| Popis: |
In this work, a new method for producing metal and ceramic powders by plasma spraying of rod blanks is proposed. A distinctive feature of this method is the use of a direct-acting plasmatron, where a bar-stock acts as one of the electrodes, and the cooling of the molten particles occurs place with a water screen. The water screen is not only in the lower part of the installation, but also it flows evenly from the walls, which gives a more efficient cooling of all molten particles, forming a regular spherical shape, and plasma flow. Water constantly circulates in a closed circuit, the heat is removed in a heat exchanger. Studies of powders were performed on scanning electron microscope “VEGA 3 LMH” produced by the company TESCAN, the Czech Republic, with the help of x-ray energy dispersive microanalysis AZtecEnergy Advanced busatti detector X-max 20 Standart, production company Oхford Instruments. The microhardness of the particles was measured according to GOST R ISO 6507-1-2007 on a MicroMet 5104 microhardness meter, with a load of 100 gs. |
