Carbon fiber reinforced silicon carbide matrix composites(C/SiC)have emerged as key materials for ther-mal protection systems owing to their high strength-to-weight ratio,high-temperature durability,resis-tance to oxi...Carbon fiber reinforced silicon carbide matrix composites(C/SiC)have emerged as key materials for ther-mal protection systems owing to their high strength-to-weight ratio,high-temperature durability,resis-tance to oxidation,and outstanding reliability.However,manufacturing defects deteriorate the mechani-cal response of these composites under extreme thermal-force coupling conditions,prompting significant research attention.This study demonstrates a customized in situ loading device compatible with syn-chrotron radiation facilities,enabling high spatial and temporal resolution recording of internal material damage evolution and failure behavior under thermal-force coupling conditions.Infrared thermal radia-tion units in a confocal configuration were used to create ultra-high-temperature environments,offering advantages of compactness,rapid heating,and versatility.In situ tensile tests were conducted on C/SiC samples in a nitrogen atmosphere at both room temperature and 1200℃.The high-resolution image data demonstrate various failure phenomena,such as matrix cracking and pore linkage.Image-based fi-nite element simulations indicate that the temperature-dependent variation of the failure mechanism is attributable to thermal residual stresses and defect-induced stress concentrations.This work seamlessly integrates extreme mechanical testing methods with in situ observation techniques,providing a compre-hensive solution for accurately quantifying crack initiation,pore connection,and failure behavior of C/SiC composites.展开更多
基金supported by the National Natural Science Foundation of China(No.52325407)Science and Technology Innovation Plan of Shanghai Science and Technology Commission(No.21511104800).
文摘Carbon fiber reinforced silicon carbide matrix composites(C/SiC)have emerged as key materials for ther-mal protection systems owing to their high strength-to-weight ratio,high-temperature durability,resis-tance to oxidation,and outstanding reliability.However,manufacturing defects deteriorate the mechani-cal response of these composites under extreme thermal-force coupling conditions,prompting significant research attention.This study demonstrates a customized in situ loading device compatible with syn-chrotron radiation facilities,enabling high spatial and temporal resolution recording of internal material damage evolution and failure behavior under thermal-force coupling conditions.Infrared thermal radia-tion units in a confocal configuration were used to create ultra-high-temperature environments,offering advantages of compactness,rapid heating,and versatility.In situ tensile tests were conducted on C/SiC samples in a nitrogen atmosphere at both room temperature and 1200℃.The high-resolution image data demonstrate various failure phenomena,such as matrix cracking and pore linkage.Image-based fi-nite element simulations indicate that the temperature-dependent variation of the failure mechanism is attributable to thermal residual stresses and defect-induced stress concentrations.This work seamlessly integrates extreme mechanical testing methods with in situ observation techniques,providing a compre-hensive solution for accurately quantifying crack initiation,pore connection,and failure behavior of C/SiC composites.
