An improved analysis of the potential drop method for measuring crack lengths in compact tension specimens

✍ Scribed by Mark E. Orazem; Wolfgang Ruch

• Publisher: Springer Netherlands
• Year: 1986
• Tongue: English
• Weight: 640 KB
• Volume: 31
• Category: Article
• ISSN: 1573-2673
• DOI: 10.1007/bf00044048

✦ Synopsis

A single-parameter logarithmic equation is suggested for the calibration of the potential drop method for measuring crack length in compact tension specimens. This equation follows the correct asymptotic solution for long crack lengths and is shown to hold for even very short crack lengths for specimens with a small notch. Use of this equation provides a first step towards evaluation of calibration data for anomalies such as those associated with variation of electrical conductivity due to plasticity of the crack tip and with uneven crack growth. In addition, use of this equation as a two-parameter model allows determination of the electrical resistivity of the specimen from the calibration data. Data are presented for specimens with large notches which support the results obtained in a previous paper by a numerical method coupled with conformal mapping.