Developer Tutorial: Analyzing Fatigue Testing Data using JMP Fatigue Modeling

This session is for JMP users who have interest in analyzing fatigue testing data (also known as S-N data). 

Metal fatigue is a major failure cause of engineered structures and devices. Examples include bridges, building frames, airframes, turbine engine blades, chassis, load springs, and stents in medical devices. Engineers and scientists collected and analyzed this S-N data for two hundred years to understand the relationships between stress or strain and cycles to failure of experimental specimens. The analysis of S-N data remained challenging.

Recently, Prof. William Q. Meeker and a team of statisticians and engineers conducted multiple years of research on the subject. Their resulting new methodology respects the nature of censoring in fatigue testing data; unifies the theory of inferring fatigue life distribution and fatigue strength distribution; and establishes robust algorithms to estimate parameters. The analytical results are inputs to other reliability engineering practices to predict the reliability of final structures.

JMP 18 introduces Fatigue Model capabilities to implement the new methodology. It offers twenty-four different models, streamlines the process, provides engineers the convenience to explore the data and find plausible models, and supplies comprehensive ways to extract critical information. Using Fatigue Model, you can:

• Choose one of six S-N curve types together with one of four distributions to assemble a model
• Compare different models, graphically and numerically
• Get detailed information for individual models, such as parameter estimates and their confidence intervals; model diagnostics; distribution profilers for fatigue life and fatigue strength distributions; quantile profilers for the two distributions; and custom estimations of probabilities and quantiles with both Wald and likelihood intervals

The Fatigue Model JMP Developer will explain the methodology and demonstrate how to use JMP to analyze fatigue testing data. The session includes time for Q&A.

This JMP Developer Tutorial covers: Understanding the concepts and relationships between fatigue life distribution and fatigue strength distribution; available S-N curve type choices and their relationships; data format; steps to conduct an analysis; and details for navigating and understanding the report.