Trade‐Off Between Internal and External Pressure Performance in 3D Angle‐Interlock Tubular Woven Composites

Internal pressure and localized external loads place competing demands on the structural design of tubular composites. Three‐dimensional angle‐interlock tubular woven composites (3DATWCs) with different warp lining yarn ratios and warp column counts were fabricated from carbon fiber and epoxy resin and evaluated through quasi‐static internal pressure, low‐cycle internal pressure fatigue, lateral compression, and low‐energy multiple and high‐energy single drop‐weight impact tests. A mechanical testing device was used to apply internal pressure within the small‐deformation regime. The results demonstrate that reducing the warp column count from 56 to 42 increased the weft density by 36.4% while also reducing wall thickness. At a warp lining yarn ratio of 5:1, the ultimate stress under internal pressure increased from 74.06 to 128.77 MPa, representing a 73.9% increase. Within the 56‐column series, increasing this ratio from 0:1 to 5:1 increased the fatigue life from 25 to 1645 cycles at 80% of the respective maximum internal pressure in quasi‐static tests. However, peak‐load retention after the third impact was 77.2% for ATWC‐1a and 54.6% for ATWC‐5a, despite nearly identical peak loads during the first impact. Under high‐energy single impact, ATWC‐3a reached an ultimate load of 3.79 kN, 17.3% above ATWC‐0a. These findings demonstrate that selecting an appropriate combination of warp column count and warp lining yarn ratio can balance internal pressure resistance and external load‐bearing capacity, guiding the structural design of lightweight woven composite tubes with different requirements for pressure resistance, fatigue life, and repeated‐impact tolerance.