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The paper aims to present an investigation of heating during vapour phase soldering (VPS) on inclined printed circuit board (PCB) substrates. The PCB is a horizontal rectangular plate from the aspect of filmwise condensation with a given inclination setting.

The paper focuses on the measurement of temperature distribution on the PCBs with a novel setup immersed in the saturated vapour space. The measuring instrumentation is optimized to avoid and minimize vapour perturbing effects.

The inhomogeneity of the heating is presented according to the lateral dimensions of the PCB. The inclination improves temperature uniformity, improves heat transfer efficiency; however, a minor misalignment may affect the flow and result in uneven heating.

The results can be implemented for practical improvements in industrial ovens with the use of intended inclination. The improvements may consequently point to more efficient production and better joint quality.

The novel method can be used for deeper investigation of inclination during and can be complemented with numerical calculations. The results highlight the importance of precise PCB holding instrumentation in VPS ovens.

The year 2020 brought a series of previously unknown experiences, events, and life situations to the world. Fear of unknown, uncertainty, unpredictability, and dramatic changes have had a strong impact on all strata and segments of society. We assume that global happenings of the last decade, climate change, pandemic followed by its related strict restrictions mean a determining event for youngsters which fundamentally shapes their lifestyle, future prospects, problem perception, and their generational characteristics as well. In our study, we examine the real-life situation of students at the University of Szeged from numerous aspects, with particular regard to the possible generation-transforming role of climate and quarantine situation, and we also scrutinize to what extent our previous estimations can be verified with data. The online data collection was carried out in the spring of 2021, the sample contains 1195 members. As the result of the data analysis, we indicated that the coronavirus epidemic does not play a leading role in the problem perception of the students, however, their responses about their self-characterization testify on increased perception of crisis phenomena. Although public life and public discourse have been thematized by the coronavirus epidemic since spring 2020, incompetence of politicians and global environmental change are the most serious problems for the students. In the basic dimensions of youth vulnerability namely in the field of education, leisure, and finance, the satisfaction of the students are the lowest. As a result of the restrictive measures, the online activity of the students has further strengthened; instead of silence and apolitical behavior, the students are characterized by a strong public–political interest, increased sensitivity to global problems in the third wave of the pandemic.

The vacuum vapour phase soldering method was investigated by numerical simulations. The purpose of this study was to examine the temperature changes of the solder joints during the vapour suctioning process. A low pressure is used to enhance the outgassing of the trapped gas within the solder joints, which otherwise could form voids. However, the system loses heat near the suction pipe during the suctioning process, and it can result in preliminary solidification of the solder joints before the gas could escape.

A three-dimensional numerical flow model based on the Reynolds averaged Navier–Stokes equations with the standard k-e turbulence method was developed. The effect of the vapour suctioning on the convective heat transfer mechanism was described by the model. Temperature change of the solder joints was studied at the mostly used substrate and component combinations, as well as at different system settings.

In the function of the substrate thickness and the component size, the solder joints can lose large amount of heat during the void reduction process, which leads to preliminary solidification before the entrapped gas voids could be removed.

The results provide setting information of vacuum vapour phase technology for appropriate and optimal applications.

The relationship between low pressure generation and convective heat transfer mechanism during vacuum vapour phase soldering has not been studied yet. The possible negative effects of the vapour suctioning process on the solder joint temperature are unknown.