It is possible to permanently seal porosity within metal castings or other porous objects with either Thermal Cure T120 or Cold Cure C120 without the need of process impregnation plant. By far the simplest to use is Thermal Cure as it is single pack ready to use, whereas cold cure requires premixing. Which ever is chosen, both rely on clean dry porosity to induce capillary attraction.
Choosing when to impregnate is important. If the porosity is clearly available for sealing in the virgin state, this is by far the best time. Once porosity becomes contaminated (machining cutting fluids etc..) attention must be given to its removal. Simple application of compressed air direct to the porous area may be all that is necessary, alternatively is to place the component in an oven for 1 hour @130°C – or do both. Preparation is everything.
For Thermal Cure T120 it is best to preheat the component to 110°C and then apply the impregnant direct to the porous area.
For Cold Cure C120 this requires the pre mixing of two components having a limited port life of a matter of a few minutes. I most cases this is still sufficient time to carry our the impregnation. The porous component is required to be cold, not above 30°C.
Methodology. Both impregnants can be applied by spray, brush or by pipette (drip). A swab of cotton wool placed over the defect can enhance the sealing of more difficult porosity. For T120 only, quench dipping directly into the impregnant can be a consideration. Both impregnants may be pressurised. Surface contamination will evaporate.