Metal Composite Structure with Neutral Axis in Adhesive Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional side sill structures in vehicles, which include an adhesive layer between reinforcing members and a sheet member, tend to separate at the adhesive layer during a side collision before the reinforcing members or sheet member breaks, resulting in an insufficient reinforcing effect.
Innovation Solution
A metal composite structure comprising a thin steel sheet, a low-specific-gravity sheet material, and an adhesive layer, where the sheet thicknesses are set to satisfy specific equations for bending rigidity and inequality conditions, ensuring the neutral axis is within the adhesive layer or at its interfaces, thereby enhancing the reinforcing effect without separation at the adhesive layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If an adhesive layer is interposed between reinforcing members and sheet member, then ease of manufacture is improved, but separating at adhesive layer occurs during collision before member breakage
Solution Approach 1:
The patent applies parameter changes by precisely controlling the thickness of the adhesive layer and the sheet members, and by adjusting the neutral axis position through specific thickness ratios. This transforms the adhesive layer from a weak point into a structural component that maintains integrity during collision, resolving the contradiction between ease of manufacture and reinforcing effect.
Solution Approach 2:
The patent creates a composite structure where the adhesive layer, thin steel sheet, and low-specific-gravity sheet material work together as an integrated system. The composite design ensures that the adhesive layer remains functional during collision by positioning the neutral axis within or at the interface with the adhesive layer, preventing separation while maintaining manufacturing advantages.
2Weight of moving object
If thin steel sheet and low-specific-gravity sheet material are used, then vehicle body weight is reduced, but bending rigidity must be maintained
Solution Approach 1:
The patent combines thin steel sheet and low-specific-gravity sheet material into a composite structure that achieves optimal weight-strength balance. The adhesive layer is strategically positioned to maintain structural integrity while allowing the use of lighter materials, thus reducing vehicle body weight without compromising bending rigidity.
Solution Approach 2:
The patent optimizes the thickness parameters of the sheet members and adhesive layer to satisfy specific equations that ensure adequate bending rigidity. By carefully controlling these parameters, the structure achieves the required strength while minimizing weight, resolving the contradiction between weight reduction and rigidity maintenance.
3Strength
If adhesive layer thickness is increased, then bonding strength is improved, but neutral axis position shifts affecting structural efficiency
Solution Approach 1:
The patent establishes specific thickness ratios and equations that control the adhesive layer thickness and neutral axis position. This parameter optimization ensures that the adhesive layer provides sufficient bonding strength while maintaining structural efficiency, preventing the neutral axis from shifting to positions that would reduce overall structural performance.
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
The metal composite structure achieves a superior reinforcing effect while including an adhesive layer, contributing to reduced vehicle body weight for enhanced collision safety, and exhibits high bending rigidity and improved buckling strength.
Implementation Method 1
an adhesive layer bonding the thin steel sheet and the low-specific-gravity sheet material
Implementation Method 2
a bending rigidity D of the metal composite structure... E1 is a longitudinal elastic modulus of the thin steel sheet, E2 is a longitudinal elastic modulus of the low-specific-gravity sheet material
Data Source
AI summary
A metal composite structure includes: a thin steel sheet; a low-specific-gravity sheet material having a lower specific gravity than the thin steel sheet and a lower strength than the thin steel sheet; and an adhesive layer which bonds the thin steel sheet and the low-specific-gravity sheet material and has a lower strength than the thin steel sheet and the low-specific-gravity sheet material, wherein a sheet thickness of the thin steel sheet and a sheet thickness of the low-specific-gravity sheet material are set so that a neutral axis of the metal composite structure is located in the adhesive layer for a bending rigidity set in advance for the metal composite structure, based on an equation representing the bending rigidity.