Instrument panel forming method, instrument panel, and instrument panel forming apparatus

An instrument panel forming method for forming an instrument panel having a base material part made of a base material, and a different material part that is disposed in a state of being surrounded by the base material part and is made of a different material different from the base material, the method comprising:

• a first supply step of closing a frame-shaped core at a position of a cavity that is a boundary between the base material part and the different material part of the instrument panel after forming, setting the cavity to a state of being separated into a base material part-forming section and a different material part-forming section, and supplying the base material serving as the base material part and the different material serving as the different material part to the cavity;
• and
• a second supply step of opening the frame-shaped core with a pressure applied to the different material kept greater than a pressure applied to the base material, bringing the base material and the different material into contact with each other, and causing the different material to protrude into the base material and to be joined to the base material, in a central part of a boundary between the base material and the different material in a thickness direction of the base material and the different material in which solidification of the base material and the different material is delayed.