Received: 25 August 2016 /Accepted: 6 June 2017 /Published online: 23 June 2017
International Institute of Welding 2017
Abstract Modern lightweight constructions are increasingly
based on the use of multi-material design such as fibre-
reinforced plastics (FRP) combined with metallic material.
The technology of screwing is rated, especially for applica-
tions where high-strength and permanent joints are required,
among the established joining methods. To achieve a high-
quality lightweight design, often, profile-intensive construc-
tions are used, with the effect of one-sided accessibility to the
joining area. Against this background, flow drill screwing
offers an innovative solution for car body construction as well
as the assembly for joining this combination of material.
Currently, flow drill screwing with a pilot hole in FRP mate-
rials is used in the assembly process. To use this technology
without a pilot hole and use it economically in the body frame-
work, the auxiliary joining elements have to be optimised.
This publication includes the latest research findings in the
context of the development and qualification of joining by
using flow drilling screws. It focuses on the specific adapta-
tion of the auxiliary joining element with regard to the
geometry, the material and the coating systems. With macro-
scopic and microscopic sections, as well as studies of strength,
ultrasound and corrosion, it is possible to assess the quality of
new and original FDS joints.
Keywords (IIW Thesaurus) Arnold
Flow drill screwing
Self-tapping screw FLS
The customers’ request for increased comfort and new assis-
tance systems led to an increase of the total vehicle weight. In
order to counteract the increasing weight of the vehicle and to
reduce consumption and CO2 emissions, EU Regulation No.
443/2009 was adopted with the aim of reducing the CO
emissions of new cars to an average of 95 g/km by 2020 .
For this reason, the automotive industry has a growing
interest in significantly lowering the fuel consumption of
new vehicles. In addition to the development of more efficient
drive systems, a significant CO
saving can be achieved by
reducing the vehicle weight [2, 3].
Due to the high proportion, lightweighting efforts primarily
focus on the vehicle body. In order to achieve the weight
reduction, new construction methods and shaping processes
as well as a stress-related material selection are used. The latter
causes an increasing mix of different materials, whereby light
metals such as aluminium and magnesium are used in addition
to high-strength steel materials. In recent years, the use of
fibre-reinforced plastic composites (FRP) has become more
important in the automotive industry such as the example of
BMW 7 Series, Model G11, G12 shows (Fig. 1a) for instance.
Recommended for publication by Select Committee AUTO - Automotive
and Road Transport
The IGF-project IGF-Nr.: 17595 N/1 (EFB Nr.: 01/112) of the
Europäischen Forschungsgesellschaft für Blechverarbeitung e. V. was
promoted through the AiF under the program for the promotion of joint
industrial research and development (IGF) by the Federal Ministry of
Economics and Energy due to a resolution of the German Bundestag.
* Philipp Nagel
Laboratory for Material and Joining Technology (LWF), University
of Paderborn, Pohlweg, 47-49 Paderborn, Germany
Weld World (2017) 61:1057–1067
Flow drill screwing of fibre-reinforced plastic-metal composites
without a pilot hole