Investigating the Feasibility of Interpolating Scatter in Material Property Data. Case Study: S-N Curves for Ti-6Al4V

摘要

When testing for material properties, the cost and time of the tests are an important factor. It is not practical to test every possible combination of expected environmental and loading scenarios. Therefore, a set of limited data is collected based on certain predetermined load levels and environmental conditions. When dealing with traditional design practices, which rely on safety factors and deterministic analysis, only the trends in material constitutive behavior and strength are captured and interpolated at conditions where there are no physical tests. However, in a non-deterministic design philosophy the scatter in data at the test conditions needs to be characterized accurately and this information needs to be interpolated at conditions where there are no physical tests. The objective of this paper is to communicate the challenges involved with capturing the statistical content of a material system operating in combined extreme environments. In this paper, S-N curves for Ti-6Al-4V are used as a case study to demonstrate the challenge and also investigate some interpolation schemes and their capabilities.