for Structurally Bonding Composites
DAAT® Technology Designed to Overcome Challenges of The Structural Bonding of Composites within the Automotive Industry
The European Environment Agency has set out EU environmental policy targets and objectives to be achieved by 2050 in a move towards a green economy in Europe. Part of this regulation involves mandatory emission reductions. Regulation 443/2009/EC (EU, 2009f) sets a 130 g CO₂/km limit for new passenger cars by 2015 (with the target phased in from 2012) and a 95 g CO₂/km limit by 2020.
To achieve the new emission targets, the automotive industry will begin to create new light weight vehicles, focusing attention multi-material platforms. In many areas simply replacing black metal parts and body panels with carbon fibre reinforced plastic (CFRP) is the first step to light weighting. This solution helps with the initial problem of reducing carbon emissions through weight reduction, however with the introduction of CFRP comes a multitude of challenges, not least is how to create an efficient method for structurally bonding CFRP panels in a high volume environment.
The current CFRP panel manufacturing process involves a 6 axis robotic system applying a liquid epoxy and polyurethane (PU) adhesives to the panel followed by clamping the bonded panels with jig fixtures, or adding rivets. Due to the low green strength of the adhesive the procedure of adding temporary mechanical fixings to hold the panels together is necessary to ensure accurate alignment during cure time.
The parts are transported through to either a storage area while the adhesive cures or cycled through an additional heat source to accelerate the cure time.
The jigging and fixtures add a high cost to the infrastructure required to manufacture CFRP parts. Other areas of critical control include the need to closely control the thickness of the bond-line across the whole panel to maximise adhesive performance. Controlling this to between 0.2mm – 0.3mm can be very challenging across parts with complex geometry and has to be mechanically controlled using stand-offs and complex jigging arrangements. Costs can be prohibitive and scalable only with very high infrastructure costs and a large carbon footprint.
DAAT® Dual Action Adhesive Tape
As part of a drive to create the most advanced bonding systems, Tecman Speciality Materials Ltd is currently investing in developing DAAT® Dual Action Adhesive Tape. The importance of this ground breaking development has been recognised by Innovate UK Technology Strategy Board who are part funding the development project with a SMART Grant.
With the potential to transform the way that carbon fibre reinforced plastic (CFRP) panels are manufactured, DAAT® combines the instant adhesion benefits of pressure sensitive adhesive (PSA) tape, with the bond performance of a structural epoxy and the impact resistance of structural polyurethane adhesive. This patented composite adhesive has high impact reinforcement through the bond line adding to its structural performance.
By replacing the current bonding method with DAAT® Dual Action Adhesive Tape technology, the manufacturing process is simplified and accelerated due to the instant adhesion properties. DAAT® effectively eliminates the need for utilising complex, heavy jigs or mechanical fastenings such as self piercing rivets. The bond-line is finely controlled to give a perfectly consistent adhesive layer and includes a reinforcement fibre layer to increase the impact resistance properties.
Features and Benefits of DAAT® Dual Action Adhesive
|DAAT Features||DAAT Benefits|
|Simplified Application||No issues with open time or controlling adhesive slump. Product can be applied to substrate by hand on low – medium volume applications.|
|Instant Adhesion||High green strength provides instant adhesion.|
|Application at different stage||DAAT can be applied off line or at a Tier 1 and then be transported to the next assembly point at the OEM, at another location or even held in storage awaiting the next assembly step.|
|Rapid Processing||Quick to apply using robotic applicators. Provides instant adhesion between surfaces|
|Low Cost Curing||Low cure temperature with rapid cure times|
|High Green Strength||High green strength allows parts to be bonded with sufficient adhesion strength to enable them to support their own weight. This allows the manufacturing process to continue without the requirement for jigging and clamping during initial cure|
|Improved Impact Resistance||Inclusion of reinforcement fibres provides superior tensile impact resistance|
|Multi Substrate Bonding||DAAT has the ability to instantly bond multiple substrates such as carbon fibre and aluminium|
For further information about Tecman’s ground breaking DAAT® technology contact us.