PMID- 30836706
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20201001
IS  - 1996-1944 (Print)
IS  - 1996-1944 (Electronic)
IS  - 1996-1944 (Linking)
VI  - 12
IP  - 5
DP  - 2019 Mar 4
TI  - The Influence of Clamping Pressure on Joint Formation and Mechanical Performance 
      of Ti6Al4V/CF-PEEK Friction-Riveted Joints.
LID - 10.3390/ma12050745 [doi]
LID - 745
AB  - This work aims at investigating the influence of pre-set clamping pressure on the 
      joint formation and mechanical strength of overlapping direct-friction-riveted 
      joints. A pneumatic fixture device was developed for this work, with clamping 
      pressure varying from 0.2 MPa to 0.6 MPa. A case study on overlapping joints 
      using Ti6Al4V rivets and woven carbon fiber-reinforced polyether-ether-ketone 
      (CF-PEEK) parts were produced. Digital image correlation and microscopy revealed 
      the expected compressive behavior of the clamping system and the continuous 
      pressure release upon the joining process owing to the rivet plastic deformation 
      and the polymer squeezing flow. Two preferential paths of material flow were 
      identified through the alternate replacement of the upper and lower composite 
      parts by a poly-methyl-methacrylate (PMMA) plate-the composite upward and 
      squeezing flow between the parts which induced their separation. The ultimate lap 
      shear forces up to 6580 +/- 383 N were achieved for the direct-friction-riveted 
      CF-PEEK overlap joints. The formation of a gap to accommodate squeezed polymer 
      between the composite parts during the process had no influence on the joint 
      mechanical performance. The increase in the clamping pressure for joints produced 
      with a low friction force did not affect the joint-anchoring efficiency and 
      consequently the joint strength. On the other hand, the combined effect of a 
      high-friction force and clamping pressure induced the inverted bell shape of the 
      plastically deformed rivet tip, a lower anchoring efficiency, and the 
      delamination of the composite, all of which decrease the mechanical strength by 
      31%. Therefore, the higher the friction force and clamping pressure, the more 
      defects would be generated in the composite parts and the more changes in the 
      shape of the plastically deformed rivet tip, leading to a lower level of 
      quasi-static mechanical performance. All the joints failed by initial bearing of 
      the composite and final rivet pull-out. The findings of this work can contribute 
      to further improvement of the clamping design for industrial application.
FAU - Borba, Natascha Z
AU  - Borba NZ
AD  - Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, 
      Institute of Materials Research, Materials Mechanics, Solid State Joining 
      Processes, 21502 Geesthacht, Germany. natascha.zocoller@hzg.de.
AD  - Hamburg University of Technology, Institute of Polymer and Composites, 21073 
      Hamburg, Germany. natascha.zocoller@hzg.de.
FAU - Dos Santos, Jorge F
AU  - Dos Santos JF
AD  - Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, 
      Institute of Materials Research, Materials Mechanics, Solid State Joining 
      Processes, 21502 Geesthacht, Germany. jorge.dos.santos@hzg.de.
FAU - Amancio-Filho, Sergio T
AU  - Amancio-Filho ST
AD  - Graz University of Technology-TU Graz, Institute of Materials Science, Joining 
      and Forming, BMVIT Endowed Professorship for Aviation, Kopernikusgasse 24/1, 8010 
      Graz, Austria. sergio.amancio@tugraz.at.
LA  - eng
GR  - 304169/2014-5/Conselho Nacional de Desenvolvimento Cientifico e Tecnologico/
GR  - Austrian aviation program TAKE OFF/Bundesministerium fur Verkehr, Innovation und 
      Technologie/
PT  - Journal Article
DEP - 20190304
PL  - Switzerland
TA  - Materials (Basel)
JT  - Materials (Basel, Switzerland)
JID - 101555929
PMC - PMC6427510
OTO - NOTNLM
OT  - Friction Riveting
OT  - clamping influence
OT  - joint formation
OT  - mechanical properties
COIS- The authors declare no conflict of interest.
EDAT- 2019/03/07 06:00
MHDA- 2019/03/07 06:01
PMCR- 2019/03/04
CRDT- 2019/03/07 06:00
PHST- 2019/02/18 00:00 [received]
PHST- 2019/02/27 00:00 [revised]
PHST- 2019/02/28 00:00 [accepted]
PHST- 2019/03/07 06:00 [entrez]
PHST- 2019/03/07 06:00 [pubmed]
PHST- 2019/03/07 06:01 [medline]
PHST- 2019/03/04 00:00 [pmc-release]
AID - ma12050745 [pii]
AID - materials-12-00745 [pii]
AID - 10.3390/ma12050745 [doi]
PST - epublish
SO  - Materials (Basel). 2019 Mar 4;12(5):745. doi: 10.3390/ma12050745.