Fraunhofer Institute for Machine Tools and Forming Technology
Fraunhofer Institute for Machine Tools and Forming Technology

Mechanical joining

Innovative processes for lightweight construction and composite design

Innovative joining processes are the basis for implementing sustainable component concepts. We develop processes, e.g. for joining of high-strength steels with light alloys based on aluminum, magnesium or titanium, and for joining of material combinations of metals and fiber-reinforced plastics. Another research focus lies on optimization of joining processes regarding quality, reproducibility as well as energy- and resource-efficiency. This includes the description of the entire production process for car body assembly groups using continuous experimental and numerical investigation of the process chain (forming, joining and lacquer drying).

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Clinching and riveting processes

  • Clinching with flat counter tool
  • Clinching of magnesium materials
  • Clinching of thick sheet metal
  • Hem flange bonding
  • High speed joining
  • Patchwork technology
  • Solid self-piercing riveting with divided die

Process combinations

  • Electromagnetic joining
  • Hybrid joining
  • Hydro-joining
  • Integration of piezo-actuators

Measuring and testing methods

  • Impulse-thermography
  • Measurement technology

  • Cost-effective joining of same and different materials
  • Lightweight and composite construction: exploiting energy-efficient alternatives to resistance spot-welding and other thermal joining processes
  • Overcoming process limits and combining advantages by using hybrid joining processes (clinching, self-pierce riveting, adhesive bonding, hem flange bonding)
  • Specific optimization of process variables by simulation

Process development

  • Market analysis
  • Investigation of process chain
  • Process optimization, sensitivity analyse, process reliability
  • Cost-benefit calculation
  • New and further development of joining processes:
  • Mechanical joining processes, especially for multi-material design
  • Hybrid joining processes with adhesive bonding
  • Planning and technological dimensioning of processes, tool and machine
  • Recommendations for investments regarding machines or technologies
  • Joining in press plants
  • Experimental and numerical simulation of process chains in joining
  • Tolerance analysis in process chains

Development and evaluation of mechanical joining strategies

  • Market analysis
  • Feasibility studies
  • Technology development
  • Development of process parameters and ideal forming strategies
  • Benchmarking
  • Numerical simulation, numerical simulation of structure
  • Manufacturing of prototypes
  • Analysis of joint formations (FE calculation and experiment)
  • Determination of the component behavior in thermal processes
  • Design of joints

Quality assurance

  • Process monitoring (pre-/in/post-process)
  • Inspection of assembly groups (quasi-static, cyclic and crash)
  • Testing the properties of joints and components
  • Development of testing methods
  • Climate test and corrosion tests

Joining machines

  • Eckold MFG 005 (self-pierce riveting and clinching machine)
  • Eckold c-bracket-column machine DFG 500/10
  • Friedrich 35KN wobble press
  • Friedrich B3013 radial-point riveting system
  • Hilti test station
  • Kerb-Konus solid self-pierce riveting machine
  • Impulse riveting machine
  • Promess 320
  • Promess 350/180
  • Promess UFM 100/70/200Tox-Pressotechnik (solid riveting machine)
  • WEBER wobble-riveting system NEB 5510
  • DUNKES servo spindle press
  • Adhesive technology (SCA Schucker, Netzsch, Beyer&Otto)

Industrial robots

  • ABB IRB 660
  • KUKA KR 15
  • KUKA KR 150 R 2700 extra
  • KUKA VW Hemming robot

Inspection technology

  • DynaMess table-top testing machine
  • GOM (ARAMIS, PONTOS, ARGUS,
  •  TRITOP, ATOS)
  • Drop test stand Instron dynatup 8160
  • Drop test stand Instron dynatup 9250HV
  • Feutron double climatic chamber
  • (2-chamber process for differential climatic strain)
  • Hegewald & Peschke 50kN
  • Universal inspection machine
  • Hydropuls test stand INSTRON-IST
  • Koehler corrosion test chamberHK400
  •  (Salt spray test and condensation change test)
  • MAXIMATOR hydraulic unit
  • Universal inspection machine Inspekt desk 50
  • VÖTSCH heating and drying cabinet
  • VTU 150/150/20-200 °C

Sample preparation / metallography

  • Struers CitoPress-1
  • Struers Discotom-5
  • Struers Discotom-60
  • Struers ProntoPress-10
  • Struers TegraPol-11
  • Struers Tegramin-25

Software

  • ABAQUS
  • ANSYS
  • Autocad
  • CAD, CATIA
  • CREO / ProEngineer
  • DEFORM
  • Exceed / 3D_CSS
  • Fame tools
  • Fortran Compiler
  • Hypermesh
  • LSDYNA
  • Matlab, MathCad, Mathematika
  • National Instruments
  • OptiSLang
  • Origin
  • PAM-STAMP
  • Rapidform XOR
  • SolidWorks