MODEL OF RELATION BETWEEN DAMAGES DUE TO DYNAMIC AND QUASI-STATIC LOADINGS: APPLICATION TO WOVEN SIC/SIC COMPOSITE PUNCTURING

This research objective is to estimate a model of relation between quasi-static and speed dynamic damages of a woven SiC/SiC composite, and, to analyze tensile strength residual energies. The goal is to predict the material damage degree produced by dynamic loading knowing one caused by static loading and conversely. V. Herb and al. and; Bhatt and Choi have respectively tested static and impact puncturing into this composite. Then tensile tests were undertaken on the punched and blank specimens. Statistic analysis of quotients damage factors we calculated show that at less quasi-static puncturing energy Ea= 0.05J, the average proportional constant is C0.05=24 between the two types of puncturing within the confidence interval I0.05= [12; 400] at 99%. And at 95% confidence, the impact damage of the woven SiC/SiC is at least 15 times and at more 60 time static damage. And when quasi-static punching energy increases up nearest the dynamic one, the confidence intervals are: : I=I0.25∩ I0.75 =[2; 4] and I=I0.25∩ I0.75 =[2; 2.5] at 99% and 95% confidence respectively for C0.25= 3 and C0.75=1.22 averages. The proportional constants approximate are thus low. Also, punching energies of woven SiC/SiC before tensile tests and tensile strength residual energies move in contrary directions. And tensile strength residual energy on impacted specimens is inferior to one obtained on specimens punched by quasi-static loading.