EPOCAST® 1645 FR A/B

EPOCAST® 1645 A/B is a two-component, ultra-low-density, flame-retardant epoxy void filler designed for edge filling/reinforcing of honeycomb structures used in aerospace interior applications. Both Epocast® 1645 FR A and B are non-sticky, very soft pastes which can be easily mixed and applied manually and are water-cleanable after application. EPOCAST® 1645 A/B sets quickly at room temperature and is sandable shortly after application. It is well-suited for aerospace applications requiring low density, high strength, and rapid component assembly.
  • TypeDocument Name
View All Documents

Enhanced TDS

Identification & Functionality

Chemical Family
RTU Product Type

Features & Benefits

Labeling Claims
Ready-to-Use Product Features
Product Feature
  •  Sandable in as little as 70 minutes
  •  Service strength in 24 hours
  • Color mix indicator
  •  1:1 mix ratio by weight or volume
  • Off-ratio tolerant by up to 40%
  • Retains strength at high temperatures
  • Flame retardant: meets FAR 25.853a requirements
  •  Meets BMS 5-28 Type 9 requirements
  •  Ultra-low density
  •  High strength and high modulus
  •  Service temperature up to 350°F
  •  1 year shelf life
  •  1-to-1 mix ratio by weight and volume
  •  Excellent tolerance with off ratio
  •  Easy to process with color mix indicator and rapid sanding
  •  “Wet-Finger” smoothable (with Glove)
  •  No SVHC as defined by REACH*
Product Features
  • Flame retardant: meets FAR 25.853a requirements
  •  Meets BMS 5-28 Type 9 requirements
  •  Ultra-low density
  •  High strength and high modulus
  •  Service temperature up to 350°F
  •  1 year shelf life
  •  1-to-1 mix ratio by weight and volume
  •  Excellent tolerance with off ratio
  •  Easy to process with color mix indicator and rapid sanding
  •  “Wet-Finger” smoothable (with Glove)
  •  No SVHC as defined by REACH*
Product Advantages
  • Weight savings
  • Faster processing
  • Easy to use
  • Versatile applications
  • Reduced inventory costs
Features and Benefits
  • Flame retardant: meets FAR 25.853a requirements
  • Meets BMS 5-28 Type 9 requirements
  • Ultra-low density
  • High strength and high modulus
  • Service temperature up to 350°F
  • 1 year shelf life
  • 1-to-1 mix ratio by weight and volume
  • Excellent tolerance with off ratio
  • Easy to process with color mix indicator and rapid sanding
  • “Wet-Finger” smoothable (with Glove)
  • No SVHC as defined by REACH (Does not intentionally contain any Substances of Very High Concern (SVHC) for authorization as published by the European Chemicals Agency (ECHA) pursuant to Article 59 REACH as of December, 2013)
  • EPOCAST® 1645 A/B void filler can increase productivity thanks to its 1:1 mix ratio, color mix indicator, and excellent off-ratio mixing tolerance. It is also sandable within 2-3 hours and cures in one day at room temperature. A long shelf-life helps to simplify inventory management and further reduce costs. This flame-retardant void filler can also increase end-product performance. Compared to competitive products, EPOCAST® 1645 A/B void filler can provide up to a 23% improvement in strength at room temperature and up to an 85% improvement at elevated temperatures.

Applications & Uses

Application Area
Cure Method
Markets
Applications
Mixing Ratio

Product

Parts by weight or volume

Epocast® 1645 FR A Resin

100

Epocast® 1645 FR B Hardener

100

Material temperatures should be above 18°C (65°F) when mixing. Mix both components thoroughly for several minutes to insure complete and uniform mixing.

Properties

Physical Form

Regulatory & Compliance

OEM Specifications
Quality Standards

Technical Details & Test Data

Gel Time
1645 FR A Resin 1645 FR B Hardener Gel Time at 23°C, min

Peak Exotherm Temperature, °F (°C)

5 g 5 g 185 Not measured
10 g 10 g 150 Not measured
25 g 25 g 85 Not measured
50 g 50 g 65 121 (49)
100 g 100 g 45 130 (54)
200 g 200 g 40 160 (71)
55 g 50 g (10% off ratio) 85 Not measured
60 g 50 g (20% off ratio) 90 Not measured
65 g 50 g (30% off ratio) 95 Not measured
70 g 50 g (40% off ratio) 95 Not measured
50 g 55 g (10% off ratio) 75 Not measured
50 g 60 g (20% off ratio) 80 Not measured
50 g 65 g (30% off ratio) 80 Not measured
50 g 70 g (40% off ratio) 80 Not measured

Gel time and work life varies greatly with the mass of the material being mixed at one time. Too large a quantity of mixed material will reduce the work life/gel time and produce a significant and undesirable heat release unless it is spread rapidly.

Sandability

EPOCAST® 1645 A/B provides an excellent sandability once hardened. The minimum cure time prior to sanding will depend on the mass of EPOCAST® 1645 A/B being used and on the actual ambient temperature. The table below provides some general guidelines for various mass of EPOCAST® 1645 A/B cured at 73°F (23°C). At elevated temperature (e.g. with hot air) the minimum sandable time can be significantly reduced in order to save processing time.

Epocast® 1645 A/B

Sandable time

10 g 4 - 5 hours
30 g 3 - 4 hours
50 g 2 - 2.5 hours
100 g 70 - 80 minutes
Processing Condition

Processing Data

 

Typical cure cycles

1 - 3 days at 23°C

Gel at RT + 1 - 3 hours at 52°C

Gel Time*:

1645 FR A Resin 1645 FR B Hardener Gel Time at 23°C, min Peak Exotherm Temperature, °F (°C)
5 g 5 g 185 Not measured
10 g 10 g 150 Not measured
25 g 25 85 Not measured
50 g 50 g 65 121 (49)
100 g 100 g 45 130 (54)
200 g 200 g 40 160 (71)
55 g 50 g (10% off ratio) 85 Not measured
60 g 50 g (20% off ratio) 90 Not measured
65 g 50 g (30% off ratio) 95 Not measured
70 g 50 g (40% off ratio) 95 Not measured
50 g 55 g (10% off ratio) 75 Not measured
50 g 60 g (20% off ratio) 80 Not measured
50 g 65 g (30% off ratio) 80 Not measured
50 g 70 g (40% off ratio) 80 Not measured

*Gel time and work life varies greatly with the mass of the material being mixed at one time. Too large a quantity of mixed material will reduce the work life/gel time and produce a significant and undesirable heat release unless it is spread rapidly.

Sandability: Epocast® 1645 FR A/B provides an excellent sandability once hardened. The minimum cure time prior to sanding will depend on the mass of Epocast® 1645 FR A/B being used and on the actual ambient temperature. The table below provides some general guidelines for various mass of Epocast® 1645 FR A/B cured at 73°F (23°C). At elevated temperature (e.g. with hot air) the minimum sandable time can be significantly reduced in order to save processing time.

Epocast® 1645 FR A/B Sandable time
10 g 4 - 5 hours
30 g 3 - 4 hours
50 g 2 - 2.5 hours
100 g 70 - 80 minutes

 

Processing Guidelines
Property Value Unit Condition
Gel time 65 min at 25°C, 100 g
Typical cure cycles 1 - 3 days

1 - 3 days at 23°C or Gel at RT + 1 - 3 hours at 52°C

Typical Physical Properties

General performance at 23°C (cured 3 hours at 125°F/52°C) 

Property Test Method Value
Compressive Strength, psi ASTM D695 2,850
Compressive modulus, ksi ASTM D695 190
Lap shear strength, Al-Al, psi ASTM D1002 1,100
Shore D Hardness ASTM D2240 58
Glass Transition temperature, °C ASTM E1824 50
CTE, μm/m∙°C ASTM E831 41.5
Flammability (12-second vertical burn) (Extinguishing time, sec) FAR 25.853a max. 2
Extinguishing time, sec (Burn length, in) FAR 25.853a max. 2

Packaging & Availability

Packaging Type
Regional Availability
  • Americas
  • EIMEA
Packaging Information

Available in bulk packaging

Storage & Handling

Storage Conditions
  • Epocast® 1645 FR A/B epoxy syntactic adhesive should be stored in a dry place in the original sealed containers at temperatures between 2°C and 40°C (36°F and 104°F).  After use, tightly reseal containers.
  • The product should not be exposed to direct sunlight.

Other

Physical Properties
ValueUnitsTest Method / Conditions
Density0.45-0.48 g/cm³g/cm³ASTM D792 at 25°C