A Prediction Method of Durable and Instantaneous Limit Mechanical Properties of Polymers

Abstract

The invention is a method for predicting the permanent and instantaneous limit mechanical properties of polymers for the performance evaluation of viscoelastic materials. Including the following steps: condition selection and sample preparation, mechanical test, curve preparation and data prediction. In the selection of conditions and sample preparation, the target is all viscoelastic materials. During the mechanical test, perform stress relaxation test, creep failure test and stress relaxation failure test at a series of temperatures to obtain data such as relaxation modulus and failure time; in the curve preparation and data prediction stage, according to the mechanical test results and prediction goals, make The relaxation modulus-time curve and the relaxation modulus master curve at a series of temperatures can be used to determine the relationship between a set of ultimate mechanical properties and action time, and obtain the predicted value of the permanent and instantaneous fracture strain or fracture strength of the polymer. The invention has the advantages that the method is simple and effective, the data is accurate and reliable, the test operation is convenient, the test process is simplified, and the test conditions are reasonable.

Description

technical field [0001] The invention relates to a technique for evaluating the mechanical properties of viscoelastic materials in extreme states, in particular to a method for predicting the permanent and instantaneous limit mechanical properties of polymers. Background technique [0002] In the prior art, the stress-strain master curve prediction method is usually used, which utilizes the time-temperature equivalent principle of polymer viscoelasticity, uses high temperature to simulate the permanent state, and uses low temperature to simulate the transient state. A series of stress-strain tests with different strain rates at different temperatures are carried out on the material to obtain the ultimate mechanical properties-strain rate curve of the material. Through curve translation, the test curves at different temperatures are overlapped into one curve to form a main limit mechanical properties at the reference temperature. curve. On the main curve of mechanical propert...

AI Technical Summary

Problems solved by technology

The main defects of the main curve prediction method are: affected by the characteristics of the polymer material, the time-temperature equivalent performance of the fracture strain is not ideal; the prediction time scale is too small; the stress-strain test is a destructive test, and the workload is large

Images