Load-elongation (L-E) curves of undrawn and drawn nylon 6 filaments were plotted on the same abscissa to investigate their drawing behaviors.
1. The elongation at primary yield point of drawn filament was almost same as the drawing ratio of the filament.
2. Drawn filament at slow drawing speed had a higher effective drawing ratio due to higher degree of molecular orientation than that at high speed.
3. When drawn filament was relaxed at a given drawing ratio for various time length, the longer the time of relaxiation, the higher the degree of molecular orientation and the higher the primary yield point shifts according to the longer time length, as if the equivalent higher drawing ratio were applied.

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The previous paper presented a method of the theoretical calculation of biaxial tensile properties of two bar tricot fabrics.
This paper investigates the accuracy of this theory by measuring the tensile properties of some actual fabrics by means of a biaxial tensile tester, and comparing the measured values with the theoretical ones.
The result shows that the fabrics knitted with fine yarn or low-bulkiness yarn provide a very good agreement between the theoretical and experimental results. For the fabrics knitted with thick yarn or high-bulkiness yarn, however, there is some amount of difference in some biaxial-deformation modes between them.
Two improvements have been done on this theory based on those observations : (1) the structure of the unit model is corrected to become closer to actual fabric structure and (2) the compressive deformations of yarns of needle loop and sinker loop are calculated seperately.
These improvements have made the theory more useful for the practical design of almost all kinds of two bar tricot fabrics.

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