Визначення порогових значень технологічних параметрів лазерного зміцнення на основі методів поліаргументних систем
| Autor: | Nataliia Meranova, V. L. Yurchuk, V. G. Prokopov, Ju. V. Sherenkovskiy, N. P. Polozenko, Nataliia Fialko |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Materials science
Cutting tool загартування променем лазера математичне моделювання процеси теплопереносу різальний інструмент Heat transfer problem Monotonic function Sharpening Mechanics Laser law.invention law Threshold velocity General Earth and Planetary Sciences lcsh:SD1-669.5 Laser heating lcsh:Forestry General Environmental Science Dimensionless quantity |
| Zdroj: | Науковий вісник НЛТУ України, Vol 29, Iss 6, Pp 92-97 (2019) |
| ISSN: | 2519-2477 1994-7836 |
| Popis: | The article is devoted to the determination of the threshold values of technological parameters during laser hardening of the cutting tool. This determination was based on solving a volume quasi-stationary heat transfer problem for a wedge-shaped region in the presence of a normally-distributed laser heating source moving at a constant velocity. To solve this problem, the polyargument systems method was used, which is characterized by high adaptive properties with respect to the multidimensionality factor. The provisions that are the basis for constructing these methods are given. Using the method of polyargument systems, the threshold values of the technological parameters were obtained for the following three negative situations observed in the practice of hardening the cutting tool: 1) penetration of the cutting edge itself; 2) penetration of a zone adjacent to the surface to be treated and located at a distance from the cutting edge; 3) separation of the hardened zone from the cutting edge (i.e., in this case, the actual cutting edge is not strengthened). For the first of these situations, the extreme nature of the dependence of the dimensionless threshold velocity of the laser beam Pen1 on the distance a* between the cutting edge of the tool and the centre of the beam is established. The explanation of the obtained dependence is given on the basis of the analysis of the action of a number of competing factors. For the second and third of the considered negative situations, the dependences of dimensionless threshold velocities Pen2 and Pen3 on the value of a* are monotonically decreasing. The fact of insignificant dependence of the magnitude Pen2 on the quantity a* is established for relatively large values of a*, which is a consequence of the manifestation of the effect of localization of the influence of the unheated surface of the instrument on its thermal state. The regularities of the influence of the sharpening angle of the cutting tool on the threshold values of technological parameters are revealed. It is shown that the threshold values of the dimensionless velocity are the larger, the smaller, all other conditions being equal, the sharpening angle of the wedge. The obtained threshold values of the parameters should be used when selecting the technological modes of hardening the cutting tool with a laser beam. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|