A STUDY ON EXTRUSION OF HEAVY ALLOY POWDER

With continual extension of application fields of heavy alloys, the forming processes for bars and tubes with small sizes and large L/D ratio by conventional die pressing or isostatic pressing have certAlN limitations. It is of practical importance to investigate and adopt new powder extrusion process.
This paper deals mAlNly with new extrusion technology for heavy tengsten alloy. By using wax as plasticizer, the author studied the influence of extrusion process parameters on extrusion density under different addition of wax as well as the influence of various factors on dewaxing process under the condition of dewax in hydrogen atmosphere. Extruded compacts with various diameters(φ613mm) were obtAlNed. Heavy alloy with superior structures and properties was obtAlNed by sintering in hydrogen. The new extruding process has following features—simple equipment,high production efficiency, and accurate size and good surface finish of bars. It provides a way of high productivity and reliability for manufacturing medium and small size bars and irregular shape parts and will be of benefit to increasing the application range of heavy alloy.