Instron^® Bluehill^® Fracture version 2.7

Bluehill Fracture includes automated slope determination in accordance with ASTM E3076 – the methodology is explicitly recommended within ASTM E399 for “brittle” linear-elastic plane strain fracture toughness (K_Ic). Instron is the only global manufacturer to have participated in pre-publication development of E3076 and implemented it immediately in fracture toughness software at first release. A recent round-robin project, with analysts from multiple laboratories using a range of software tools, showed that incorporating the E3076 methodology can reduce variability in analysis results (of identical data), by up to a factor of 10.

Bluehill Fracture software automatically installs a number of example test files and methods. These are primarily intended as an educational tool for the user, to explore method setup and what typical results may look like, before they start running their own tests. For ASTM E1820, a number of data sets are published as an adjunct to the standard, with expected analysis results, to assist in validation of analysis tools. The installation also includes these data converted into Bluehill Fracture file format, to provide simple evidence of verification of J_Ic analysis.

Bluehill Fracture continues to support analysis of K_Ic, CTOD_c, and J_c, according to BS7448-1:1991, but this standard is now withdrawn and superseded by BS EN ISO 12135:2021.

In 2022 a corrigendum to ISO 12135:2021 was published which changed the formulae to calculate CTOD, because a symbol was completely missing from the original 2021 publication. This leads to a significant difference in the returned value.