After an adventure on the hills the last thing you need to worry about is how best to clean your beloved pots and pans. You can of course hand wash any pots and pans in the sink without a care in the world, but what if you have the luxury of a dishwasher?
Titanium - Fire away! Titanium cookware is absolutely fine in the dishwasher and will come out sparkling, except for the burnt on porridge from when you left the pan unattended to get your favourite spoon perhaps.
Aluminium - DO NOT put aluminium cookware in the dishwasher. It will do terrible things and make your pots unusable! Always clean aluminium cookware by hand.