(中國工程物理研究院 總體工程研究所，綿陽 621900)
摘 要: 通過軸對稱缺口圓柱試件設(shè)計，消除了端面摩擦對金屬(特別是延性金屬)試件壓縮變形行為的影響。基于壓縮過程中外力功與試件內(nèi)能之間的能量守恒原理，推導(dǎo)了壓縮流動應(yīng)力的近似修正公式，并給出了相應(yīng)的迭代修正過程。針對鋁合金2024，利用修正后的流動應(yīng)力-應(yīng)變關(guān)系對壓縮過程中試件的最小橫截面直徑和內(nèi)能進(jìn)行了預(yù)測，并與實驗結(jié)果進(jìn)行了比較。研究結(jié)果表明：在整個壓縮過程中，試件的最小橫截面直徑的預(yù)測值與實驗值吻合，且試件內(nèi)能與實驗外力功始終保持一致，從而驗證了該修正方法的有效性。
關(guān)鍵字: 流動應(yīng)力；端面摩擦；缺口圓柱試件；能量守恒；迭代修正
（Institute of Systems Engineering, China Academy of Engineering Physics, Mianyang 621900, China）
Abstract:The influence of interfacial friction on the compressive deformation behavior of metals (especially ductile metals) was eliminated by design of axisymmetric notched cylindrical specimen. Based on the energy conservation between external work and internal energy of specimen in compression test, an approximate correction formula of compression flow stress was derived and the corresponding iterative correction procedure was proposed. For aluminum alloy 2024, both the diameter of minimum cross-section and the internal energy of specimen in compression process were predicted by the corrected flow stress-strain relationships and compared with the experimental results. The results show that the predicted diameters of minimum cross-section are agree with the experimental data and the internal energy of specimen is always consistent with the experimental external work in the whole compression process, which verify the effectiveness of the correction method.
Key words: flow stress; interfacial friction; notched cylindrical specimen; energy conservation; iterative correction
