PSI - Issue 59

Victor Aulin et al. / Procedia Structural Integrity 59 (2024) 428–435 Victor Aulin et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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Dissipative secondary structures, which spontaneously form during friction as a result of the interaction of the surface layers of the materials of the tribo-conjugation parts, the oil and the external environment, are responsible for the modes of friction, the values of the wear intensity parameters, and the contact electrical resistance of the tribo-conjugation samples and parts. Dissipative secondary structures have extreme anti-frictional (frictional) and strength characteristics that normalize the processes of friction and wear of tribo-conjugation samples, protect the original material of parts from mechanical and physico-chemical destruction (fig 5).

Fig. 5. The appearance of friction surfaces, sections of the surface layers of the samples and schemes of destruction of dissipative secondary structures of the first type (а, b, c) and dissipative secondary structures of the second type (d, e, f); а, d – electronic microphotos; b, e – construction diagrams; c, f, - destruction schemes. The proposed method, based on determining the relative time of existence of continuous oil layers and dissipative secondary structures, allows to control the process of formation of stable dissipative secondary structures. The initial parameter is the value of the contact electrical resistance of the triboconjugation of the samples, which is compared with a given level and when it exceeds the triboconjugation of the samples (parts), it is completely separated by dissipative secondary structures and oil layers, in the opposite case - their absence. Relative time the existence of continuous oil layers re t and dissipative secondary structures is determined as a fraction of the time division of the presence of oil layers and dissipative secondary structures that separate the triboconjugation of samples (parts),    n i ren re t t 1 for the reference time ref t , during which is determined re t :

100% 100% f r t ref n x 

t ref t re

 

(1)

To control the mode of friction and determine the relative time, a basic block diagram of the device has been proposed (Fig. 6). According to the block diagram (fig. 6), resistor 2 and tribocoupler of samples (parts) 6 are connected in series in the circuit of power source 1. In parallel with the tribo coupling of samples (parts), a comparator 3 is connected, which controls the starting generator 4. The output of the generator 4 is connected to the input of the frequency counter 5. When continuous oil layers and dissipative secondary structures are formed in the process of friction and wear in the zone of frictional contact, the voltage drop on the tribocoupler of samples (parts) 6 will be higher than the preset level in the comparator 3, which causes the appearance at its output of an additional voltage necessary to