[Change in the properties of titanium alloys exposed to a stream of high-frequency, low-pressure radiating plasma]. / Izmenenie svoistv titanovykh splavov pod vozdeistviem potoka vysokochastotnoi izluchaemoi plazmy nizkogo davleniia.

The Nitrogen-Argon plasma of a high-frequency low-pressure discharge is proven to be very effective in machining pieces made of titanium alloys. The optimum operating modes are found that improve surface microhardness, reduce surface roughness, increase durability and endurance limits, and do not produce the effect on the residual stress. The operating modes have been tested with great success in machining microsurgical and ultrasonic surgical instruments.

[Soldering of medical instruments with silver-free solders]. / Paika izdelii meditsinskoi tekhniki besserebrianymi pripoiami.

Silver-containing solders may be changed over with copper-phosphor ones when soldering some kinds of medical instruments. The solder PMFOTsr 6-4-0.03 is especially recommended because it is characterized by better technological properties and is commercially available.

[Optimal coefficient of overlap of light spots during laser hardening of medical instruments]. / Optimal'nyi koéffitsient perekrytiia svetovykh piaten pri lazernom uprochenii meditsinskikh instrumentov.

The optimum coefficient of light spot intercepts in the course of laser hardening medical instruments is determined for the case when there are no unirradiated sites on the surface under treatment. The increase in the light spot diameter during irradiation has been shown to be followed by more rapid expansion of the hardened area in comparison with the one of the tempered zone.

[Change in the composition and structure of the metal in the zone of the welded seam of dental drill blanks]. / Zakonomernost' izmeneniia sostava i struktury metalla v zone svarnogo shva zagotovok zubnykh borov.

Composition and structure of metals in the meld zone connecting a dental burr handpiece made of hard alloy BK-6 with a shank made of steel 20X13 are examined by the X-ary microanalyzer MS-46 and the X-ray diffractometer "dPOH-2". Representative interdiffusion processes of alloy components into steel and, converserly, iron from steel into hard alloy are found. After melding, the transition layer has been shown to represent the cobalt-iron solid solution with variable concentration of the components through the layer, tungsten carbid particles being uniformly spread all over the metallic matrix. The phasic composition change is analysed in the course of material welding. The enrichment of stell melt with carbon of tungsten carbid results in the formation of gamma-Fe phase in the meld zone. The failure of burr blanks is noted to occur at the interface of the second (10-20 micrometer) and the first (130-140 micrometer) zones. The increase in the concentration of both iron and iron-containing phases--alpha-Fe, gamma-Fe, Fe3W3C--at the surface of steel fracture is responsible for the failures.

[Hardening of dental instruments]. / Uprochnenie stomatologicheskikh instrumentov.

The possibility of prolonging the service life of stomatological instruments by the local hardening of their working parts is discussed. Such hardening should be achieved by using hard and wear-resistant materials. The examples of hardening dental elevators and hard-alloy dental drills are given. New trends in the local hardening of instruments are the treatment of their working parts with laser beams, the application of coating on their surface by the gas-detonation method. The results of research work and trials are presented.

[Reinforcement of the operating elements of medical instruments]. / Uprochnenie rabochikh élementov meditsinskikh instrumentov.

Reinforcement processes were analysed to assess the possibility of their use for the medical apparatus production. It was shown that one of the ways to make medical instruments more durable is the reinforcement of their operating surfaces with wear-proof, corrosion-resistant and hard materials by means of soldering, sputtering and fuse on.