摘要 |
In order to more effectively utilise seed crystals 35, 55 to achieve a single crystal grain orientation for a component without the problems of utilising a helix constriction previously necessary to avoid epitaxial grain competition and growth. The present invention creates a wax component pattern 30 . This pattern 30 comprises integral sections of wax for a mould component section and for a spacer section with the seed crystal 35 or holder for that crystal therebetween. This pattern 30 is then utilised in order to form a final refractory mould within which the component is formed. By appropriate choice of the spacer section 32 , an appropriate spacing between an upper surface of the seed 55 which will be the initial interface with molten castable material to form the component and a chiller surface through which heat is transferred can be determined in order to achieve successful transfer of the seed 55 orientation to the formed component.
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