Let me talk briefly first. Generally, metal mobile phone cases are also die-cast and stamped, such as magnesium alloy and titanium alloy, which are mainly produced by die-casting, such as stainless steel and aluminum alloy.
Under normal circumstances, the draft angle must be made, otherwise it will not be drawn.
Post-processing flow, that's a lot. The most common are baking paint, electroplating, vacuum electroplating and anode pad printing.
The production technology of plastic mobile phone case: injection molding, processing technology is basically these, of course, there are other hot melt, ultrasonic and so on.