Markov A.M., Nekrasov V.N._et.al._2020 Vol.22_No.2

OBRABOTKAMETALLOV Vol. 22 No. 2 2020 13 TECHNOLOGY References 1. Stepanov A.A. Obrabotka rezaniem vysokoprochnykh kompozitsionnykh polimernykh materialov [Cutting of high-strength composite polymeric materials]. Leningrad, Mashinostroenie Publ., 1987. 176 p. [In Russian]. 2. Veazey D., Gomez E.D., Hsu T. Next generation high-performance carbon fi ber thermoplastic composites based on polyaryletherketones. Journal of Applied Polymer Science , 2017, vol. 134, iss. 6, p. 44441. DOI: 10.1002/ app.44441. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2020 vol. 22 no. 2 pp. 6–15 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2020-22.2-6-15 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov Study of the In fl uence of Technological Parameters on the Strength of a Threaded Connection in Carbon Fiber Parts Andrey Markov a , Vyacheslav Nekrasov b, * , Azhar Salman c , Sergey Gayst d , Jian Su e I.I. Polzunov Altai State Technical University, 46 Lenina avenue, Barnaul, Altai region, 656038, Russian Federation a https://orcid.org/0000-0002-3101-9711 , andmarkov@inbox.ru , b https://orcid.org/0000-0002-8122-4641, sla44@mail.ru, c https://orcid.org/0000-0002-6584-1439, azharmansoor76@gmail.com, d https://orcid.org/0000-0001-8697-6263, sergei-gaist@mail.ru , e https://orcid.org/0000-0001-5120-3623, 278507234@qq.com ARTICLE INFO Article history : Received: 14 March 2020 Revised: 02 April 2020 Accepted: 23 April 2020 Available online: 15 June 2020 Keywords : Internal thread Drilling Threading modes Threaded strength Factor experiment Carbon fi ber parts ABSTRACT Introduction . Composite materials are widely used in mechanical engineering and instrument making. Composites have a low speci fi c gravity with high strength and wear resistance and are used in civil and military equipment. At the same time, the existing technologies for producing composites do not provide suf fi cient indicators of the parts accuracy; therefore, machining is still the main way to achieve the required quality. Despite the wide technological capabilities of blade processing, high abrasive properties and heterogeneity of the carbon fi ber structure imposes a number of limitations and complicates the choice of processing parameters, especially in the manufacture of internal threads. In addition to the processing modes, the diameter of the pre-drilled hole has a signi fi cant effect on the quality of the threaded connection. Despite the studies already carried out in the fi eld of machining of carbon fi ber reinforced plastics, a number of questions have not received suf fi cient study. The purpose of the work is to obtain a relationship between the parameters of the hole and thread processing, as well as the diameter of the hole and the quality of the threaded connection to ensure the speci fi ed strength characteristics of the threaded connection. A method is proposed and the results of an experimental study of the strength of a threaded joint, consisting of a carbon fi ber part with an internal thread and a structural steel screw, are provided in the axial direction with uniform indentation of the screw with the determination of the maximum fracture resistance force. Research methods : a full factorial experiment is conducted for threaded joints with diameters M6, M7 and M8 to identify the dependence of the strength of the threaded connection on such operating parameters as cutting speed and feed rate during drilling and cutting speed when threading. To control the maximum force of fracture resistance, characterizing the strength of the threaded connection, a universal electromechanical testing machine model Instron-3369 is used. Results and discussion . A comparative analysis of the test results shows that for samples with thread diameter M6, the maximum fracture resistance force is from 5.7 to 6.4 kN. But with a minimum supply of drilling in combination with a minimum speed of threading, the maximum load force does not exceed 3.8 kN. Similar results are obtained when testing samples with thread diameters M8 and M10. For citation: Markov A.M., Nekrasov V.N., Salman A.M., Gayst S.V., Su J. Study of the in fl uence of technological parameters on the strength of a threaded connection in carbon fi ber parts. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2020, vol. 22, no. 2, pp. 6–15. DOI: 10.17212/1994-6309-2020-22.2-6-15. (In Russian). ______ * Corresponding author Nekrasov Vyacheslav N. , Ph.D. (Engineering), Associate Professor I.I. Polzunov Altai State Technical University, 46 Lenina avenue, 656038, Barnaul, Altai region, Russian Federation Tel.: 8 (3852) 29-08-94, e-mail : sla44@mail.ru