2022 Fiscal Year Research-status Report
Elucidation of interface bonding mechanism and novel-tool strengthening principle in friction assisted joining of Al alloy to CFRTP
| Project/Area Number |
22K14511
|
|---|
| Research Institution | Osaka University |
|---|
Principal Investigator |
GENG PEIHAO 大阪大学, 接合科学研究所, 助教 (40900064)
|
|---|
| Project Period (FY) |
2022-04-01 – 2024-03-31
|
| Keywords | Friction spot joining / Al/CFRP / Interface structure / Performance control / Novel tool |
|---|
| Outline of Annual Research Achievements |
Pinless friction spot joining (FSpJ) has proven to be a competitive friction-based joining technique for fabricating metal/carbon fiber-reinforced thermoplastics hybrid joints. The study in the past one year investigated the feasibility of tool modification to improve the property of the silane-coated 6061-T6 aluminum alloy (Al alloy) and carbon fiber-reinforced polyamide-6 (CF/PA6) FSpJ joint. The interfacial structure, bonding strength and fracture surface of the joints obtained by four tools, viz, old flat (OT), new flat (NT), concave-shaped (CT) and ring-shaped tools (RT) with different rotation speeds, were analyzed and compared. An experimentally validated three-dimensional finite element model was also built to help understand FSpJ process. From the combined evaluation of thermal process and mechanical characteristics, the CT tool was recommended for the FSpJ of Al and CF/PA6 because it offered more uniform temperature distribution and improved macro-mechanical interlocking at the interface with good wetting conditions, sufficient chemical reaction and effective joining area, and a lower tensile residual stress, in comparison with other tools, and hence showed the highest shear force.
|
| Current Status of Research Progress |
Current Status of Research Progress
2: Research has progressed on the whole more than it was originally planned.
Reason
We have performed the theroetical analysis and experimental validation for the improvement of friction assisted joined Al/CFRTP by using novel tool structures. We hope to go on optimizing the tool structure and size, to adapt more complex and pratical thin-plate structures composed of various metals and CFRTPs.
|
| Strategy for Future Research Activity |
We is planning to design the novel tool wish smaller size and simple shape features, which is important for its pratical application in automobile light-weight structures. Moreovre, further basic anaysis for the quantitative relationship between interfacial structure and properties as well as thermo-mechanical histories will be carried out.
|
| Causes of Carryover |
As April approached, we designed new fixtures for the experiments, which should be budgeted for the first fiscal year. However, due to the approach of the end of the fiscal year, the implementation of the budget could not be completed. Therefore, we hope continue use the remained budget from the A fiscal year to pay the fee.
|
