Конструкція, апаратна та програмна реалізпація системи управління тепловим режимом установки для високотемпературних випробувань

A description of the design, control system, and software implementation of the thermal mode control of the experimental creep testing machine developed at the National Technical University "Kharkiv Polytechnic Institute" is given. As a result of testing the automated temperature control system, the main characteristics of the system were established. It was determined that the range of the temperature regulation task is from 0 to 999°С. The working range of heating is from 100 to 500°С. It was established that when the conditions for placing the specimen and ensuring the required thermal insulation of the heating chamber are met, the absolute value of the average temperature adjustment error has a value that does not exceed ±2°С. The root-mean-square value of the adjustment error is no more than ±1.6°С. It was determined that the stability of temperature maintenance depends on the location of the specimen: in the central zone of the chamber, the values of temperature fluctuations are smaller than when the specimen is placed at the bottom. The cycle time of measuring and adjusting the temperature regime is 1.0012 seconds. The power of the heaters is 2x1200 W (in phase switching) and 2x3500 W (in linear mode). The microcontroller used in the system has resources for connecting additional modules and primary converters, which enables expanding the functionality of the system by organizing additional measurement channels. The first results of testing in the study of creep of plane specimens made from aluminum alloys are presented. The character of the creep curve obtained from the strain measurements of the specimens fully corresponds to its classical forms with three sections. A view of a fragment of the destroyed specimen is provided. The modular design, versatility and high technical characteristics of the system and the testing machine as a whole allow its use in various experiments in research projects and in the educational process.