
АЛГОРИТМ НАЗНАЧЕНИЯ РЕЖИМОВ ТЕРМОИМПУЛЬСНОЙ ОБРАБОТКИ С УЧЕТОМ ПРОЧНОСТНЫХ ОГРАНИЧЕНИЙ
Author(s) -
Сергей Игоревич Планковский,
Ольга Владимировна Шипуль,
Евгений Владимирович Цегельник
Publication year - 2018
Publication title -
avacìjno-kosmìčna tehnìka ì tehnologìâ/avìacìjno-kosmìčna tehnìka ta tehnologìâ
Language(s) - English
Resource type - Journals
eISSN - 2663-2217
pISSN - 1727-7337
DOI - 10.32620/aktt.2018.4.09
Subject(s) - thermal , plasticity , action (physics) , materials science , anisotropy , residual stress , distortion (music) , computer science , thermal expansion , resource (disambiguation) , structural engineering , mechanical engineering , mechanics , composite material , engineering , physics , amplifier , computer network , optoelectronics , cmos , quantum mechanics , meteorology
The analysis of the applicability of the finish thermal energy and thermal pulse treatment by detonable gas mixtures to various parts determine the need to take into consideration the strength constraints, which in turn is the subject matter of investigation when treatment settings are determined. The goal of the article is to develop an algorithm of settings assigning for thermal pulse finishing taking into account strength constraints of a part. In this regard, as the research tasks, existing methods for designating treatment regimes, including clarifying approaches, have been analyzed. The most probable factors affecting the possible destruction of parts under the action of thermal pulse loads are considered and the need for their comprehensive accounting is determined. The following results are obtained. Evaluation of the distortion possibility of the part shape in places with a minimal wall thickness should be performed by follow condition: plastic deformations in metal must not be reached in the dangerous zones during processing. When the maximum time of thermal pulse action is determined, provided that the residual deformations in the workpiece surface layer are present, it is necessary to amount the anisotropy of the linear thermal expansion coefficient and to apply the Johnson-Cook model, which calculates the dynamic yield strength of the material. Subject to the plasticity resource is exhausted, the possibility of the material destruction must be evaluated according to the criterion of the plasticity resource using as the ratio of the accumulated deformation degree to the maximum allowable state under a certain scheme. For parts with structural heterogeneity, it is suggested to define the possibility of developing cracks from internal pore zones, by determining the values of the stress intensity factor or the J-integral and comparing them with critical values. The following conclusions are formulated. An algorithm for assigning settings for thermal pulse finishing has been developed. The proposed approach ensures to determine agreed settings of the necessary energy of equipment to treat parts with specified qualimetry parameters and the sufficient one from the standpoint of strength requirements. Stability of processing quality should be provided by systems for filling the mixture, burning and releasing the products of combustion of automated thermal pulse equipment.