I believe it’s called affrication – changing a stop to a fricative.
T can become “ch”, and d can become a “j” sound.
This can happen in some North American accents when you have a T or D followed by an r or a y sound.
Train might sound like Chrain*, Drain might sound like Jrain.
My favourite is “Tuesday”, where some people add a y before the “oo” sound, and it becomes “Chewsday”. Or “Chewsdi” if they shorten the “day” to “dee”.
The “y” before “oo” can also happen in words like news and tube, giving us a potential for “Chyoob” instead of “tube”.
I’ve found that t to ch before r is more common among Gen X and younger, and Boomers tend to only make the change before y. But Gen X and younger tend to not have the y in words like “tube”, so that comes up less often.
D to J before r seems to be pretty common in all ages.
Getting people to hear the difference can be hard, especially if they’re self conscious about it. If you can get someone to say “Dane” and “Drain” (without saying the words yourself), then you can probably hear the difference…as long as they don’t know that you’re listening for a dr => jr sound change. Most people, even those who make tr => chr and dr => jr naturally are still capable of producing pure “tr” and “dr” if they try.