Oxidation behavior of a Cr3Si-Cr7C3/SiC/SiC coated C/SiC composite was investigated in wet air at 700, 900 and 1300 ºC under 1 atm with a gas velocity of 3.0 cm s-1, and compared with that of a SiC/SiC/SiC coated C/SiC composite. The wet oxidation produced phases on the Cr3Si-Cr7C3/SiC/SiC coating were Cr2O3 at 700 and 900 ºC, and Cr2O3 and SiO2 at 1300 ºC. The Cr3Si-Cr7C3/SiC/SiC coating showed enhanced protection against wet oxidation compared to the SiC/SiC/SiC coating. After oxidation for 10 h, the Cr3Si-Cr7C3/SiC/SiC coated composites showed nearly the same failure behavior and residual flexural strength as the as-received composites.

The effects of ethylene-vinyl acetate copolymer (EVA) and dicumyl peroxide (DCP) addition on injection moldability and tensile properties of recycled polyethylene (PE) from disposable drip tapes were studied. DCP showed an adverse impact on the injection moldability of recycled PE materials, while EVA had positive effects on it. Tensile properties of the reproduced PE increased with the increasing amount of EVA up to 10 wt.% and decreased beyond it. The DCP addition reduced the elastic properties of the reproduced PE, while it enhanced the tensile strength. Overall, the co-addition of 6 wt.% EVA + 0.4 wt.% DCP could improve the tensile strength of the reproduced PE materials.