Fiber Properties and ldentification Stress-strain curves Initial modulus The slope of the first section of the stress-strain curve(ratio of the stress to strain) also called Youngs modulus closely follows Hook's Law smaller modulus, easier to elongate under small stresses For different applications, different requirements ordinary apparels: high initial modulus womens sheer hosiery: low initial modulus composites: extremely high initial modulusFiber Properties and Identification • Stress-strain curves – Initial modulus The slope of the first section of the stress-strain curve (ratio of the stress to strain) also called Young’s modulus closely follows Hook’s Law smaller modulus, easier to elongate under small stresses. For different applications, different requirements: ordinary apparels: high initial modulus women’s sheer hosiery: low initial modulus composites: extremely high initial modulus