Wessex System 310: Adhesive strength
Specifications: handling characteristics
(mPas @ 25°C)
|S.G.||Flash Point (°C)|
(1:1 by weight)
Specifications: mix properties
|Wessex 310 epoxide resin||Part A||100 parts by weight|
|Wessex 310 epoxide hardener||Part B||100 parts by weight|
|100g Gel Time @ 25°C||285 mins|
|Thin Film Gel @ 25°C||720 mins|
Specifications: working properties
|Mass (kg)||Working Time (Mins @ 25°C)||Gelation Time (Mins @ 25°C)|
The effect of temperature and mass on the working and gelation time of WRA 310 Epoxy System
|Temperature||Working time||Gelation time||Cure time of thin film 1mm thick (hours)|
|°C||Thin film 1mm thick||1.4kg mass||6.0kg mass||Thin film 1mm thick||1.4kg mass||6.0kg mass||Thin film 1mm thick|
Adhesive strength on steel
After seven days' cure, the bond strength of the epoxy mix between circular mild steel plates is greater than 4.38 MPa – the minimum requirements to meet specification. Typical strength values when tested to failure are approximately 10.0 MPa.
Adhesive strength on aluminium
Tests on extruded aluminium which was degreased, then abraded and degreased again before coating with Wessex 310 produced an average adhesive strength of 7.55 MPa (six specimens tested after seven days) and, importantly, the coefficient of variation was low. The failure mode was primarily cohesive (approximately 70%) within the adhesive layer.
The coverage rate of the Wessex 310 epoxy for these tests on aluminium was about 0.7 kg/m² spread, i.e. the adhesive thickness was approximately 0.5mm.
Adhesive strength on WBP plywood
Tests to determine the bond strength of the epoxy on timber after seven days' cure produced an average adhesive strength of 3.79 MPa with a low coefficient of variation illustrating the excellent reproducibility of the bond. The mode of failure, which was almost 90% cohesive within the wooden substrate, is of significant importance.
Tiles based on Vamac to London Underground Specifications
After seven days' cure at room temperature, the average bond strength of Wessex 310 epoxy on this tile substrate is 3.97 MPa and, again, the failure mode was cohesive (approximately 85%) within the Vamac compound. The coefficient of variation was extremely low.
Please note: the work detailed above was carried out with glue lines nominally 0.5mm thick, but in practice, because of undulating surfaces, glues lines of greater thickness may well be necessary.