Technology

PLASMA TECHNOLOGIES

Using vacuum as a technological environment is extremely effective and profitable in the field of thermal and thermo-chemical processes and in the deposition of coatings.

Plasma is an ionized gas that consists of ions, electrons, radicals and neutral atoms and molecules, the composition of which makes it electrically conductive. The physicochemical processes going off in plasma are chemically very active thus allowing realization of chemical reactions which at genuine conditions go off at higher temperatures. Processes in plasma go off at lower temperatures which saves times and electric power considerably. Most of the technological processes in industry use low-temperature plasma as a reagent and energy provider.

In plasma-chemical installations the conversion of electrical energy into heat occurs in vacuum environment directly on the treated surfaces with minimal wastes. Vacuum is a heat insulator which results in considerable energy saving.

Nitriding process is carried out using a low-frequency discharge. As a technology, it is relatively well known and widely used worldwide including in Bulgaria. In contrast, in Bulgaria the deposition of CVD plasma assisted layersis in fact underdeveloped although it would give new opportunities for improving the quality of parts in various spheres of industrial manufacture. In order to effectively combine the above processes, the company expects both processes to take place in the same working chamber without moving the processed samples. This is the so called duplex technology used in installations which allow the consecutive deposition of nitrogen-containing diffusion layer as a base and CVD, corrosion and wearproof additional layers. This way, the energy consumption and the processing time are significantly reduced and the performance of the processed parts and instruments is considerably improved.

The main advantages of energy efficient management of the vacuum duplex technologies are:

• Lack of oxidation;
• Energy saving
• Significant reduction of carbon and other harmful gas emissions;
• Repeatedly increased hardness;
• Excellent wear resistance;
• Reduced consumption of process gases;
• Lack of deformations;
• No need of additional machining;
• Low cost price;
• Short treatment;
• Reproducible results and better control;
• Excellent hygiene and working conditions – the process is not toxic and meets all modern requirements for environmental protection;
• Completely clean process.

APPLICATION OF PLASMA TECHNOLOGY

Thin layer deposition on different parts in weakly ionized plasma by means of duplex processes can be used in modern high-tech manufacturing. With their unique characteristics, different layers allow extending the operating life of parts and tools and help to improve the quality of manufactured products.

Plasma technology is used to develop environmentally friendly, green industries, even where the use of toxic gases and mixtures is necessary. Plasma technology is used in all modern high-tech industries:

• Microelectronics – for plasma etching, plasma deposition of nanolayers, synthesis of carbon nanotubes with unique qualities, ion implantation, etc.;
• Machine building – forcutting and welding of metals and alloys, processing and modification of metal and dielectric surfaces of shafts, axles, tools for cold rolling and deep drawing, cutting tools (cutters, drills, taps, broaches, countersink bits)
• Biomedicine – treatment of food and tissues, sterilization of medical instruments and heat-sensitive materials;
• Automobile industry –crankshafts, camshafts, gears, cylinder shirts, valves, synchronizers;
• Aluminium industry – molds for casting and downloading profiles;
• Military industry;
• Power engineering – turbines, shafts, axles, gears;
• Blacksmiths and press industry – all kinds of stamps for forging and pressing;
• Casting industry – forms for molding under pressure;
• Plastic industry – feeding worms, cylinders, tools extruders, dies;
• Powder metallurgy – gears, bushings, synchronizers;
• Ecology – disposal of toxic substances and waste

Creation and development of algorithms for energy-efficient management of plasma assisted duplex processes leads to development of energy saving technologies. It also promotes methods for smart management in energy saving aspect and thermodynamic process improvement in particular.