Green compact which undergoes electrosintering

Abstract

Abstract PURPOSE: To eliminate the production of unsintered portions at end parts and improve sintering yield by reducing the sectional areas of the electrode contact portions at both ends of a molding at the time of sintering the high melting point metal molding such as of W, Mo and other through current supplying and self-heating. CONSTITUTION: Current is supplied to a green compact 1 of powder such as of W, Mo and other, whereby the green compact is sintered through self-heating. At this time, both end parts of the green compact 1 are pressure held by electrodes 3, 5 and holders 4, 6, whereby current is supplied. Here, current is difficult to flow at the portions near the end faces where the electrodes 3, 5 do not contact, thus there is no evolution of excess heat and elevation to high temperatures is obviated. Hence, the portions where sintering is not sufficiently accomplished occur and the yield of sintering becomes poor. In such a case, the sectional areas of both end parts are reduced by opening tapered holes 2, 2' at both end parts or further forming tapered faces 9. The reduction in the sectional areas results in increased current density, increased temperature and eliminated unsintered portions, thus the entire part of the green compact 1 may be used as a sintered body. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Yoshiya Takizawa

Bibliographic Details