The pull-out strength of Z-pins was tested by the single Z-pin pull-out tests from the composite laminates,the critical embedded length has been calculated and tensile strength utilization ratio was introduced to characterize the utilization degree of tensile strength of Z-pins during the pull-out processes.The results show that,the critical embedded depth of the Z-pins with the diameter of 0.50mm and that of 0.28mm are 5.1mm and 3.1mm respectively.And,when the embedded depth is below the critical depth,Z-pins pull-out from the laminates and the pull-out strength of the Z-pins is proportional to the embedded depth,and is inversely proportional to the diameter.When the embedded depth is equal to or greater than the critical depth,breaks occur in the Z-pins,and the tensile strength utilization ratio of Z-pins reaches 100%.Finally,some suggestions for improving tensile strength utilization ratio of Z-pins were put forward.
Key words
Z-pin /
pull-out strength /
composites /
pull-out tests /
tensile strength
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References
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