MODELS OF TECHNOLOGICAL DEFECTS OF CONDUCTIVE PATTERNS OF PRINTED CIRCUIT BOARDS 

Danilova Evgeniya Anatol'evna, senior lecturer, sub-department of radio equipment design and production, Penza State University (440026, 40 Krasnaya street, Penza, Russia), siori@list.ru
Kochegarov Igor' Ivanovich, candidate of technical sciences, associate professor, sub-department of radio equipment design and production, Penza State University (440026, 40 Krasnaya street, Penza, Russia), kipra@mail.ru
Trusov Vasiliy Anatol'evich, candidate of technical sciences, associate professor, sub-department of radio equipment design and production, Penza State University (440026, 40 Krasnaya street, Penza, Russia), trusov_v@mail.ru

396; 621.8

10.21685/2307-4205-2017-2-10

Background. Some technological defects of printed circuit boards, successfully passed the control procedure, can potentially develop into critical defects in the presence of external and (or) internal influences of a different kind. The complexity of defect development processes leading to PCB failures urgently requires the creation and improvement of informationmeasuring systems not only detection, but also prediction of the development of PCB defects, taking into account external influences. To solve this problem, it is necessary to analyze the models of the development of technological defects that allow predicting the development of a defect and to prepare mathematical models for their investigation.
Matherials and methods. The methods of system analysis, the theory of mathematical and simulation modeling, the analysis of technological systems are used in the article.
Results. The paper presents four models for determining the theoretical stress concentration factor of several types of common defects that take into account the decrease in the strength of the elements of the PP. For each model, an estimate of the indicators determining its quality is given.
Conclusions. Technological defects of the conductive PP pattern are stress concentrators, leading to a decrease in strength during  peration. Formulas relating the geometric dimensions of the defects and the stress concentration coefficient corresponding to the 4 types of defects necessary for determining the number of cycles before failure, the fatigue strength factor, and the time to failure are given. The selected models for determining the values of the stress concentration factor can be used as a database for detecting defects in printed circuit boards

printed circuit board, printed conductor, technological defect, mathematical model, mechanical stresses