Hill Engineering Blog

Come see us at PS&S 2017

Hill Engineering will be presenting at the upcoming Propulsion Safety & Sustainment Conference (PS&S) in Phoenix, AZ on May 22nd through May 25th. We invite you to come see us. We will be sharing some recent work about experimental validation of process models for nickel engine disk design. Hill Engineering’s presentation will include a summary of residual stress measurements used to calibrate and validate process models for nickel engine disk applications. The abstract text is presented below.

Residual stresses are known to play a significant role in the performance of materials including from a fatigue, fracture, and distortion perspective. Process models have been developed to predict residual stresses from disk manufacturing (e.g., quenching, aging, and machining). These process models provide the necessary inputs to subsequent performance models that forecast the behavior of the material in the presence of residual stress. Calibration and subsequent validation of process models is essential for effective implementation, which relies upon residual stress measurements.

Many methods exist for the measurement of residual stress including: hole drilling, slitting, contour, neutron diffraction, and x-ray diffraction with layer removal. Each of these methods has particular advantages (e.g., repeatability, precision, and measurement depth) and trade-offs (e.g., accuracy versus throughput, measurement depth versus sensitivity). Selection of appropriate measurement methods is critical to obtain residual stress data that suit an intended purpose. An ICME framework using Bayesian updating methods to calibrate a bulk residual stress model was demonstrated under the Air Force funded Metals Affordability Initiative Foundational Engineering Program (FEP). This presentation will present examples of residual stress measurements used to calibrate and validate process models for nickel engine disk applications.

If you are planning to attend the conference please stop by to discuss Hill Engineering’s capabilities in fatigue analysis and design and residual stress measurement. Please contact us for more information.