the perforation (16) works, has a return punch (11), the actuation side of which points towards the punching die (8) and the axis of motion of which corresponds to the axis of motion of the punching die (8), such that a metal piece (14) separated from a preform (13) by means of said punching die (8) can be returned to the correct position, or approximately to the correct position in the perforation (16) produced in the preform (13) by the punching process to fill said perforation.