Description:
Project ID: D2018-49
Background
Several approaches have been taken to join aluminum plates or sheets. However, each has disadvantages. For example, resistance spot welding of common alloys can cause expulsion, distortion, short electrode life, and the formation of voids and cracks. Friction stir welding is limited in that it requires equipment to securely hold sheets, leaves an exit hole, and cannot be used for thin sheets or curved joints. Self-piercing riveting requires an extremely high riveting force and die alignment, and cannot join brittle metals. Given the limitations of current solutions, there is still a need for a more efficient way to join aluminum plates.
Invention Description
Dr. Zhang, Professor from the Department of Mechanical, Industrial and Manufacturing Engineering has developed a set of four connectors with unique features that provide a more efficient way to join aluminum plates or sheets.
1. Self-driven screw which has two ends with opposing thread directions.
Application: Connecting two thick plates
Advantage: Does not require a screw driver and are resistant to loosening.
2. Arrays of punched protrusions
3. Arrays of forged semispherical-head protrusions
4. Forged arrow-head protrusions
Application:
• Connecting two sheets/plates
• Sheet metal industry; automotive, household appliances, etc.
Advantage:
• Strong mechanical interlocking
• Lower stress concentration results in strengthened joints.
• Protrusions can be placed on either or both sides
• They can be used for a variety shapes, including curvature at joints
• No complex fixtures, tool alignment or a die
• Tunable shape, size, and arrangement to meet joining needs.
IP Status: US Patent Pending, No. 2020/0072264