5 results about "Effective strain" patented technology

The application discloses a method for predicting and evaluating the overall formability and local formability of high-strength steel. u The uniaxial tensile test is carried out, and the strain is uniformly distributed before the material reaches the tensile strength or necking instability, which reflects the overall formability of the material. The effective strain range with the necking as the center is about 20 mm, the thickness-based fracture strain of a sample with a complete fracture is determined as the evaluation index of the local formability. The method can well predict and evaluate the overall formability and local formability of advanced high-strength steel, and has the advantages of simple operation, reliable result, wide application range and low cost.

The invention discloses a low-cycle fatigue life prediction method and system suitable for a directional solidification turbine blade, and relates to the technical field of gas turbine key component life determination, and the method comprises the steps: obtaining to-be-measured data of the directional solidification turbine blade; the data to be measured comprises elastic modulus and low-cycle fatigue performance data; calculating an orientation factor based on the elastic modulus; determining effective strain energy density based on the low-cycle fatigue performance data; and calculating the predicted low-cycle fatigue life of the directionally solidified turbine blade based on the orientation factor and the effective strain energy density. The method can improve the prediction precision of the low-cycle fatigue life of the directional solidification turbine blade.

The invention relates to the technical field of titanium alloy material processing, in particular to a regulation and control method for improving consistency of high-temperature fatigue performance of a titanium alloy forging stock based on effective strain, and the method comprises the following steps: 1) preparing a titanium alloy bar or a cake-shaped forging stock meeting requirements; (2) a finite element simulation technology is adopted, and a single-heating-number or multi-heating-number thermal deformation process is drawn up with the optimization targets that the cumulative effective strain of the core of the forging stock in the diameter direction and the volume fraction of a difficult-to-deform area is smaller than 20%; 3) simulating an optimized thermal deformation process, and performing air cooling after forging; (4) carrying out high-temperature solution treatment, and carrying out water quenching or oil quenching after heat preservation; and 5) carrying out long-time strengthening treatment, and then cooling to room temperature. According to the method, effective strain distribution is quantitatively controlled, a specific heat treatment system is combined, a coarse primary alpha phase is effectively crushed, homogenization of a microscopic structure is achieved, the high-temperature fatigue performance consistency of different positions of the large-size titanium alloy forging stock is remarkably improved, and the method is particularly suitable for blank pretreatment of large disc forgings for aero-engines.

The invention relates to the technical field of strain measurement, in particular to a full-field strain quantitative measurement method based on DIC auxiliary stress luminescence, which comprises the following steps: (1) preparing a stress luminescence film metal test piece; (2) carrying out tensile test and optical acquisition through a measuring system; (3) data extraction and picture processing; (4) establishing a quantitative calibration relationship between the stress luminescence light intensity and the DIC effective strain; finally, the quantitative calibration relation y = 0.25 x + 3.59 of the stress luminescence light intensity and the DIC effective strain is obtained, x represents light intensity data, y represents strain data, a quantitative strain visualization cloud picture of the test piece is drawn, and quantitative full-field strain measurement based on DIC auxiliary stress luminescence can be achieved. According to the method, stress luminescence detection and DIC strain measurement have good compatibility in the aspect of data acquisition and processing, and direct conversion from a stress luminescence intensity field to a physical strain field is realized, so that the method can be popularized and applied to quantitative analysis of mechanical response characteristics of various stress luminescence material systems.

A numerical simulation analysis method for the swelling and bursting of pressurized water reactor fuel rod cladding, relating to the field of reactor safety analysis technology, includes: obtaining constant parameters of the fuel rod cladding; establishing and meshing a geometric model; assigning physical property values ​​to each element mesh; calculating the temperature distribution of the fuel rod cladding and determining whether a phase transition has occurred; if a phase transition has occurred, calculating the phase transition process of the cladding material; if the phase transition is complete or has not occurred, calculating the creep and plastic behavior of the cladding material; updating the effective stress and effective strain rate of the cladding material, and then calculating the yield stress of each element mesh; determining whether both the effective strain rate and yield stress have reached the corresponding failure thresholds; if neither has reached the threshold, repeating the calculation; if either reaches the failure threshold, performing a dynamic bursting process calculation of the cladding until the pressure inside and outside the cladding is balanced, and simulating the dynamic bursting process of the cladding; this method addresses the limitations and inaccurate results of traditional bursting analysis.