Welding and Joining Institute (ISF) at JEC WORLD Paris, March , 2018

Transcription

1 Welding and Joining Institute (ISF) at JEC WORLD 2018 Paris, March , 2018

2 Working Fields and Competences in Adhesive Bonding Selection and evaluation of the appropriate adhesive and bonding process Design and construction of adhesively bonded joints Characterization and evaluation of performance (ageing) Surface pre-treatment before bonding, with special focus on laser radiation and atmospheric pressure plasma Hybrid joints of fibre-reinforced plastics and pin structured metals Repair concepts for vehicles made of fibre-reinforced plastics Structural Health Monitoring systems for adhesively bonded joints Thermal direct joining with induction and conductive resistance heating 2

3 Surface Pretreatment Atmospheric pressure plasma (with process gas, if applicable) Low pressure plasma (with process gas, if applicable) Laser pre-treatment in association with partner companies: CO2 ( nm; TEA und CW) Nd:YAG (1064, 532, 355, 266 nm; UKP) Blasting machines Ultrasonic cleaning Wet-chemical methods Other methods, e.g. Pyrosil, SACO, flaming ika RWTH, SLCR ika RWTH, SLCR CO 2 -Laser pre-treatment of FRP components Atmospheric pressure plasma 3

4 CFRP laboratory for adhesive surface pretreatment of CFRP components Equipment High speed CFRP cutting machine with suitable saw blade Manual grinding machine with different grain sizes CNC 3-axis milling machine with milling cutters optimized for CFRP for surface contouring Suitable CFRP vacuum cleaner for CFRP particle The number and size of particle exposure is continuously monitored and documented by an optical particle counter 4

5 Testing Equipment at ISF Processing of adhesive 1-K/2-K dosing equipment Heating press (12 to, 300 C) Mechanical testing equipment Static/dynamic Tension/compression, (temperature control possible -130 C up to 540 C) Biaxial testing: tension/compression + torsion (static/cyclic) Permanent load stand (temperature control and moist climate) F F peeling F cleaving 5

6 Characterization of Adhesive and Surface Tensiometer determination of surface tension (Wilhelmy method, Washburn method powder) Contact angle measurement determination of wetting behavior of surfaces (determination surface energy, polar/dispersible portions) Differential Scanning Calorimetry (DSC) determination of thermo-physical adhesive properties (melting point determination, cross-linking properties of polymers, determination of heat capacity, crystallization, etc.) Microscopy incl. analytics (SEM + EDX) Material-, fracture pattern analysis (morphology, element distribution, adhesion / cohesion portions), DSC Cross-linking 6

7 Measurement and testing technology Aging Tests Test climate according to standard or requirement Climate chambers Salt-spray chambers UV-chambers Natural weathering Laboratory furnace Image: Different weather conditions 7

8 BMBF- Research Project ProPhoMuLA Process-oriented process development of photonic tools for bonding multimaterial lightweight structures in automobiles Initial situation Lightweight constructions made of FRP and metal Adhesive bonding is the most important joining technology for multi-material compounds Surface pretreatments for FRP have high process complexity Not suitable for high-volume applications Research objective Laser as surface pre-treatment tool for FRP Development of a robust adhesive bonding process chain Taking into account the constraints of the automobile manufacturing holistically Adhesive dosing unit Induction Heating 3D Measurementsystem Robot Control Laser System Robot The authors thank the Federal Ministry of Education and Research (BMBF) for funding the program "Photonic methods and tools for resource-efficient, lightweight design" to the sub-project "Exploration of an automated overall process" (FKZ: 13N12771). In addition, the authors would like to thank all involved project partners. 8

9 AIF-Research Project ProKleb - Process monitoring and control for surface preparation of PUR- and thermoplastic FRP with laser Initial situation Adhesive bonding is the most important joining technology for multi-material compounds Surface pre-treatment especially for PUR- and TP-FRP necessary for excellent and durable bond quality No process monitoring and control of laser surface pre-treatment for FRP available Research objective Development of a controlled laser pretreatment process with spectrometry and pyrometry as monitoring tools Detection of ablation products by means of spectrometry Indirect control of the process via a temperature-based process window Achieving short process times and high reproducibility for pre-treatment of FRP, even for complex 3D geometries Optical detection of surface contours coarse contaminants Variable parameters: power, line spacing, scanning speed, etc. Component with any contour Feed direction Laser system for processing the surface Positioncontrol: variable z- axis z Inline process monitoring by surface analysis 9

10 AIF-Research Project ProKleb - Process monitoring and control for surface preparation of PUR- and thermoplastic FRP with laser Laser pre-treatment of FRP part with contaminations Results of inline process monitoring High parameter without contaminations Lower parameter with contaminations 10

11 AIF-Research Project Key technologies for SMEs - Interactive workshop of the future for electric vehicles in FRP Initial situation Need for FRP in automotive industry to reduce the weight Previous repair of FRP: generous exchange of components High cost and environmentally questionable Objective Cost- and resource-efficient repair of FRP components Innovative production- and joining processes under consideration of vehicle workshop-conditions [Auto Zeitung] [Auto Zeitung] Damage assessment & evaluation Simulative design & illustration of the damaged area Methods for economic repair: Manufacturing & joining process for repair patches Competences of bonding technology: Structure machining processes (e.g. milling, grinding) scarf Surface preparation methods Joining processes to bond the repair patch The IGF-projects N, N and 26LN of the research association "Vereinigung zur Förderung des Institutes für Kunststoffverarbeitung in Industrie und Handwerk an der RWTH Aachen e.v. is funded through AiF within the framework of the industrial collective research programme (IGF) by the Federal Ministry for Economic Affairs and Energy on the basis of a decision by the German Bundestag. 11

12 AIF-Research Project GlasKleben Exemplary building for the application of structural glazing (left) and schematic representation of a structural glazing construction (right) The IGF-project N/2 of the research association DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.v." is funded within the framework of the industrial collective research programme (IGF) by the Federal Ministry for Economic Affairs and Energy on the basis of a decision by the German Bundestag. 12

13 Tension σ AIF-Research Project GlasKleben Initial situation Load-bearing metal-glass/glass-glass bonding (structural glazing) in construction requires an approval in individual cases (German: ZiE) or general building inspection approval Mullins-Effect at cycled load d C No consistent methodology for the interpretation and reliable simulation of these bonds available B c c d Research objective Derivation of a consistent interpretation method of adhesive bonds in construction Consideration of model- and mechanical stress-dependent material parameters taking into account the damage (Mullinseffect) A b b Elongation ε Loading course 1. Loading and unloading 2. Loading and unloading 3. Loading and unloading The IGF-project N/2 of the research association DECHEMA Gesellschaft für Chemische Technik und Biotechnologie e.v." is funded within the framework of the industrial collective research programme (IGF) by the Federal Ministry for Economic Affairs and Energy on the basis of a decision by the German Bundestag. 13

14 AIF-Research Project SmartSHM Efficient Health Monitoring of Structural Adhesive Bonds Cross section of a rotor blade with adhesive bonds as a demonstrator Source: Henkel AG & Co. KGaA Schematic view of adhesive bond Image correlation of adhesive bond 14

15 AIF-Research Project SmartSHM Efficient Health Monitoring of Structural Adhesive Bonds Initial situation Damage inside the component/adhesive Direct inspection difficult Damage evaluation problematic Tolerances in production quality Influence of environmental and aging processes Manufacturing Defects SmartSHM Small (Defect) Undamaged Structure Research objective Nonlinear structural analysis Rating of hotspots How are damages evaluated? Identification of sensitive structural damage indicators Optimization of sensor positions Direct damage evaluation based on the damage indicator Big (Damage) Damage progress Calculation Undamaged Structure Change in Structural Behavior Calculation Damaged Structure Damaged Structure Damage Evaluation Optimal damage Indicator Residual Strength Remaining Lifetime Countermeasures Sensor Network Intrinsic Damage Evaluation 15

16 Thermal direct joining of metals and (fiber-reinforced) plastics Process flow: Local resistance heating of metal Conductive heating and melting of the plastic at the contact surfaces Wetting of the metal through plastic melt Key Parameter: Material combination and surface pretreatment Joining temperature Joining pressure Process time Pneumatic cylinders Connections for power supply Steel PA 6 Sample Advantages: No need for an additional adhesive Process times < 15 sec High bond strengths up to 25 MPa Ringelectrode Spotelectrode Counter holder (cooled) 16

17 Equipment for thermal direct joining Principle induction technique Principle resistance heating Metal p Plastic i p Metal Q Induction coil Plastic Electrodes Experimental set-up induction technique Experimental set-up resistance heating Displacement sensor Pressing tool Elektrodes Metal Sample holder Plastic 17

18 Advanced joining technologies for hybrid composites of FRP and metal AIF-Research Project SMMJ Smart Multi Material Joint AIF-Research Project Welding-Island 18

19 AIF-Research Project SMMJ Smart Multi Material Joint Process Generating small-scale metallic interlocking elements by a modified CMT process Intrinsic joining process of FRP on textured steel surface Matrix polymer is used as an adhesive Fibers "wrap around" Pins (FRP still malleable) Advantages Fibers of FRP remain undamaged Power flow remains undisturbed Force is transferred into deeper layers of the laminate Form-fitting elements allow ductile failure behavior Joint can be monitored by an integrated sensor system Hybrid composite of concrete and metal Different pin geometries Hybrid composite of CFRP and metal Picture: opportunities by the use of CMT-Pins The IGF-project N/2 of the research association "Forschungskuratorium Textil e.v." and Forschungsvereinigung Stahlanwendung e.v. is funded within the framework of the industrial collective research programme (IGF) by the Federal Ministry for Economic Affairs and Energy on the basis of a decision by the German Bundestag. 19

20 AiF-Research Project Welding-Island Initial situation Ultra fast joining techniques for hybrid material joints of FRP and metal that do not damage the textile structure and enable a ductile post-failure behavior Research objective Small-scale pins moldable in CMT-Process (Cold- Metal-Transfer) can be integrated into a FRP to enable multi-projection welding processes Small-scale pins do not require fiber damage. Ultra fast multi-projection welding processes do not harm matrix material Metals: titanium, aluminum, steel Quasi-homogeneous force transmission into deeper fiber layers Ductile post-failure behavior (fail-safe backup) enables residual load capacity for countermeasures Patent pending (DE ) 20

21 Basic Seminar Adhesive Bonding at ISF RWTH Aachen Booking details English course: September 12th, 2018 German course: September 13th, 2018 Course fee: Event location: Binding application: 580 (incl. snacks & beverages) Aachen, Germany Content-related questions: +49 (0)241/

22 Your contact: Mr. Josef Weiland Adhesive Bonding Technology Phone: +49 (0)241/ Thank you for your attention! ISF - Welding and Joining Institute RWTH Aachen University Pontstraße Aachen Germany Tel.: +49 (0) Fax: +49 (0) office@isf.rwth-aachen.de