(裝甲兵工程學(xué)院 機(jī)械工程系，北京 100072)
摘 要: 采用有限元數(shù)值仿真結(jié)合儀器化壓入實(shí)驗(yàn)的方法，選擇Vickers壓頭和面角為172°的四棱錐壓頭用于金屬材料塑性參數(shù)的儀器化識(shí)別，通過量綱分析和有限元數(shù)值仿真建立基于壓入比功We/Wt的金屬材料塑性參數(shù)儀器化壓入識(shí)別方法和基于名義硬度Hn的金屬材料塑性參數(shù)儀器化壓入識(shí)別方法。根據(jù)識(shí)別方法的精度分析結(jié)果，確定條件屈服強(qiáng)度σ0.2和應(yīng)變硬化指數(shù)n作為金屬材料塑性參數(shù)識(shí)別的目標(biāo)參數(shù)。6061鋁合金、S45C碳鋼、SS316不銹鋼、SS304不銹鋼和黃銅5種金屬材料條件屈服強(qiáng)度σ0.2的識(shí)別誤差為-17.5%~4%，基本滿足工程需要，驗(yàn)證本研究中建立的金屬材料塑性參數(shù)儀器化壓入識(shí)別方法的有效性。
關(guān)鍵字: 塑性；儀器化壓入；屈服強(qiáng)度；應(yīng)變硬化指數(shù)；特征應(yīng)力；特征應(yīng)變
（Department of Mechanical Engineering, Academy of Armored Force Engineering, Beijing 100072, China）
Abstract:The instrumented indentation is a useful tool to probe the plastic properties of metals. The finite element computations combined with instrumented indentation experiments were applied to choose the diamond indenters which were used to estimate the plastic properties of metals. The methods for determining the plastic properties of metals based on the ratio of indentation work We/Wt and nominal hardness Hn were established with the aid of dimensional analysis and finite element computations. 0.2% yield strength (σ0.2) and strain hardening exponent (Hn) were suggested to be the target parameters based on the accuracy analysis of the methods. The errors of σ0.2 of 6061 aluminum alloy, S45C carbon steel, SS316 stainless steel, SS304 stainless steel and brass are from -17.5% to 4%, which satisfies the need of engineering application. This verifies the effectiveness of the methods.
Key words: plastic properties; instrumented indentation; yield strength; strain hardening exponent; representative stress; representative strain
