采用新型编织技术制备了螺旋平行分布和交叉分布的4种不同结构的一体化血管覆膜支架,研究支架不同结构与其平面压缩性能的关系,考察不同压缩测试条件(压缩和回复速率以及压缩停滞时间)对支架的径向压缩强力、应力松弛率和弹性回复率的影响,综合评价其压缩性能.结果表明:小节距同向螺旋平行分布血管覆膜支架(A2)具有压缩强力较高、应力松弛率最小、弹性回复率高,故其压缩性能最好;随着压缩停滞时间的延长,大节距同向螺旋平行分布血管覆膜支架(A1)和交叉分布血管覆膜支架(B1和B2)的应力松弛率明显增加,且弹性回复率降低,%Four integrated stent grafts with crossed or parallel spiral nitinol wires were produced by novel braiding technology.The plane compression performance of different stent construction was evaluated.The stent grafts were tested under different conditions(loading and recovery rate and relaxation time),then the radial compression force,stress relaxation ratio and elastic recovery rate were analyzed.The results indicate that the stent graft(A2) which has parallel spiral nitinol wires and pitch length possesses best compression performance.The stent graft A2 shows higher compression force,the lowest stress relaxation ratio and high elastic recovery rate.Prolonging the relaxation time,sample A1,B1 and B2 show significant increase of stress relaxation ratio and decline of elastic recovery.
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