Tests and Numerical Analyses of the Composite Casing Containment Under Hydrothermal Environment

To obtain the inclusion characteristics of carbon fiber resin matrix composite casing in service environment, 2 high-speed impact ballistic tests were conducted before and after hygrothermal treatment, and the corresponding simulation model for the casing hygroscopicity partition hygrothermal test simulation model along with the finite element high-speed impact numerical simulation-analysis model, was established. The results show that, the hygrothermal treatment has significant effects on the impact resistance and energy absorption capacity of the carbon fiber resin matrix composite casing. Under the high-speed impact, the impact resistance and energy absorption capacity of the casing without hygrothermal treatment are better than those of the casing with hygrothermal treatment. The damage form of the casing under high-speed impact is dominated by the tensile failure of fiber and matrix, accompanied by a certain amount of fiber crush and in-plane shear failure, with little or no compression failure observed. The damage occurs in the vicinity of the impact area, and extends along the axial and circumferential direction of the casing. In addition, the tensile failure area of the matrix of the hygrothermally treated layer is significantly larger than that of the matrix of the untreated layer, which verifies the degradation of the mechanical properties of the matrix after hygrothermal treatment.