3M Structural Adhesives™

SA9820 (Orange) and SA9820 (Black)

2K structural adhesive formulated forincreased design flexibility and lightweighting.

Better science for better
adhesion from 3M.
Since 1925 when one of our lab assistants invented masking tape,
3M has been applying science to life – developing adhesive products
and technologies that help entire industries and individual businesses
worldwide. The work that began with a single 3M engineer now spans
decades and generations – and all of it goes into each of our products
developed for automotive OEMs, like 3M™ Structural Adhesive 9820.

3M™ Structural Adhesives SA9820 and SA9820B
SA9820 and SA9820B are highly toughened
two-part epoxy adhesives formulated
for increased design flexibility in OEM
automotive applications. The adhesives allow
for bonded substructures to be stored for up
to two months before full E-coat/paint cycle
curing. They are excellent for bonding carbon
composites and multi-material structures
as they also cure at low temperature.

SA9820B offers the same technicalperformance as the standard orange
version, yet the black colour of the adhesive
will guarantee a better visual appearanceon CFRP substrates, with no visual defectsof the bond line.

Productfeatures

Performance advantages

Customer benefits

EpoxychemistryŔ High bond strength with cohesive failure modeon aluminium substrates as well as compositematerials

Ŕ Robust, structural
bonding performanceŔ Compatible with wet and dry lubesŔ Excellent long-term durability (to heat, humidity,salt water)
Two-partŔ Extended shelf-lifeŔ Controlled reactivity; balance of longer open
time and proper lock-up e.g. after induction

Ŕ Provides good bondstrength under various
process conditions

Ŕ Broad handling anddispensing windows

Ŕ Room temperature strength build-up
Ŕ Can be dispensed with commercially available
dispensing systems; off-ratio toleranceŔ Wash out resistance in E-Coat
FlexiblecuringŔ Low temperature activation 80°C to 115°C
depending on cycle timeŔ Reduced potential for panel distortion andincreased options for multi-material bondingŔ Induction cured in seconds

Ŕ Broad curing windows;
faster cycle times

Physical properties

Part APart B

Mixed
adhesiveColour
SA9820
SA9820B

RedRedYellowBlackOrangeBlack% solids

100%

100%

100%

Density (±0.06)

1.07g/cc

1.07g/cc

Viscosity at RT [Pas] (±20)

70260Multi material bonding

CFRP to aluminium

A two-part structural adhesive for greater design flexibility
3M™ Structural Adhesives SA9820 and SA9820B have a wide process
window and can be applied under normal body-in-white (BIW) conditions
at OEMs or in Tier-1 companies for modular assemblies and later fitting in BIW.
The adhesives afford the bond strength of a one-part adhesive andexceeds the strength, stiffness and crash performance of premium
two‑part structural adhesives.

CFRP to CFRP

It can be induction cured at room temperature for fast geometric joint lockup. It can also be cured conventionally at bake temperatures as low as 80°C.
The adhesive features controlled reactivity for a longer work time (approx.
1 hour) and proper panel lock-up after induction heating for accelerated curing.

Aluminium to magnesiumFatigue testing
Overlap shear test joints (etched 2024T3 aluminium) were fatigued using
a 1kN cyclic load. The samples were exposed to 50°C/95% RH during thewhole of the test.
Fatigue testing in hot/wet conditions is a key discriminator of both adhesive
and mechanical performance.
The test was conducted to 10 million cycles and then stopped. All the test
joints survived the 10 million cycles and were then tested to destruction.
Fatigue cycles(test stopped)

Substrate

Adhesive

Shear stressMPa (testedafter fatigue)

Failuremode

10,202,766
fatigue cycles
50°C/95% RH

2024T3

SA982027.21

Cohesion

10,202,775
fatigue cycles
50°C/95% RH

CFRP

SA9820B

26.93

Cohesion

If you would like to speak to a 3M expert, please getin touch on 0330 053 8940.

Magnesium

Aluminium

Automotive and Aerospace Solutions Division
3M United Kingdom PLC
3M Centre
Cain Road, Bracknell
Berkshire RG12 8HT
Tel: 0870 6080 060
www.3M.co.uk/automotive

3M Ireland Limited
The Iveagh Building
Carrickmines Park
Carrickmines
Dublin 18

Please recycle. Printed in the UK. © 3M 2020.
3M is a trademark of 3M Company. All rights
reserved. OMG120613

CFRP