| 摘要 |
A method of casting comprising placing in a mould an elongate rigid member (10; 10 min ; 10 sec ) surrounded or coated along at least part of its length, with an insulating material (13; 13a; 13b); introducing into the mould molten metal; the molten metal directly contacting the insulating material (13; 13a; 13b), permitting the metal to set to form a coating and to decompose completely the insulating material; removing the casting from the mould and removing the elongate rigid member (10; 10 min ; 10 sec ) from the casting; the elongate rigid member (10; 10 min ; 10 sec ) is formed with an opening (12; 12 min ; 12 sec ), to facilitate the passage of gases produced during said decomposition of the insulating material (13; 13a; 13b) from the mould. |
