A Method to Determine Fracture Toughness Using Berkovich Indenter for Bulk Materials

Abstract:

An indentation approach with Berkovich indenter is proposed to determine fracture toughness for ductile materials. With decrease of effective elastic modulus, an approximate linear relationship between logarithmic plastic penetration depth and logarithmic effective elastic modulus, and a quadratic polynomial relationship between the plastic penetration depths and penetration loads are exhibited by indentation investigation with Berkovich indenter. The damage constructive equation of effective elastic modulus is proposed to determine the critical effective elastic modulus at the fracture point, which is the key problem to calculate the indentation energy to fracture. The critical plastic penetration depth is identified after the critical effective elastic modulus can be predicted by conventional mechanical properties. The fracture toughness is calculated according to the equation of penetration load, plastic penetration depth and the critical plastic penetration depth.

• Periodical: Applied Mechanics and Materials (Volume 331)
• Pages: 456-460
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.331.456
• Online since: July 2013
• Authors: Min He, Duan Hu Shi, Feng Yang, Ning Zhang, Hua Feng Guo
• Keywords: Berkovich Indenter, Damage Mechanics, Ductile Materials, Indentation Fracture Technique

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