Bonding Film

AF 131-2

- 3 -

Suggested

Preparation

Procedure

(continued)

III. Cure Cycle

A. General

The tack, flow and cure initiation temperature for 3M™ Scotch-Weld™ Bonding

Film AF 131-2 is a time-temperature relationship and depends upon the rate of

heat input.

Normally, Scotch-Weld AF 131-2 will have the following properties:

Tack Temperature

120-180°F (49-82°C)

Flow Temperature

180-300°F (82-149°C)

Cure Initiation Temperature

300-350°F (149-177°C)

A minimum cure temperature of 350°F (177°C) is recommended to effect a cure

in a reasonable length of time. (Approximately 60 minutes). A cure of 90 minutes

at 350°F (177°C) and 50 psi pressure is suggested where maximum results are

desired.

B. Cure Cycle (Autoclave or Platen Press)

The following cure cycle is recommended to obtain dense glue lines which give

the strengths reported in the Product Performance section.

Cure Cycle

1. Bonding Pressure: Apply before reaching a

50 psi

bond line temperature of 150°F (66°C) and

maintain throughout press cure cycle.

2. Bond line temperature rise rate.

3°F/minute

3. Cure.

90 min. @ 350°F (177°C)

4. Temperature at which pressure is released.

200°F (93°C) or below

3-7°F / Min. Rise Rate

Test

Test Temperature

Cure Cycle Average

Overlap Shear (PSI)

-67°F (-55°C)

2000 psi

RT

2300 psi

350°F (177°C)

3000 psi

Note: The following technical information and data should be considered representative or

typical only and should not be used for specification purposes.

The following product performance data has been obtained in the 3M Laboratory under the

conditions specified. General application methods and bonding procedure are described

later. All data reported in this section was developed under a cure cycle using 50 psi

bonding pressure applied by a platen press, a 3°F/minute bond time temperature rise from

80°F to 350°F (27°C to 177°C) with 90 minutes at 350°F (177°C).

I. Aluminum to Aluminum Overlap Bonds

The following data shows typical values obtained with Scotch-Weld AF 131-2 on

aluminum overlap panels. Overlap bonds consist of 1/2" overlap unprimed 0.063"

2024T-3 bare aluminum 4" x 7" panels, with one layer of Scotch-Weld AF 131-2 film

adhesive. Tests were conducted per MMM-A-132 methods.

Product

Performance