Welded Blank Assembly With Coating-Free Notch for Stronger Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Coating materials on high-strength steel alloys can contaminate welds during the welding process, reducing weld strength and integrity, especially in butt or lap welding configurations.
Innovation Solution
The method involves providing sheet metal pieces with a base material layer of boron steel or press hardenable steel, an aluminum-based coating material layer, and a weld notch along the edge region where the coating material is removed, allowing for the formation of a weld pool that incorporates additional material to enhance the hardness and tensile strength of the weld joint through heat treatment.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sheet metal pieces with aluminum-based coating material layers are welded together, then corrosion and scaling resistance is improved, but weld strength and integrity deteriorate due to coating contamination
Solution Approach 1:
The patent removes the aluminum-based coating material layer from the edge regions of sheet metal pieces before welding. By extracting the harmful coating layer from the welding zone, the weld joint is prevented from contamination, thereby maintaining weld strength and integrity while the coating layers on the bulk surfaces continue to provide corrosion and scaling protection.
Solution Approach 2:
The patent applies different material properties to different regions of the sheet metal pieces. The edge regions where welding occurs have the coating material layer removed to ensure weld quality, while the remaining surfaces retain the coating layers for corrosion protection. This local differentiation resolves the contradiction between needing coating for protection and needing clean metal for strong welding.
2Strength
If additional material is added to the weld pool to enhance weld joint hardness and tensile strength, then weld joint strength is improved, but manufacturing complexity increases
Solution Approach 1:
The patent introduces an intermediary substance (additional material with specific composition) into the weld pool to modify the weld joint properties. This intermediary material, when added in controlled amounts, enhances the hardness and tensile strength of the weld joint without requiring complex manufacturing equipment, as it can be supplied through simple feeding mechanisms during the welding process.
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 prevents contamination of the weld joint by coating materials, thereby maintaining or improving the strength and durability of the weld, and can result in a weld joint with higher hardness and tensile strength than the base metal pieces.
Implementation Method 1
solidifying the weld pool to form a weld joint that joins the first and second sheet metal pieces together
Implementation Method 2
using a secondary heat source to heat a protective material comprising aluminum so that the protective material flows in the weld region
Implementation Method 3
providing additional material to the weld pool to influence a composition of a weld joint that is formed when the weld pool solidifies
Implementation Method 4
when the welded blank assembly is subsequently heated and quenched in a heat treating process, provides the heat treated weld joint with a hardness and/or a tensile strength
Data Source
AI summary
A welded blank assembly is formed by welding first and second sheet metal pieces together at a weld joint. At least one of the sheet metal pieces includes a boron steel or press hardenable steel base material layer and an aluminum-based coating material layer, along with a weld notch where at least a portion of the coating material layer is removed before welding. An additional material can be provided during welding to influence weld joint composition and/or a secondary heat source can be used to heat and flow a protective material in a weld region of the blank assembly. The weld notch has a width that may be related to the width of a heat-affected zone formed during welding.