玉米籽粒质构穿刺与原位压缩力学特性研究

目的]探索一种测试玉米籽粒力学性质的新方法,建立一种物料力学研究新方法。方法]对玉米籽粒分别进行传统穿刺试验和原位压缩试验,在不同加载速率(0.02、0.06、0.10 mm/s)及不同含水率(11.37%、13.86%、14.78%、16.13%、18.48%)下对各部位穿刺力学参数进行显著性和变异系数分析。结果]加载速率0.02 mm/s、含水率14.78%的穿刺组试验结果最稳定;稳定组的原位压缩试验的最大破裂力、弹性模量和总功在某些部位与传统穿刺力学参数有较好的相关性,原位压缩破裂力和总功与传统穿刺的部分力学参数间存在极强的相关性。在验证了原位压缩试验可行的基础上,对原位裂纹图像分析可以更清晰地观察裂纹的形貌及扩展。结论]原位压缩测试结果与传统穿刺力学参数间具有较好的相关性,原位压缩测试可代替传统穿刺测试。

Study on Mechanical Properties of In-situ Compression and Texture Compaction of Maize

Objective] To explore a new method for testing the mechanical properties of maize kernels and to establish a new method of material mechanics.Method] Different loading rates (0.02,0.06,0.10 mm/s) and different water content (11.37%,13.86%,14.78%,16.13%,18.48%) were studied,the significance and coefficient of variation of the puncture mechanical parameters were analyzed.Result] The results of the puncture test group with the loading rate of 0.02 mm/s and the water content of 14.78% were the most stable.The maximum bursting force,elastic modulus and total work force of the stability test in the stable group were in some parts with the traditional puncture mechanics parameters.There is a strong correlation between the in situ compression rupture force and the total work force and the partial mechanical parameters of the traditional puncture.On the basis of validating the in-situ compression test,the in-situ crack image analysis can more clearly observe the morphology and expansion of the crack.Conclusion] The in situ compression test results have a good correlation with the traditional puncture mechanics parameters,the in situ compression test can replace the traditional puncture test.