ARALDITE® CY 5940 / ARADUR® HARDENER HY 5941 / Silica

• Good mechanical and electrical properties at high temperatures
• Excellent thermal shock resistance
• Excellent toughness with high glass transition temperature.

• Indoor electrical insulators for medium and high voltage equipment such as switches and electrical components.
• Encapsulation of large metal parts.
• Recommended for parts subject to long-term stress, operating temperature up to 85°C.

The effective pot life at max. 25°C is approximately 2 days. Conventional final mixing tanks should be cleaned once a week or at the end of the workday. If work interruptions are longer, pipes containing the mix and metering equipment must be cooled and cleaned with ARALDITE resin components to prevent sedimentation and/or undesirable viscosity increase. If the temperature of the pipes is cooled to below 18 degrees, weekend interruptions (approximately 48 hours) without cleaning are possible. For viscosity increase and gel time data at various temperatures, please refer to Figures: 4.1 and 4.4.

Mold temperature

APG process 130 - 160°C
Conventional vacuum casting 70 - 100°C

Demolding time (depending on mold temperature and casting volume)
APG process 10 - 40 min
Conventional vacuum casting 5 - 8h
 

Curing conditions
APG process (minimum curing time) 4h at 130°C or 3h at 140°C
Conventional vacuum casting 12h at 130°C or 8h at 140°C

To determine whether the cross-linking is complete and whether the final performance is optimal, it is necessary to conduct relevant tests on actual items or measure the glass transition temperature. Different gel and curing procedures during the manufacturing process can lead to different cross-linking degrees and glass transition temperatures.

Process viscosity

Figure 4.1: Viscosity increase at 40, 60, 70 and 80°C (measured with Rheomat 115) (shear rate: D = 10 s⁻¹)

Figure 4.2: Relationship between initial viscosity and temperature (measured with Rheomat 115, D = 10 s⁻¹)

Figure 4.4: Gel time as a function of temperature measured using the Gelnorm Instrument (DIN 16945/6.3.1)

Mechanical and physical properties

Figure 5.1: Shear modulus (G') and mechanical loss factor (tan δ) as a function of temperature ISO 6721/ DIN 53445 (Method C / measurement frequency 1 Hz)

Figure 5.2: Variation of linear expansion coefficient (α) with temperature (reference temperature: 23°C) (ISO11359-2)

Electrical Properties

Fig. 6.1: Variation of loss factor (tan δ) and dielectric constant (εr) with temperature (measurement frequency: 50 Hz / IEC 250 / DIN 53483)

Fig.6.2: Change of volume resistivity (ρ) with temperature (Measurement voltage: 1000 V / IEC93/DIN53482)

Figure 6.3: Breakdown strength as a function of temperature measured with embedded Rogowski electrode DIN/ VDE 0303/ part 2 A = continuous voltage rise test / B = 5-minute step voltage rise test

Figure 6.5: Electrical aging life curves at 20, 50, 85, 105 and 150°C Tests were performed with embedded ball electrodes

Figure 7.1: Weight loss (sample: 50x50x3 mm) (limit: 4.0%)

Figure 7.2: TI 150 / 174 (weight loss 1.2%) TI 186 / 210 (weight loss 4.0%)

Figure 7.3: Bending strength loss (limit: 50%) ISO 178

Figure 7.4: TI 199 / 240 (bending strength)

Figure 7.5: Strain versus temperature at 23, 50 and 85°C Tensile stress: 20 N/mm², ISO899/DIN53444

Figure 7.6: Tensile stress versus loading time

Figure 7.7: Creep diagram at 50°C Maximum tensile stress as a function of loading time

Figure 7.8: Creep diagram at 85°C Maximum tensile stress as a function of loading time

Figure 8.1: Cracking resistance / thermal shock test Test specimen pass rate as a function of temperature gradient Average failure temperature: - 15°C Embedded metal parts with 2 mm radius corners.

General instructions for preparing liquid resin systems.

• Long pot life is desirable in the processing of any casting resin system. Mix all of the components together very thoroughly at room temperature or slightly above and under vacuum. Intensive wetting of the filler is extremely important. Proper mixing will result in:

1. Better flow properties and reduced tendency to shrinkage
2. Lower internal stresses and therefore improved mechanical properties on object
3. Improved partial discharge behaviour in high voltage applications.

• For the mixing of medium to high viscous Araldite® casting resin systems and for mixing at lower temperatures, we recommend special thin film degassing mixers that may produce additional self-heating of 10-15K as a result of friction.
• For low viscous Araldite® casting resin systems, conventional anchor mixers are usually sufficient. In larger plants, two premixers are used to mix the individual components (Araldite® and Aradur®) with the respective quantities of fillers and additives under vacuum.
• Metering pumps then feed these premixes to the final mixer or a continuous mixer. The individual premixes can be stored at elevated temperature (about 60°C) for up to about 1 week, de-pending on formulation. Intermittent agitation during storage is advisable to prevent filler sedimentation.
• Mixing time can vary from 0.5 to 3 hours, depending on mixing temperature, quantity, mixing equipment and the particular application. The required vacuum is 0.5 to 8 mbar. Degassing time is recommended at least 1 hour. The vapour pressure of the individual components should be taken into account.

Mandatory and recommended industrial hygiene procedures should be followed whenever our products are being handled and processed.

• Contamination of the eyes by resin, hardener or casting mix should be treated immediately by flushing with clean, running water for 10 to 15 minutes. A doctor should then be consulted.
• Material smeared or splashed on the skin should be dabbed off, and the contaminated area then washed and treated with a cleansing cream (see above). A doctor should be consulted in the event of severe irritation or burns. Contaminated clothing should be changed immediately.
• Anyone taken ill after inhaling vapours should be moved out of doors immediately.