| 摘要 |
A method of manufacturing a metallurgically monolithic integral heated probe for injection molding. An electrical terminal and three portions of the probe body are made and assembled together with an electrical heating element extending in an aligned bore. The forward portion is made of abrasion resistant high speed steel, while the rest of the probe body is made of hot work tool steel. A removable and reusable filler tube is screwed into a threaded seat in the rear cap portion and a quantity of silver is loaded into it. After a nickel alloy brazing material is applied to the joins, the assembly is heated in a reduced oxygen atmosphere in a vacuum furnace according to a predetermined cycle. The nickel alloy seals all the joins and the silver braze fills all the spaces between the components to provide a metallurgically monolithic integral probe. Using silver which is more conductive and has a lower melting temperature than copper reduces the cycle time and avoids having to heat the assembly into the austenitizing range of the steel body.
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