We were gifted a set of Cuisanart stainless steel (impact bonded) pots and pans last Winter and use them fairly heavily for cooking at home.
We just started to notice however that a few of the smaller pieces are pinging/popping/knocking when they get put on the burner. The noises return when we cool the piece down, and occasionally if you tap it on the counter. From my experience designing and fabricating parts it seems like the different metals in the bonded billet are separating from the pan in some fashion and the noises are a result of that happening.
Fortunately they're under warranty, and Cuisanart has already put new ones in the mail saying we can toss the old ones if we want. However, I'm wondering whether they would be safe to keep and use instead, if it's just sounds.