Deterministic Surface Sheet Steel for Homogeneous Lubricant Wetting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of stochastic surface structures on steel sheets coated with zinc-based coatings leads to uneven surface chemistry during tempering, resulting in inhomogeneous distribution of lubricants, increased lubricant usage, and environmental and safety concerns, particularly in automobile component production.
Innovation Solution
A steel sheet with a deterministic surface structure is coated with a zinc-based coating, where the surface chemistry is modified to have a higher concentration of zinc in valley areas and magnesium-rich oxide layers in mountain areas, enhancing wetting properties and reducing lubricant usage by designing the surface structure to attract lubricants to flank areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If a stochastic surface structure is used on zinc-coated steel sheets, then the surface provides some lubricant retention capability, but the surface chemistry becomes uneven during tempering resulting in inhomogeneous lubricant distribution
Solution Approach 1:
The patent applies local quality by creating distinct surface regions with different chemical compositions - zinc-rich valley areas for lubricant retention and alloying element-rich mountain areas for other functions. This localized differentiation ensures homogeneous lubricant distribution while maintaining functional surface properties.
Solution Approach 2:
The surface structure is segmented into distinct mountain and valley areas with different chemical compositions. The valley areas are specifically enriched with zinc to create lubricant pockets, while mountain areas contain higher concentrations of alloying elements, achieving homogeneous lubricant distribution through structural segmentation.
2Ease of operation
If additional lubrication is applied to reduce frictional forces during forming, then the material flow control is improved, but the cleaning effort and environmental impact increase
Solution Approach 1:
The steel sheet surface structure itself provides the lubrication function through zinc-rich valley areas that retain and supply lubricant during forming. This self-service approach eliminates or reduces the need for additional external lubrication, thereby reducing cleaning efforts and environmental impact while maintaining good material flow control.
Solution Approach 2:
The zinc-rich valley areas on the surface act as an intermediary that provides lubricant retention and supply, mediating between the sheet surface and the forming process. This built-in intermediary reduces dependence on external lubricants, decreasing environmental harm while maintaining ease of operation.
3Manufacturing precision
If the bearing area of the tempering roller is increased to improve forming properties, then more lubricant is required to cover the increased surface area
Solution Approach 1:
Instead of uniformly distributing lubricant across the entire surface, the patent creates zinc-rich valley areas specifically positioned to retain and supply lubricant where needed. This localized quality approach ensures adequate lubrication for improved forming properties without proportionally increasing overall lubricant consumption.
Solution Approach 2:
The zinc-rich valley areas function similarly to porous structures by providing lubricant retention pockets. These localized porous-like regions hold lubricant and release it during forming, enabling good forming properties with reduced overall lubricant consumption compared to uniform surface coverage.
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 approach ensures homogeneous lubricant distribution, reduces lubricant consumption, and improves forming processes by targeting lubricant application to relevant areas, enhancing both environmental sustainability and process efficiency.
Implementation Method 1
The mechanical stress during tempering can cause the zinc to be exposed at the contact points between the tempering roller and the sheet metal, instead of the alloying elements
Implementation Method 2
The wettability of sheet metal by both aqueous media and lubricants relevant to the forming process depends not only on the sheet topography. Local wettability is also influenced by the surface chemistry.
Data Source
Figure 1~2b
Figure 3
AI summary
The invention relates to sheet steel (1) which is coated by a zinc-based coating and skin pass rolled to have a deterministic surface structure (2), and to a method for the production thereof.