Coupon validating machine
The proposed model uses a power law in strain hardening range and a weighted power law in the postultimate range.The true stress-true strain model parameters were established through matching of numerical analysis results with the corresponding standard uniaxial tensile test experimental results.
The stress-strain relationship established on the basis of instantaneous deformed dimensions of the test coupon is known as the true stress-true strain relationship (dash line in Figure 1).
In general, the strain softening is associated with the necking range of the test.
Once the specimen begins to neck, the distribution of stresses and strains become complex and the magnitude of such quantities become difficult to establish .
This paper establishes five-stage true stress-true strain models for structural steels, based on numerical simulations calibrated against experimental uniaxial tension test results.
Subsequently, the accuracy of these proposed models was established through comparisons with the experimental uniaxial tension test results associated with tension coupons having a small size central hole.