I have a 2014 charger prusuit 5.7

I have had constant coolant issues that started with 2 water pumps being replaced and then I also had a oil pressure sensor go out went out so I had that replaced as well. I was having issues with the radiator so I had a brand new one installed. The car was running great. A week later the one of the dual fan blades broke completely and punctured the the new radiator. I thought maybe because it was a old fan it had just been worn down and maybe broke. I installed a second radiator (3rd total) and anoter fan that came attached with the radiator. The car was running great again.. 3 days later the fan breaks while sitting at idle after parking. I had the air conditioner running at the time. The car wasn't over heating I had the cars temperature gage on at all times. Does anyone know what would cause a fan to keep breaking? It's not loose and theres nothing in the way to hit the blades, it has plenty of space between the radiator it should never hit anything.

 

Maybe a flaw in the blades themselves, though, if it were, you would think we would hear about it more.... And this is the first time I have heard about this.... Look at the breaks themselves, is it a uniform color all the way thru? Or is it darker/lighter in places??