Hill Engineering Blog

Hill Engineering introduces ExpressRS

For materials engineers, designers, and managers seeking residual stress measurements, Hill Engineering is a trusted source for a broad range of best-in-class measurement capabilities. But while we always strive to deliver quality results in a timely manner, sometimes a job requires a faster than normal turn-around. This is why we’ve introduced ExpressRSTM, a service geared toward expedited delivery of residual stress measurement results. Continue reading Hill Engineering introduces ExpressRS

Additive Manufacturing Benchmark Test Series

As a follow-up to our previous post about additive manufacturing (AM) we wanted to highlight some other activities in the additive manufacturing space.

One such activity that Hill Engineering has been involved in is the NIST AM-Bench program. AM-Bench is developing a continuing series of controlled benchmark tests with two initial goals: 1) to allow modelers to test their simulations against rigorous, highly controlled additive manufacturing benchmark test data, and 2) to encourage additive manufacturing practitioners to develop novel mitigation strategies for challenging build scenarios. As part of this program, Hill Engineering has been working in collaboration with UC Davis to support residual stress measurement activities using the contour method. Continue reading Additive Manufacturing Benchmark Test Series

Case Study Highlight: 3D Scanner

Hill Engineering recently installed a Nikon ModelMaker H120 3D scanner, which is proving to be very useful in our laboratory. In addition to scanning services we now offer to outside parties, we’ve also implemented this technology into our residual stress measurement processes. This new capability allows us to produce faster, more accurate results than ever before. Continue reading Case Study Highlight: 3D Scanner

BAMF webinar

Hill Engineering will be participating in an upcoming webinar related to 3D fatigue analysis using our Broad Application for Modeling Failure (BAMF) software. BAMF is a software tool for predicting the growth of fatigue cracks in 3D parts. Starting from an assumed initial flaw, BAMF combines stress and crack growth analyses to predict the evolution of crack shape and size in 3D. BAMF provides a robust and automated link between two leading tools: AFGROW and StressCheck™. Continue reading BAMF webinar

Residual stress biaxial mapping validation

Hill Engineering recently published new research detailing our efforts to validate the PSR biaxial mapping technique for residual stress measurement.

This new technique generates two-dimensional maps of additional residual stress components over the same plane as the original contour method measurement. The paper is titled Assessment of Primary Slice Release Residual Stress Mapping in a Range of Specimen Types and appears in the November 2018 volume of Experimental Mechanics. Continue reading Residual stress biaxial mapping validation

2019 SEM Annual Conference and Exposition on Experimental and Applied Mechanics

Hill Engineering will be presenting at the upcoming SEM Annual Conference and Exposition on Experimental and Applied Mechanics in Reno, NV from June 3rd through June 6th. We invite you to come see us. This conference focuses on all areas of research and applications pertaining to experimental mechanics, and has evolved to encompass the latest technologies supporting:

  • optical methods
  • additive & advanced manufacturing
  • dynamic behavior of materials
  • biological systems
  • micro-and nano mechanics
  • fatigue and fracture
  • composite and multifunctional materials
  • residual stress
  • inverse problem methodologies
  • thermomechanics
  • time dependent materials.

Hill Engineering’s presentation will include a summary of recent work related to regularization uncertainty in slitting residual stress measurement. The abstract text is presented below.

This presentation describes the development of an uncertainty estimate for slitting residual stress measurement. The uncertainty estimate includes a newly developed uncertainty estimate related to the smoothing used in the stress calculation procedure called the regularization uncertainty. This work describes the approach to define the regularization uncertainty, shows the usefulness of the uncertainty estimate in a numerical experiment and a repeatability study. The uncertainty estimate is shown to meet an acceptance criterion that compares the calculated (measured) stress ± its uncertainty estimate to the true value for the numerical experiment or the mean stress from the repeatability study. This works shows the regularization uncertainty estimate to be a necessary contributor to the uncertainty in slitting and additionally the uncertainty estimate developed here reasonably predicts the uncertainty present in slitting method residual stress measurements.

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.

Meet our new 3D scanner

We at Hill Engineering are always looking for ways to improve the accuracy and efficiency of our laboratory. That’s why we recently acquired a 3D scanner for our laboratory, which will aid in many aspects of our residual stress measurement processes, as well as enable us to provide further services to our customers. In the newest video on our YouTube channel , we discuss some of the highlights of this tool. Continue reading Meet our new 3D scanner

Residual stress in additive manufacturing

Additive manufacturing (AM) is a manufacturing process that deposits material in a controlled manner to build three-dimensional part geometry (bit by bit). This is in contrast to traditional manufacturing processes where material is cut or removed (i.e., subtracted) from the raw stock to create the intended part shape. The potential for additive manufacturing to significantly improve the economics and performance of manufactured parts for certain applications has made it a popular topic. However, since most additive manufacturing processes are highly thermal (e.g., material is deposited in a melted form and solidifies into the desired shape) significant residual stresses can develop. Hill Engineering has been working with many collaborators to better understand the influence of these processes on residual stress. Continue reading Residual stress in additive manufacturing