| 摘要 |
The object of the invention is a method of consolidation of powder materials by means of a device provided with a gastight operating chamber (1), a press connected (11) to a first electrode (3) and to a second electrode (6), wherein between the electrodes there is located in a die (4) the consolidated powder (5), wherein the press (11) exerts pressure on the consolidated powder with the first electrode (3) and the second electrode (6). To the first electrode (3) and the second electrode (6) there is connected a circuit comprising a power supply unit (9) so that the flow of current provided by the power supply unit (9) is closed through the first electrode (3) and the second electrode (6), and the consolidated powder (5). Simultaneously, the consolidated powder (5) is subjected to pressure and stimulated by current pulses. The voltage applied to the powder (5) in pulse peak fits within the range of 50 V to 900 V, and pulse duration is shorter than 300 ]is. The consolidation of powder (5) is performed in at least two steps. In the first step a pressure of the press (11) corresponding to pressure on the powder (5) within the range of 2 MPa to 15 MPa is applied, while the values of pulse current, pulse duty cycle and repetition frequency are chosen such that the temperature of the powder was constantly in the range of 0.05 do 0.3 of melting temperature of the powder. In the second step a pressure of the press (11) corresponding to pressure on the powder (5) within the range of 15 MPa to 200 MPa is applied, while the values of pulse current, pulse duty cycle and repetition frequency are chosen such that the temperature of the powder (5) was constantly in the range of 0.6 to 0.9 of melting temperature of the powder (5). Furthermore, the object of the invention is a device for consolidation of powder materials, provided with a gastight operating chamber (1), a press (11) connected to a first electrode (3) and to a second electrode (6), wherein between the electrodes there is located in a die (4) the consolidated powder (5), wherein the press (11) exerts pressure on the consolidated powder with the first electrode (3) and the second electrode (6), wherein to the first electrode (3) and the second electrode (6) there is connected a circuit comprising a power supply unit (9) and switching means so that the flow of current provided by the power supply unit (9) is closed through the first electrode (3) and the second electrode (6), the consolidated powder (5) and the switching means. Furthermore, the device is provided with a vacuum pump and means for measuring the temperature (8) of the consolidated powder. Furthermore, the voltage of the power supply unit (9) is within the range of 50 V to 900 V, and the switching means are configured to close the current flow path for a time shorter than 300 μs. A substance according to the invention is a result of consolidation of the substance comprising at least one of the group including A1203, SiC, Si3N4, WC, Ta, ReB2, Zr02, TiC, TiN using the method according to the invention. |
