Abstract
Hydrostatic pressing method is radically different from ordinary mechanical ones, having high pressure resisting chamber in which green compact setin rubber die or rubber envelope can be pressed by Pascalian hydraulic force. This report is related to study green strength of TiC-Co system cermet powder compacted by hydrostatic pressing device, specially constructed to be able to endure until under hydraulic pressure of 10, 000kg/cm2, and here concerns especially with transverse strength of green compact, previously pressed slightly in metal or plastic die and finally compacted strongly in rubber envelope.
As a factorial design, L81 340 type orthogonal design was used, adopting 5 factors as following…… A: Co powder content (0, 20, 40%), B: paraffin percentage (1, 2, 3%), C: time effect between the intervals of addition of paraffin and preliminary pressing (2, 24, 48hr.), D : preliminary pressing force (100, 200, 300kg/cm2) and F: hydrostatic pressing pressure (1, 2, 3ton/cm2). In addition, as auxiliary experiments, two designs of more increased levels among A, B and F were tested to get more precise imformation. Transverse strength as characteristic value was measured by the specially ordered testing apparatus having very high sensive mechanism to small amount of load and reveals that the main effects of A, B, C and F are significant, and interactions AXB, AXF are also significant. Each linear and cubic effect of A, B and F are significant, while each quadric effect is non-significant except A.
