International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The optimum ranges of the electron beam parameters change (density of heat exposure and speed of movement), within which there is a substantial improvement (more than 2 … 3 times) of the basic properties of the surface layers of the optical elements are found. The tests of the optical windows of laser rangefinders under intensive external heating and hemispherical optical fairings of IR devices at supersonic blowing by air flow and axisymmetric rotation that simulate real operating conditions, have shown that in the case of processed by electron beam optical windows and fairings it reduces the number of their destruction and increases the reliability of the devices during the operation, taking into account the impact of external-heat.

The results of experimental studies to improve the properties of the surface layers of the elements of optical glass (K8, K108, 6 8 2 K208, BK10, TF110) after their processing by mobile electron beam with density of heat exposure F = 7·10 …8·10 W/m and n -3 -2 displacement speed V = 5·10 …5·10 m / s (a reduction of residual microroughness height at the surface from 4 … 6 nm (unprocessed elements) to 0.5 … 1 nm (processed elements), the occurrence of melted layers of thickness up to 250 … 300 microns with a modified structure, which is close to the quartz glass) are presented. It was found that the improvement of these properties increases the resistance of elements to external-heat: an increase in 1.3 … 1.7 times of the critical value of external heat fluxes and the time of their exposure, the excess 5 7 of which leads to the destruction of elements and damage to the test instrument turndown external pressure 10 …10 Pa; increasing the maximum permissible values of thermal stress in the elements from 20 … 40 MPa to 90…100 MPa heating temperatures 300 … 1200 K;an increase of the probability of failure-free operation in the 2 … 2.5 times by increasing the speed of the external heating from 100 K / s to 400 K / s.

The results of experimental studies of the influence of electron beam parameters (density of heat action, the speed of movement) on the properties of the surface layers of the elements of optical ceramics (changes in the structure of the material through the thickness of the element, the amount of surface microhardness, values of residual thermal stresses in the layers, the thickness of the hardened layers, their stability to external thermal and mechanical stresses) are. The optimum range of parameters of the beam, within which there is improvement in the properties of the surface layers of the optical elements, which leads to the increase of the basic technical-operational characteristics of devices based on (reliability, lifetime) in the conditions of use of devices with the influence of external-heat are established.

The results of experimental studies to improve the properties of the surface layers of the elements of optical glass (K8, K108, K208, BK10, TF110) after their processing by mobile electron beam with density of heat exposure Fn = 7·10⁶…8·10⁸ W/m² and displacement speed V = 5·10^-3…5·10^-2 m/s (a reduction of residual microroughness height at the surface from 4 … 6 nm (unprocessed elements) to 0.5 … 1 nm (processed elements), the occurrence of melted layers of thickness up to 250 … 300 microns with a modified

structure, which is close to the quartz glass) are presented. It was found that the improvement of these properties increases the resistance of elements to external-heat: an increase in 1.3 … 1.7 times of the critical value of external heat fluxes and the time of their exposure, the excess of which leads to the destruction of elements and damage to the test instrument turndown external pressure 10⁵…10⁷ Pa; increasing the maximum permissible values of thermal stress in the elements from 20 … 40 MPa to 90…100 MPa heating temperatures 300 … 1200 K; an increase of the probability of failure-free operation in the 2 … 2.5 times by increasing the speed of the external heating from 100 K / s to 400 K / s.

In the article are presented the results of researches of action of electronic ray on optical elements. The analysis of surfaces of elements before and after a beam-processing the method of atomic-force microscopy shows that in first case the height of microburries makes 50…60 nm, and in second case goes down to the level of 0,5…1 nm. Influence of parameters of electronic ray is set on the height of microburries: the increase of closeness of thermal influence of ray in 6 times results in diminishing of height of microburries in 3…4 time, diminishing of rate of movement of ray in 5 times results in diminishing of height of microburries in 5…6 times. It is shown that by optimization of the modes of beam-processing of elements it is possible substantially to improve (to 50…60%) properties of its superficial layers and basic operating descriptions of devices. Thus probability of destruction of elements and death devices in the conditions of intensive external thermal influences, devices can undergo that at their storage, portage and application, diminishes in 1,5…2 time.