ARALDITE® CY 5948-1 / ARADUR® HY 925-1

• To facilitate stirring and handling, Araldite® CY 5948-1 Resin should be preheated to 55 - 60°C and Aradur® HY 925-1 WMO Hardener or Aradur® HY 925-1 CH Hardener should be preheated to 30 - 40 °C in their original containers.
• After a thorough mixing, the resin should be maintained at 50 - 60°C in the production equipment under a 1 - 5 mbar vacuum while the hardener should be maintained at 30 - 40 °C under a 1 - 5 mbar vacuum. The vapor pressure of the individual components should be taken in to account. As the hardener component has a higher vapor pressure, it should preferably be processed under a higher vacuum and a lower temperature than the resin component.
• Long pot life is desirable in the processing of any Araldite® casting resin system. Proper mixing will result in better flow properties and reduced tendency to shrinkage, lower internal stresses and therefore cured parts with improved mechanical properties and improved partial discharge behaviour in high voltage applications.
• For Araldite® CY 5948-1 Resin and Aradur® HY 925-1 WMO Hardener (Standard system): At about 50°C to 55°C, with the appropriate ratio, mix Araldite® CY 5948-1 Resin with Aradur® HY 925-1 WMO Hardener and silica flour together very thoroughly under vacuum between 0.5 - 5 mbar. The effective pot-life of the mix is about 1 day at max.25 °C.
• For Araldite® CY 5948-1 Resin and Aradur® HY 925-1 CH Hardener (Fast system): At about 23°C to 25°C, with the appropriate ratio, mix Araldite® CY 5948-1 Resin with Aradur® HY 925-1 CH Hardener and silica flour together very thoroughly under vacuum between 0.5 - 5 mbar. The effective pot-life of the mix is about 2 days at max.25°C.
• The use of a thin film degassing mixers is recommended for medium to high viscous casting resin systems or for mixing at lower temperatures. This type of equipment can typically cause a 10 to 15°C rise in temperature due to friction. Depending on quantity, mixer type, mixing temperature and application, the mixing time is typically about 0.5 - 3 hours under a 0.5 to 8 mbar vacuum.
• The effective pot-life of the mix is about 1 day at temperatures of 25°C or lower. Conventional batch mixers should be cleaned once a week or at the end of the shift. For longer work interruptions, the pipes of the mixing and metering equipment should be cooled and cleaned with the resin to prevent sedimentation and/or undesired viscosity increase. Interruptions over a week-end (approx. 48h) without cleaning may be possible as long as the lines are cooled at temperatures of 18°C or lower.

Molding temperature Conventional vacuum casting: 80 - 100°C

Demolding times (depending on mold temperature and casting volume) Conventional vacuum casting: 8 - 20 hours

Cure conditions (minimum post cure) in conventional vacuum casting:

• Araldite® CY 5948-1 Resin with Aradur® HY 925-1 WMO Hardener and silica flour: 6 hours to 8 hours at 80°C +3 hours at 90°C + 2 hours at 100°C + 4 hours at 110°C 8 hours at 120°C
• Araldite® CY 5948-1 Resin with Aradur® HY 925-1 CH Hardener and silica flour: 12 hours at 80°C + 3 hours at 90°C +3 hours at 100°C +4 hours at 110°C +8 hours at 120°C

To determine whether cross-linking has been carried to completion and the final properties are optimal, it is necessary to carry out some relevant measurements on the actual part or to measure the glass transition temperature of the cured system. Different gel and cure cycles in the manufacturing process are likely to lead to a different degree of crosslinking, hence different glass transition temperatures.

Araldite® CY 5948-1 Resin contains some curing catalyst and / or accelerator. It should preferably not be stored for long periods at temperatures exceeding 40°C nor should it be exposed to temperatures more than 100°C for more than 2 hours. Incorrect handling will result in an increase in viscosity and reduced performance properties of the cured system.

Araldite® CY 5948-1 Resin should be stored in a dry place, in their sealed original container, at temperatures between 2°C and 40°C (35.6°F and 104°F). Under these storage conditions the shelf life is 3 years (from date of manufacture). These products should not be exposed to direct sunlight.

Aradur® HY 925-1 WMO Hardener and Aradur® HY 925-1 CH Hardener contain some curing catalysts and / or accelerators. Storage at elevated processing temperatures (>40°C) for extended periods (e.g. >5 days) will result in an undesirable increase in viscosity and will negatively affect the reactivity of the mixed system. This hardener is sensitive to moisture. Partially used containers should be closed immediately after use. Nitrogen blanketing is highly recommended as well as the use of a desiccant venting device unless the material is going to be used rapidly after opening.

Aradur® HY 925-1 WMO Hardener and Aradur® HY 925-1 CH Hardener should be stored in a dry place, in their sealed original container, at temperatures between 2°C and 40°C (35.6°F and 104°F). Under these storage conditions the shelf life is 6 years (from date of manufacture). These products should not be exposed to direct sunlight.