Have you adjusted your flow rate? Slicers are usually pretty close to spot on for 0.4mm nozzles but in my experience going up or down in nozzle size usually results in having to change the flow % pretty significantly. In addition to what others have said about minimum layer time / heating the parts up too much, I think you may be over-extruding as well.

The test I like for testing flow is to print a handful of cubes ~15 layers tall, with 2 bottom layers, 3 infill layers, and 10 top layers. Print each one at a different flow rate (in cura you can change settings per part to print them all at once) and look at the top layer when it’s done. You don’t want any bulging from between print lines (over-extruding) or any gaps in between them (under-extruding).