试样厚度对小冲杆试验力与材料强度相关性的影响

Influence of sample thickness on the correlation between force of small punch test and material strength

为了研究试样厚度对小冲杆试验力与材料强度相关性的影响,针对不同厚度(0.1~0.5 mm)的小冲杆试样,使用无屈服平台的虚拟材料进行了有限元模拟。通过提取并分析有限元模拟结果中固定挠度下的小冲杆试验力,证明了小冲杆试验力与材料屈服强度和抗拉强度的双线性关系,且厚度的变化不会影响该相关关系的皮尔逊相关系数。随机生成了屈强比在0.55~0.9之间,屈服强度在200~1000 MPa之间的100种虚拟材料,并通过有限元模拟获得了大量数据,进而采用退火粒子群算法得出了固定挠度下小冲杆试验力和材料强度的关联系数。采用4种真实材料验证了小冲杆试验力与材料强度呈双线性关系的结论。

In order to study the effect of sample thickness on the correlation between the force of small punch test and material strength,finite element simulation was conducted using virtual materials without yield platform for small punch samples with different thicknesses(0.1~0.5 mm).By extracting and analyzing the force of small punch test at fixed deflection in the finite element simulation results,the bilinear relationship between the force of small punch test and material yield strength and tensile strength was proved,and the change in thickness would not affect the Pearson correlation coefficient of the correlation.100 virtual materials with yield ratio between 0.55 and 0.9,and yield strength between 200 MPa and 1000 MPa were randomly generated,and a lot of date was obtained by finite element simulation,then the correlation coefficient between the small punch test force and material strength at fixed defection was obtained by annealing particle swarm algorithm.Finally,the bilinear correlation between the small punch test force and material strength was verified by using four actual materials.