Experimental study and statistical optimization of fabrication parameters affecting the flexural strength of composite grid-stiffened panels

The purpose of this study is to investigate the effect of effective manufacturing parameters on the flexural strength of composite mesh panels by experimental-statistical method. To achieve this goal, after studying the methods of making composite mesh panels and recognizing the parameters that are effective in making these panels, and considering the available facilities, four parameters of firing cycle, pressure during firing, resin temperature and fiber tension as the most important effective parameters They were selected to build these panels. In the next step, by selecting three levels for each parameter using Taguchi experiment design method from among 81 possible construction modes, 9 Taguchi proposed modes for constructing 9 panels were considered. After fabrication of these samples, using the methods of preliminary analysis and analysis of variance, the optimal construction conditions and the effect of each parameter on the strength were determined and the results were compared with the output of qualitative test design software. Optimal manufacturing conditions are 4 cycles of baking cycle at 80 °C and 2 hours at 160 °C, 3 bar pressure, 60 °C resin impregnation temperature and 70 N.m fiber stretch. Also, fiber tension with 73.34% had the highest and pressure parameter with 0.99% had the least effect on the response and the effect of resin temperature and curing cycle on the response were 11.99% and 11.67%, respectively.