Abstract: The bra strap was taken as the object in this paper. Taking the characteristics of the strap and its application in daily use into account, the tensile failure test and specified elongation repeatedly tensile experiments were adopted to test the main mechanical performances and tensile properties of the strap samples. On the basis of the feature of stretch curve of the straps and the Meredith method to determine the yield point of fibre, the method of determing the effective elastic point of the strap was discussed. The paired sample test was used to detect the significant difference between the first and fifth stretched elastic recovery as well as plastic strain. The test result suggested that the stretched elastic recovery of the straps would decrease, while the plastic strain would increase in the daily use. The analysis of variance and covariance were used to discuss the effects of the elongation on elastic recovery and plastic strain of the straps. The result indicated that the elongation of the bra straps in daily use had no significant effect on both tensile properties discussed above.

Key words: bra strap, mechanical property, effective elastic point, paired sample test, analysis of variance