Paying by work of the modes of the lazer strengthening of the steel and alloys 08C18N10T, 12X1MF, St20 ,Zn6 and K108, intended for the fabrication of  details of the highwarm-up liqued-gate high pressure.
                    (Detail of coolling sidebar of the Atomic Power stations)

   When processing the material by lazer radiating depending on density of flow of beam energy of possible the strengthening of material without flashing of surfaces only to the account of quick heating and coolling and with flashing of surfaces. In the last case area of lazer influence is kept as an area of termal influence, so and area of melted and quickly a crystallize material, sometimes this material are alloying by additional elements. For strengthening of one material of sufficiently creation on their surfaces of area of termal influence, beside strengthening of other material  is possible to obtain only under alloying. As far as beforehand is not known, for what material what mode more preferred, on the first stage of working all material were processed in the mode alloying, to on results of studies of features of areas alloying and termal influence possible was do preliminary findings on the required mode of processing.

 A mass bars from specified material were processed by infrared radiating CO2-a lazer with power
1 kWt under a layer of a technological liquid at velocities of moving a ray on surfaces of material
0.5  cm/ sec . Inflict both separates grooves, and at arm's length friend from the friend, for the reason studying a possibility of annealing following passages of lazer, as well as with the imposition (overlapping) areas of lazer influence. Under such mode of processing an area of lazer influence has in the transverse section a width not less 1 mm and depth not less 0,5 mm.

Results of the lazer influence on separate material.

Steel 20.

Source structure - a ferrite + pearlite, microhardness HV = 170-270 kG/mm a  mm.

Area of lazer influence has the lens form with the area flashing in central part and area of termal influence in peripheral. Area flashing has a martensite structure  with microhardness
410-570 kG/mm a mm. Under greater velocities of moving a ray because of smaller sizes and, accordingly greater velocities of coolling off microhardness of area flashing increases before
560-790 kgses/mm a mm.

Area of termal influence has a variable structure from martensite-ferrite to ferrite-pearlite with the clarification pearlite.Microhardness of area - 410-570 kG/mm a mm, i.e. such as in the area of flashing under small velocities of moving a ray.

At the scan by the ray with the step 1 mm (Pic. 1) occurs an imposition of areas of lazer influence with the termal influence of following passages on already educated areas of influence because of what microhardness near surfaces changes from 370 kG / mm a mm beside borders of preceding area before 790 kG / mm a mm in the area centre of lazer influence.

As far as structures and hardness of the flashing area and areas of termal influence of close, for  strengthening of the steels 20 sufficiently processing without flashing surfaces.

12X1MF.

Source structure - a ferrite + perlite, microhardness is 190-240 kG / mm a mm.

Area of lazer influence has an the flashing area  with the martensite structure and area of termal influence with the variable structure (Pic. 2). The flashing area  has a flaky structure, that speaks of its alloying forming technological liquid to the account of the convective mixing of the meltŗ. However microhardness of the flashing area and areas of termal influence alike - 350-450 kG / mm a mm.
At the imposition of areas in the process of scan termal influence of following passages on preceding is not observe.

Preferred cut lazer processing follows consider a processing without flashing of a surfaces.

EK 108.

Source structure - single-phase (the alloying ferrite ) with point including, microhardness is
290-470 kG / mm a mm.

Area of lazer influence has only  the flashing area , area of termal influence is absent. MicroHardness of the flashing area is not distinguish from source, but has a smaller scatter of values, that speaks of more high homogeneity. The flashing area has no including, structure its does not etching. The flashing area are more best polishing , than beside the source structure, probably, because of more uniform fine-grained structure. At the scan with the imposition of areas beside surfaces of material will be form utter uniform layer by the thickness near 0,5 mm.

Preferred cut processing this material is a processing with flashing of a surfaces.

Zn6.

Source structure - the austenite with the dispersive including , microhardness 340-500 kG / mm a mm.

Area of lazer influence has both an the flashing area and area of termal influence (Pic.4). MicroHardness in both areas is not distinguish from source. The flashing Area has a flaky structure -a result of convective mixing of a melt. Borders of the grains are not show. Observe rifts, that speaks of embrittle of the flashing areas and origin of powerful sprain voltages.

Area of termal influence has no sharp borders with the main material, is distinguish low etching, absence of the borders of the grain and nearly full absence of cut-in.

Preferred cut processing is a processing without flashing of the surfaces.

08C18N10T.

Source structure -  the austenite, microhardness 200 - 340 kgses/mm a mm.
 The Area of lazer influence has only the flashing area  with more high, than beside bases, etching and such microhardness. The polish are lower,beside bases, so material is not perspective for the lazer strengthening.

Thereby, on the first stage of work was install that preferred cut lazer processing an alloy EK 108 is a processing with flashing of the surfaces, alloy Zn6 and steel 20 and 12X1MF - a processing without flashing, steel 08C18N10T is not perspective in the plan of raising its wear resistance way of lazer influence.

On the second stage of studies were prepare samples with recirculating working areas for undertaking the test on hydraulic presses.Lazer processing of working surfaces of samples was conduct under the layer of a technological liquid in the mode of scan with the step 0,5 mm under under unceasing rotating an a axialy symmetric detail.

Samples steels 20 have show an increased aptitude to the oxidation and low wear capability. Ruining has occurred under the specific load 40  and 60 kG / cm a cm. The most Further work with this will become expedient only at the condition of preliminary creation on its surfaces of the corrosion stability layer.

Samples of alloy Zn6 processed in two different modes, have bear a specific load 500  and
1400 kG / cm a cm accordingly. Beside samples with more low stability on the transverse section was observe area of termal influence with more low etching by the depth before 140 žÍž. Beside the sample with more high stability of area termal action had a thickness 70-100 mkm . Difference is in the behaviour of samples possible to explain that, that in the first even  a mode of processing by the lazer was such a, that had flashing of the fine surface layer not observable on microstructures. As it was shown above, this layer beside Zn6 possesses increased frailty, as brings about destroying under
comparatively low specific loads. In the second event flashing completely is absent, there is only the layer of the termal influence with soluble including  (Pic.5). Presence of the flashing area in the first event are acknowledgement of  a presence in surfaces of sample of one of the technological liquid elements - titanium.