Next Generation of Structural Body Shop Adhesives Dr. Andreas Lutz, - PowerPoint PPT Presentation

Next Generation of Structural Body Shop Adhesives Dr. Andreas Lutz, IABC, Frankfort, 13.-14.06.2017 Dow.com

Performance Drivers – Structural Adhesives Self initiative: applied for vehicle performance improvement Durability & Increased static stiffness to 20% Driving Comfort Acoustic Increased dynamic stiffness: 2-3Hz Comfort Structural Adhesives Increased energy management capability Safety Benefits Weight reduction • High strength steel usage Environment • Panel thickness reduction • Multi material design Cost down capabilities • Weld spot reduction up to 50% Savings • Metal content reduction up to 10kg/vehicle • Process speed improvement of between 50&100 % Driven by governmental regulations

P E R F O R M A N C E M A T E R I A L S D I V I S I O N Automotive Manufacturing

Governmental Regulations drive Vehicle Lightweight Design Targeted CO 2 Emissions for vehicle fleet  Continuing specifications under elaboration  Regulations differ significantly in dependence of the region Japan USA CAFE Europa Coperate Average Fuel Economy 2016 139g CO 2 /km 2015 130g CO 2 /km 2016 160g CO 2 /km China 2020 95g CO 2 /km 2025 101g CO 2 /km 2020 5l/100km

Lightweight Potential  Ca. 35-40% contribution of car body on entire vehicle mass  Ca. 25% contribution of vehicle mass to fuel consumption 100% Pure Steel Design Optimised Steel Design 20% 40% Aluminum intense Design Präsentiert durch AUDI, Bad Nauheim CFK intense Design 60% Schematic and idealised

Lightweighting Potential The car body contributes ~35- 40% of vehicle’s entire mass mass The vehicle mass contributes ~25% of fuel consumption Light ht Weight ght Materials rials 29 % 67 % Forecasted Material Usage – McKinsey

Adhesive Technologies Support Lightweight Concepts  Toughened Epoxy based structural adhesives for body shop application  High elastic PU based structural adhesives for trim shop applications Toughened BETAMATE TM High Elastic BETAFORCE TM Structural EP Structural PU A High Modulus toughened A High & lower modulus high Adhesives elastic Adhesives B Low Modulus toughened & B Tailored curing speeds to thermal strain resistant adjust to the final Adhesives application

Structural Adhesive Continuum of Performance Body Shop 180 ° C, 30’ Paint 80-160 ° C, 30’ Trim Shop 25 ° C Repair Structural Epoxy Technology Structural PU Technology Elongation % Selection Elastic PU Sealants: Considerations • Assembly requirements • Substrates bonded Elastic PU Adhesives & Sealants: 800 • Substrate coatings • Cure profile • Functional Semi-Structural PU Adhesives: performance • Body or Trim shop • Manufacturing Structural PU Adhesives: process 400 Epoxy Hybrid Adhesives: 100 Epoxy Adhesives: 50 Structural Epoxy Adhesives: 5 35 30 25 20 15 10 1 Lap Shear Strength (Mpa)

BETAMATE TM Crash Durable Structural Adhesives - Toughening Technology P E R F O R M A N C E M A T E R I A L S D I V I S I O N Challenge: Solution: Multifunctional toughening polymers are How to modify an epoxy developed for phase separation during structural adhesive to be crash adhesive cure offering superior crack durable? resistance under loading, thus guaranteeing the mechanical integrity of the joint. 5 μ m

Second-Phase Toughening Uncured adhesive Cured adhesive Heat Cure Change in solubility parameter Phase separation toughener dissolved in toughener particles dispersed in epoxy matrix epoxy matrix Effect on toughening Toughening mechanisms  Particle size  Shear band formation  Amount of toughener  crack path deflection  Continuous epoxy phase  crazing / microcracking  Interface of toughener particel with matrix  crack pinning / broadening  cavitation

BETAMATE TM Body Structure Adhesives for robust applications in automotive manufacturing The increasing volume of structural adhesive per vehicle can lead to wash-off issues in body shop when passing the different baths. New component development Improved tackiness of adhesive result in improved: formulations improves wash-off - Oil absorption resistance - Tack to surfaces New technology Good and poor wash Good and poor wash off performance after off performance after rotating in a bath at water beam jet spray 60 ° C and 140 rpm at 60 ° C, 1 bar Lab validation test to judge tack performance

BETAMATE TM Body Structure Adhesives for robust applications in automotive manufacturing The global manufacturing and the shipment of closure panels and entire bodies requires adhesive which offer improved humidity resistance.  Improved adhesives use new components which improves open time storage  Innovative catalysis offers excellent bulk viscosity stability

BETAMATE TM Body Structure Adhesives improved performance for bonding advanced high strength steel (AHSS) New toughener development optimizes phase separation during adhesive cure and offer: - Increased adhesive modulus - High fracture toughness & increased modulus Particles can phase-separate, Maintains ductility, even at low temperature preventing crack propagation Strength [N/mm] 60 Impact Peel 40 20 0 5 μ m 23 °C - 40 °C - 60 °C - 70 °C Mild steel left and higher strength steel right colomn

BETAMATE TM Body Structure Adhesives improved performance for bonding AHSS BETAMATE TM structural adhesives generational development Significant increase in fatigue durability & failure mode at same static strength

BETAMATE TM Body Structure Adhesives for Aluminum Bonding New adhesive formulations offer constant bulk properties under environmental ageing. As a result, mechanical values like tensile strength remain on a high value during environmental exposure. 60 cylces passed stress durability 50 40 30 20 10 0 0 10 20 30 40 impact peel strength [N/mm]

BETAMATE TM Body Structure Adhesives improved corrosion performance for steel bonding Excellent adhesion on zinc and zinc-magnesium coated steel grades before and after corrosion 20 Lap shear strength [MPa] 15 DX 56 Z 100 10 5 DX 56 ZM 90 0 DX 56 Z 100 DX 56 ZM 90

BETAMATE TM Body Structure Repair Adhesives 2 K body repair technology which combines high modulus for high strength substrate repair and excellent failure modes, especially under static and dynamic peel loading. E-Modulus: 2100 MPa Tensile strength: 33 MPa High modulus stability with temperature T-peel results on left aluminum and right on hot diped zinc 1,00E+10 0,8 coated steel 0,7 1,00E+09 0,6 0,5 1,00E+08 G' and G'' [Pa] tan delta 0,4 G' Pa G" Pa 1,00E+07 tan_delta 0,3 0,2 1,00E+06 0,1 1,00E+05 0 -60 -40 -20 0 20 40 60 80 100 120 140 Temperature [°C]

BETAMATE TM Body Structure Adhesives for Multi Material Mix Bonding New Multi component toughening polymer technology offers  Good tolerance to thermal induced strain caused by different material CLTE  Good adhesion and corrosion resistance with lower adhesive modulus Examples Grad A Grad B Grad C E-Modulus [MPa], ca. 800 400 150 Elongation [%], ca. 20 28 40 thick steel substrate Lap shear strength [MPa] 27.1 25.3 24 24.1 21 debonding/loss of surface cohesion spacer thick steel substrate Very good failure mode after passing e-coat oven

SUMMARY and OUTLOOK  Specific adhesive technologies have been developed which improve application features like wash-off performance or humidity resistance  Specific adhesive technologies and components have been developed which improve the mechanical performance on high strength steel and high strength aluminum alloys  Body repair adhesives have been developed which offer higher modulus and glass transition temperature  Adhesive technologies have been developed and are in development which adhere well on MMM body design