PSI - Issue 20

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M.P. Lebedev et al. / Procedia Structural Integrity 20 (2019) 81–86 M.P.Lebedev et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 1. Histogram of the distribution of mechanical indicators 3300 sets of RMB after 1-23 years of climatic aging

If after 1-3 years of exposure under natural climatic conditions, the mechanical indicator of PCM has changed by more than 10-20%, and then the probable cause may not be the aging of PCM as shown by Kablov (2018), but a methodological disadvantage when performing measurements as pointed by Startsev (2018). The experience shows (Fig. 2) that with correct mechanical measurements, the duration of exposure t increases, and the index R changes monotonously in accordance with the equation.

at bt R R e R e R .

(2)

1

2

To explore the influence of ultrafine silicon carbide powders on the properties of epoxy resin they produced some samples for compression tests (GOST 4651- 2014), bending tests (GOST 4648- 2014), impact strength tests (GOST 4647- 80) with different degree of filling, range, chosen in response to the equivalent results of the studies, conducted with ultrafine fillers of different nature. The tests were carried out on the universal machine INSTRON 3369 with the highest extreme loads 50 kN, the value of graduation 0,01 kN and strength measurer tolerance ±0,1 %. The results of testing can be seen in Fig. 2 - 3.

Fig. 2. An example of a monotonous decrease in the mechanical index due to the destruction of the polymer matrix