Friction Stir Spot Welding Sequence for Sealant-Free Joint Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing friction stir spot welding methods struggle to achieve favorable joint quality when joining sealant-applied workpieces, as the sealant tends to flow into the plastic flow portion, compromising the integrity of the joint.
Innovation Solution
A friction stir spot welding apparatus and method that utilize a rotary tool with a columnar pin member, cylindrical shoulder member, and clamp member, controlled by a controller to press and rotate the workpieces, effectively squeezing out the sealant and preventing it from mixing with the plastic flow, ensuring a stable and sealed joint.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If sealant is applied between workpieces for corrosion resistance, then corrosion protection is improved, but sealant flows into the plastic flow portion during welding, deteriorating joint quality
Solution Approach 1:
The clamp member is pressed against the workpieces before the pin and shoulder members engage, performing a preliminary action that prevents sealant from flowing into the joint area during subsequent welding operations. This preliminary pressing action creates a sealant-free zone that maintains joint quality while preserving corrosion protection benefits
2Manufacturing precision
If clamp member presses workpieces before pin and shoulder members, then sealant is suppressed from flowing into joint, but additional pressing step increases process complexity
Solution Approach 1:
The clamp member, pin member, and shoulder member are integrated into a single rotary tool assembly that can perform both the preliminary pressing action and the welding operation in a coordinated manner. This merging of functions into one tool reduces overall process complexity while maintaining the beneficial sequence of operations
3Manufacturing precision
If sealant is squeezed out from joined portions, then sealant is prevented from mixing with plastic flow, but additional pressing force required increases energy consumption
Solution Approach 1:
The clamp member performs a preliminary pressing action that squeezes out excess sealant before the main welding force is applied by the pin and shoulder members. This preliminary action reduces the energy required during the actual welding process by pre-positioning the workpieces and removing excess sealant that would otherwise require additional energy to manage
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 solution enables the realization of favorable joint quality by suppressing the sealant from flowing into the plastic flow portion, maintaining the sealant's integrity and ensuring a stable bond between the workpieces, even in severe environments.
Implementation Method 1
rotate a contacting part of the rotary tool, the contacting part contacting the workpieces, such that the workpieces are softened by frictional heat and stirred to be joined together
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A friction stir spot welding apparatus includes a pin member (11), a shoulder member (12), a rotation driver (57), a forward/backward movement driver (53), and a controller (51). The controller (51) controls the forward/backward movement driver (53), such that the pin member (11) and/or the shoulder member (12) press workpieces before a clamp member (13) presses the workpieces, and then controls the rotation driver (57) and the forward/backward movement driver (53), such that the pin member (11) and the shoulder member (12) stir the workpieces.