Environmental effects
Hi Crab,
Firstly, the blades I have worked with were not in AUS but they were in a tropical island location, so your point is transferrable. The issue of bond degradation is related directly fly to hydration of oxides on the surface off metals, and the surface preparation processes used during manufacture. Ideally the preparation process will produce hydration resistance, but older processes only provide short term resistance, and the susceptible surfaces eventually hydrate and the bond dissociates, leading to disbanding. This process is more rapid in hot-wet environments where the surface is susceptible to degradation, but in reality the main issue is the ability of the production processes to prevent hydration. The reason I am not bashing Robinson is that there is no specific regulatory requirement for a manufacturer to demonstrate resistance to hydration.
If I could get photos of the failure surface, I could provide an assessment of the causes of bond failures.
Regards
Blakmax