DETERMINATION OF FICTITIOUS STRAIN-HARDENING EXPONENT, STRENGTH COEFFICIENT, YIELD STRENGTH AND TENSILE STRENGTH USING CONTINUOUS INDENTATION TEST

摘要

A measurement method of fictitious strain-hardening exponent, strength coefficient, yield strength, and tensile strength using a continuous indentation test is provided to analyze elastic deflection and plastic pile-up as analyzing factors of a contacting area between an indenter and a sample material when testing indentation tensile and yield properties. A measurement method of fictitious strain-hardening exponent, strength coefficient, yield strength, and tensile strength using a continuous indentation test includes the steps of setting an n value of a virtual strain-hardening exponent of a specific austenite metal, estimating a value of f(n) by substituting the set value of n into f(n), estimating a value of (dm)k at a kth indentation test by substituting the estimated value of f(n) into dm(f(n),hf), where k is an integer from 1 to m, estimating a value of nj to allow m number of (dm)k to approach (Lmax)k=lambda(dm)khj+2, comparing the value of nj with the value of n set in the setting step, repeating the step of setting, the step of estimating the value of f(n), the step of estimating the value of (dm)k, the step of estimating the value of nj, and the step of comparing by setting n to as nj when the value of nj is different from the value of n, and determining a final value of nf as nf=nj when the value of nj is equal to the value of n. The value of n is 0.001 when the setting is performed at first time.