zldmЗаводская лаборатория. Диагностика материаловIndustrial laboratory. Diagnostics of materials1028-68612588-0187ООО «Издательство «ТЕСТ-ЗЛ»10.26896/1028-6861-2025-91-5-67-76zldm-2496Research ArticleМЕХАНИКА МАТЕРИАЛА: ПРОЧНОСТЬ, РЕСУРС, БЕЗОПАСНОСТЬMATERIALS MECHANICS: STRENGTH, DURABILITY, SAFETYИсследование возможностей метода инструментального индентирования для определения механических свойств полиэтиленаA study of applicability of instrumented indentation method to determine the mechanical properties of thermoplasticВиноградоваА. А.VinogradovaA. A.

Анна Александровна Виноградова

199106, г. Санкт-Петербург, 21-я линия В.О., д. 2

Anna A. Vinogradova

2, 21st Line V.O., St. Petersburg, 199106

shchiptsova.katya@yandex.ruГоголинскийК. В.GogolinskiyK. V.

Кирилл Валерьевич Гоголинский

188300, Ленинградская обл., г. Гатчина, мкр. Орлова роща, д. 1

Kirill V. Gogolinskiy

1, mkr. Orlova roshcha, Gatchina, Leningradskaya oblast’, 188300

ЩипцоваЕ. К.ShchiptsovaE. K.

Екатерина Константиновна Щипцова

199106, г. Санкт-Петербург, 21-я линия В.О., д. 2

Ekaterina K. Shchiptsova

2, 21st Line V.O., St. Petersburg, 199106

Санкт-Петербургский горный университет императрицы Екатерины IIРоссияEmpress Catherine II St. Petersburg Mining UniversityRussian FederationНИЦ «Курчатовский институт» — ПИЯФРоссияSt. Petersburg Nuclear Physics InstituteRussian Federation2025270520259156776Copyright © Виноградова А.А., Гоголинский К.В., Щипцова Е.К., 20252025Виноградова А.А., Гоголинский К.В., Щипцова Е.К.Vinogradova A.A., Gogolinskiy K.V., Shchiptsova E.K.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.zldm.ru/jour/article/view/2496

Рассмотрен метод инструментального индентирования как эффективный инструмент для изучения механических свойств полиэтиленов. С помощью данного метода можно определить такие свойства материалов, как твердость, модуль упругости и реологические характеристики. Приведены примеры использования метода инструментального индентирования для изучения свойств различных видов полимерных материалов, описаны параметры, которые влияют на результаты измерений. Экспериментально исследованы возможности метода на примере определения характеристик полиэтилена высокой плотности, который используется при производстве газовых трубопроводов. Результаты подтвердили применимость данного метода при изучении свойств полиэтиленовых (ПЭ) труб газопроводов для диагностирования их технического состояния. Исследованы образцы труб, длительное время находящихся в эксплуатации, а также образец новой трубы. Выявлено, что у образцов полиэтилена разного срока эксплуатации значения твердости как показателя сопротивления пластической деформации при статических нагрузках достаточно близки, в то время как реологические свойства существенно отличаются. Эту особенность необходимо принимать во внимание при проведении различных механических испытаний, поскольку скорость увеличения нагрузки в ходе таких испытаний будет существенно влиять на их результаты. Установлено, что значения твердости и модуля упругости уменьшаются с увеличением времени выдержки индентора под нагрузкой из-за релаксации напряжений в деформированной области под индентором. Рассмотрено влияние структуры полиэтилена на его механические свойства. Также выявлено, что модуль упругости образцов полиэтилена кратно возрастает при изменении степени кристалличности от 48 до 56 %. Проведенная работа показала перспективность и эффективность использования метода инструментального индентирования для анализа упругопластических и реологических свойств полиэтиленов, а также их связи с кристаллической структурой.

The article deals with the method of instrumental indentation as an effective tool for studying the mechanical properties of thermoplastics. The method allows to determine such material properties as hardness, modulus of elasticity, rheological characteristics. The paper presents a review of examples of using the method of instrumental indentation to solve research problems in studying the properties of various types of polymeric materials, describing the parameters that affect the results of measurements. Analyses and experimental studies of the method’s capabilities were carried out on the example of high-density polyethylene, which is used in the production of gas pipelines. The results showed the applicability of this method in studying the material properties of polyethylene (PE) gas pipeline pipes for diagnosing their technical condition. In this work, samples that have been in service for a long time and a sample of new pipe were investigated. It has been revealed that the hardness values of polyethylene samples of different service life as an indicator of resistance to plastic deformation under static loads are quite close, while the rheological properties differ significantly. This peculiarity should be taken into account when conducting various mechanical tests, since the rate of load increase during such tests will significantly affect their results. It was found that the values of hardness and modulus of elasticity decrease with increasing indenter dwell time under load due to stress relaxation in the deformed region under the indenter. The influence of polyethylene structure on its mechanical properties is considered. It is also revealed that the modulus of elasticity of polyethylene samples multiply increases when the degree of crystallinity changes from 48 to 56%. The article describes the prospectivity and efficiency of using the method of instrumental indentation to analyse the elastic-plastic and rheological properties of thermoplastics, as well as their relationship with the crystal structure.

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The authors declare that there are no conflicts of interest present.