振动时效效果动应力判据的数学建模方法

Modelling Method of Evaluation Criterion of Vibration Stress Relief Effect with Dynamic Stress

为了实现振动时效(VSR)效果的现场定量快速评定,提出了振动时效动应力判据的设想:仅通过动应力参数的测量就可迅速地求得消应力效果。本文采用碳素结构钢焊接试板的VSR模拟试验,通过实验设计、模拟试验、数据处理、回归方程形式设计、回归拟合效果分析…建立了振动时效动应力判据数学建模研究的系统方法。并求得了时效工艺过程残余应力下降量εv与动应力幅度σd、加载次数n和原始残余应力水平k之间的数学模型VSR-DP经验方程:εv=f(σd,n,k)。研究结果证明了振动时效动应力判据在工程应用上的可行性;VSR-DP经验方程可用于碳素结构钢振动时效实际工艺效果的评定。

To quickly and quantitatively evaluate the vibration stress relief (VSR) effect in the site, assumption about VSR criterion is presented. Only according to the dynamic stress value, the effect of stress relief will be calculated. The welded test plates of carbon structure steel were applied to VSR stimulated experiment. A mathematics model and evaluation criterion on VSR with dynamic stress has been established by simulated test, data process, regression equation design and effective analysis of regression fit. And a VSR-DP experience equationεv = f( σ d, n, k ) was acquired, in which the reducing quantity of residual stressεv is relative to dynamic stress value σd, load times n and original residual stress level k etc. The test result has proved that VSR criterion with dynamic stress is useful in engineering application, and VSR-DP experience equation would be applied to evaluate VSR effect of carbon steel structure.