MCIMX6Q5EYM10AD chip substrate or “code” on substrate turn red

[mitchliu]

Is this usual or has big risk?  the vendor say that these chips buy from arrow or avnet. But it's so strange.

normal chips maybe like that:

[art]

This "colorization" of the part's substrate may occur due to improper storage conditions, e.g. storage under high moisture, that might affect the device functionality and/or long term reliability. So, you should take care of it and check your vendor more accurately.

Best Regards,
Artur