Experimental Study on Static Compression Performance of Multilayer Superimposed Honeycomb Paperboard II

2. Experimental study on static compression characteristics of two-layer superposed honeycomb paperboard

2.1 Static compression test

The same type of honeycomb paperboard was used for the test. The cardboard sample area was A=100mm×100mm, the thickness was t=20mm, the paper core was 130g/m2, the side length of the honeycomb hexagon was 10mm, the ambient temperature was 26°C, and the relative humidity was R=79 %. The experimental equipment is an automatic computer-assisted pressure testing system for RMT. The experiment was conducted using the A method. The specimen is gradually increased in the thickness direction at a speed of 6 mm/min. The experimental equipment can automatically and continuously measure and record the pressure and deformation change process and finally automatically draw the pressure (F)-deformation (δ) characteristic curve. The static compression characteristics of F-δ and σ-ε at the low rate of superposition and combination of two layers of 20mm thickness honeycomb paperboard obtained from the test are shown in Fig. 3, and the curves of the large-rate static compression characteristics F-δ and σ-ε are shown in Fig. 4.

2.2 Static Compression

Characteristic analysis through analysis

Figure 3, Figure 4 shows:

1) The static compression characteristics obtained from the test are clearly divided into 2 periods, each of which is consistent with the static compression characteristics of one of the layers;

2) The two layers of cardboard are subjected to four stages of compressive properties in order from the smallest to the largest, and this is also verified during the test.

3, the conclusion

Through the above tests and analysis, the following conclusions can be obtained:

1) In the process of compressing multi-layer superimposed honeycomb paperboard, when the yield strength of each layer is different (that is, the stress peak in the elastic phase), the minimum layer of yield strength should be first yielded and destroyed, and then the other layers should follow the order of yield strength from small to large. Followed by yield, experienced elastoplastic, plastic and compaction deformation stages;

2) The compression characteristic curve of multilayer superposed honeycomb paperboard is obviously periodic, and each cycle is consistent with the static compression characteristic of one of the layers;

3) The periodic pulsation in the compression characteristic curve of the multilayer superimposed honeycomb paperboard will have an adverse effect on its buffering performance and should be taken into account during use. (Author: Zhang Anning ROCKETS Liu Xiao Yun Yao Leijiang)