TITLE:
Dimensioning of Punctiform Metal-Composite Joints: A Section-Force Related Failure Criterion
AUTHORS:
Holger Seidlitz, Lars Ulke-Winter, Colin Gerstenberger, Lothar Kroll
KEYWORDS:
Composites, Multi-Material-Design, Hybrid, Joining, Failure Criterion, FDJ Joint
JOURNAL NAME:
Open Journal of Composite Materials,
Vol.4 No.3,
July
15,
2014
ABSTRACT: Reliable line production
processes and simulation tools play a central role for the structural integration
of thermoplastic composites in advanced lightweight constructions. Provided
that material-adapted joining technologies are available, they can be applied
in heavy-duty multi-material designs (MMD). A load-adapted approach was
implemented into the new fully automatic and fault-tolerant thermo mechanical
flow drill joining (FDJ) concept. With this method it is possible to
manufacture reproducible high strength FRP/metal-joints within short cycle
times and without use of extra joining elements for the first time. The
analysis of FDJ joints requires a simplified model of the joint to enable
efficient numerical simulations. The present work introduces a strategy in
modeling a finite-element based analogous-approach for FDJ-joints with glass
fiber reinforced polypropylene and high-strength steel. Combined with a newly
developed section-force related failure criterion, it is possible to predict
the fundamental failure behavior in multi-axial stress states. The
functionality of the holistic approach is illustrated by a demonstrator that
represents a part of a car body-in-white structure. The comparison of simulated
and experimentally determined failure loads proves the applicability for
several combined load cases.