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

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Next Generation of Structural Body Shop Adhesives

• Dr. Andreas Lutz, IABC, Frankfort, 13.-14.06.2017

Safety Increased energy management capability Acoustic Comfort Increased dynamic stiffness: 2-3Hz Environment Weight reduction

• High strength steel usage
• Panel thickness reduction
• Multi material design

Durability & Driving Comfort Increased static stiffness to 20% Savings Cost down capabilities

• Weld spot reduction up to 50%
• Metal content reduction up to 10kg/vehicle
• Process speed improvement of between 50&100%

Structural Adhesives Benefits

Self initiative: applied for vehicle performance improvement Driven by governmental regulations

Performance Drivers – Structural Adhesives

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 CO2 Emissions for vehicle fleet

• Continuing specifications under elaboration
• Regulations differ significantly in dependence of the region

Europa

2015 130g CO2/km 2020 95g CO2/km

USA CAFE

Coperate Average Fuel Economy 2016 160g CO2/km 2025 101g CO2/km

Japan

2016 139g CO2/km

China

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

Pure Steel Design Optimised Steel Design Aluminum intense Design CFK intense Design

100% 20% 40% 60% Schematic and idealised

Präsentiert durch AUDI, Bad Nauheim

Lightweighting Potential

The car body contributes ~35-40% of vehicle’s entire mass mass The vehicle mass contributes ~25% of fuel consumption

Forecasted Material Usage – McKinsey 29 % 67 % Light ht Weight ght Materials rials

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 BETAMATETM Structural EP High Elastic BETAFORCETM Structural PU A High Modulus toughened Adhesives B Low Modulus toughened & thermal strain resistant Adhesives A High & lower modulus high elastic Adhesives B Tailored curing speeds to adjust to the final application

Structural Adhesive Continuum of Performance

800 400 100 50 35 30 25 20 15 10 5 1 Elongation % Lap Shear Strength (Mpa)

Structural Epoxy Adhesives: Elastic PU Adhesives & Sealants: Semi-Structural PU Adhesives: Elastic PU Sealants: Structural PU Adhesives: Epoxy Adhesives: Epoxy Hybrid Adhesives: Selection Considerations

• Assembly

requirements

• Substrates bonded
• Substrate coatings
• Cure profile
• Functional

performance

• Body or Trim shop
• Manufacturing

process

Structural Epoxy Technology Structural PU Technology

Body Shop Paint Trim Shop Repair

80-160° C, 30’ 180° C, 30’ 25° C

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

BETAMATETM Crash Durable Structural Adhesives

• Toughening Technology

Solution: Multifunctional toughening polymers are developed for phase separation during adhesive cure

• ffering

superior crack resistance under loading, thus guaranteeing the mechanical integrity of the joint. Challenge: How to modify an epoxy structural adhesive to be crash durable?

5 μm

Second-Phase Toughening

Uncured adhesive epoxy matrix toughener dissolved in Heat Cure Change in solubility parameter Phase separation epoxy matrix toughener particles dispersed in Cured adhesive Effect on toughening

• Particle size
• Amount of toughener
• Continuous epoxy phase
• Interface of toughener particel with matrix

Toughening mechanisms

• Shear band formation
• crack path deflection
• crazing / microcracking
• crack pinning / broadening
• cavitation

BETAMATETM 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 result in improved:

• Oil absorption
• Tack to surfaces

Improved tackiness of adhesive formulations improves wash-off resistance New technology

Good and poor wash

• ff performance after

rotating in a bath at 60°C and 140 rpm Lab validation test to judge tack performance Good and poor wash

• ff performance after

water beam jet spray at 60°C, 1 bar

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

BETAMATETM Body Structure Adhesives for robust applications in automotive manufacturing

BETAMATETM Body Structure Adhesives improved performance for bonding advanced high strength steel (AHSS)

5 μm

Particles can phase-separate, preventing crack propagation

20 40 60 23 °C

• 40 °C
• 60 °C
• 70 °C

Impact Peel Strength [N/mm]

Maintains ductility, even at low temperature

New toughener development optimizes phase separation during adhesive cure and offer:

• Increased adhesive modulus
• High fracture toughness & increased modulus

Mild steel left and higher strength steel right colomn

BETAMATETM Body Structure Adhesives improved performance for bonding AHSS

BETAMATETM structural adhesives generational development Significant increase in fatigue durability & failure mode at same static strength

BETAMATETM Body Structure Adhesives for Aluminum Bonding

10 20 30 40 50 60 10 20 30 40 cylces passed stress durability impact peel strength [N/mm]

New adhesive formulations

• ffer

constant bulk properties under environmental ageing. As a result, mechanical values like tensile strength remain on a high value during environmental exposure.

BETAMATETM Body Structure Adhesives improved corrosion performance for steel bonding

DX 56 Z 100 DX 56 ZM 90

DX 56 Z 100 DX 56 ZM 90

20 5 10 15

Lap shear strength [MPa] Excellent adhesion on zinc and zinc-magnesium coated steel grades before and after corrosion

BETAMATETM Body Structure Repair Adhesives

T-peel results on left aluminum and right on hot diped zinc coated steel

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

• 60
• 40
• 20

High modulus stability with temperature

BETAMATETM Body Structure Adhesives for Multi Material Mix Bonding

27.1 25.3 21 24 24.1

Lap shear strength [MPa]

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

thick steel substrate thick steel substrate spacer debonding/loss of surface cohesion

Very good failure mode after passing e-coat oven

Examples Grad A Grad B Grad C

E-Modulus [MPa], ca.

800 400 150

Elongation [%], ca.

20 28 40

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