New Method for Measuring Percentage Elongation after Fracture-Analytical Method

It is specified to use direct measuring method and position transferring method for the measurement of percentage elongation after fracture in GB/T 228-2002. The value of elongation measured by direct measuring method would vary from the location of the broken, and it was not characterized as the only one. Although position transferring method was a remedy for the above method, it was very complicated. The analytical method was proposed to take use of symmetry of elongation deformation from both sides of the broken, and based on the character of which the elongation deformation from the half of the longer part after breaking had covered all the information of elongation, and tensile specimen was invented of which the elongation deformation from both sides of the broken was symmetric. Then the required elongation would be calculated by the way of conversion formula of elongation of GB/T 17600-1998. The result from the analytical method was better than that of the direct measuring method and position transferring method. The analytical method was specially applied to research of percentage elongation after fracture of material.