(1. 裝甲兵工程學(xué)院 機(jī)械工程系，北京 100072；
2. 陸軍航空兵研究所 信息情報室，北京 101121)
摘 要: 針對Berkovich壓痕提出一個獨立的儀器化壓入響應(yīng)參數(shù)-中邊距與名義中邊距之比d/dn，用于衡量壓痕鼓凸/沉陷程度。基于量綱分析和有限元數(shù)值仿真，建立中邊距與名義中邊距之比d/dn、名義硬度Hn、比功We/Wt與金屬材料彈塑形參數(shù)之間的無量綱函數(shù)關(guān)系式，并以此為基礎(chǔ)建立了基于Berkovich壓痕的金屬材料彈塑形參數(shù)儀器化壓入識別方法。該方法僅利用單一Berkovich壓頭儀器化壓入金屬材料所得載荷-位移曲線及Berkovich壓痕即可確定金屬材料的彈性模量E、應(yīng)變硬化指數(shù)n、條件屈服強度σ0.2及強度極限σb。4種常用金屬結(jié)構(gòu)材料彈塑性參數(shù)的儀器化壓入識別結(jié)果驗證了該方法的有效性。
關(guān)鍵字: 金屬材料；儀器化壓入；壓痕；彈塑性參數(shù)
（1. Department of Mechanical Engineering, Academy of Armored Force Engineering, Beijing 100072, China;
2. Information and Intelligence Unit, Army Aviation Research Institute, Beijing 101121, China）
Abstract:The ratio of the center-to-border distance of Berkovich indentation impression to the nominal center-to-border distance was introduced as an independent instrumented indentation response parameter to describe the extent of pile-up/sink-in around Berkovich indentation impression. Based on the dimensional analysis and finite element simulations, the explicitly dimensionless relationships among three independent instrumented indentation response parameters (the other two parameters extracted from load-depth curve are nominal hardness and the ratio of elastic work to total work) and elastic-plastic properties of metals were established. Further more, a new method based on Berkovich indentation impression was proposed for determining elastic modulus E, strain hardening exponent n, conditional yield strength σ0.2, ultimate strength σb of metals. Finally, the effectiveness of the method was verified by the determination results of four kinds of structural metal.
Key words: metal; instrumented indentation; indentation impression; elastic-plastic properties
