4 results about "Material constants" patented technology

The invention belongs to the technical field of metal material hot working, and provides a method and system for constructing a thermal deformation constitutive model of a spray-formed 2195 aluminum-lithium alloy, and the method comprises the following steps: obtaining flow stress data according to a hot compression test; correcting the flow stress data to obtain calibrated flow stress data; identifying a peak stress and a material constant according to the calibrated flow stress data, and summarizing a Z parameter expression; introducing a strain influence function according to the material constant, and fitting a strain function; and substituting the strain function into the Z parameter expression to obtain a constitutive model. According to the method, the high-precision constitutive model considering the strain influence is established for the extrusion state spray forming 2195 aluminum lithium alloy for the first time, material parameters under different strains are identified through a system, the applicability of the model in a large deformation forming process is remarkably improved, and the prediction error is lower than 5%; a reliable theoretical tool is provided for formulating a hot working process, the trial and error cost is reduced, and the product quality and the structure uniformity are improved.

The invention discloses a method for determining a low-cycle fatigue life prediction model based on strain rate sensitivity, a prediction method and a related device, and relates to the field of fatigue life prediction of high-temperature structural materials.The method comprises the steps that firstly, a reference strain rate is selected, and a uniaxial tensile test is conducted on a sample component; obtaining net tensile hysteresis energy and low-cycle fatigue life of different strain amplitudes at the reference strain rate; and based on the data, utilizing a classic energy life model to obtain a material constant parameter. And performing a uniaxial tensile test on the sample component to obtain the tensile plastic strain energy density of each strain rate in the strain rate range. And obtaining a change factor of each strain rate based on the tensile plastic strain energy density of each strain rate. And based on each strain rate change factor, the material constant parameter and the classical energy life model, obtaining a corrected energy model of each strain rate. According to the method, the low-cycle fatigue life of the material in a wide strain rate range can be accurately predicted.

To provide a technique for more simply estimating the fracture life of a rubber composition.SOLUTION: A method for estimating a fracture life of a rubber composition includes a step of acquiring a material constant of a test piece of a target rubber composition, a step of acquiring a repeated strain condition or a repeated stress condition, and an estimation step of calculating a crack growth rate of the test piece or a number of times at fracture indicating the number of times of the repeated load at which the test piece fractures, by using the material constant and the strain condition or the repeated stress condition, assuming that the repeated load acts on the test piece of the target rubber composition in a repeated tensile test.SELECTED DRAWING: Figure 1

The present application relates to hydrogen energy transportation and material mechanical property testing technical field, specifically to a kind of high-pressure hydrogen environment hydrogen transportation pipeline material constant load fracture toughness efficient determination method, by precasting the crack depth corresponding to different stress intensity factor level in two compact tension specimens respectively, and using orifice plate to mechanically connect the two, make two specimens simultaneously bear the same constant tensile load in high-pressure hydrogen environment, and after the fracture of any specimen, load can still be stably transmitted to another specimen, so that the crack propagation response data under two different crack depths in single constant load test is simultaneously obtained.The present application effectively utilizes the test time resources, and makes the test efficiency more than doubled.