The first contour method measurement specimen

Hill Engineering’s new facility in Rancho Cordova, CA features a combination of laboratory, research and development, and office space. Our primary conference room is named in honor of Mike Prime, the inventor of the contour method. The Prime Room stands as a tribute to the creativity, insights, and support that Mike Prime has provided to Hill Engineering over the years. One of our favorite pieces on display in the Prime Room is one half of the specimen that was used for the first successful contour method measurement. Continue reading The first contour method measurement specimen

Ring core

At Hill Engineering we work with residual stress on a daily basis. Ring Core is one of the techniques that we use for residual stress measurement. Ring Core is capable of measuring residual stress over depths spanning the near-surface to bulk regions, and can be applied to quantify the average residual stress over the depth of a drilled core. Ring Core is portable, and can be applied under a variety of circumstances, including in the field. Hill Engineering uses Ring Core measurements to support process development and quality control. Ring Core measurements can be performed in our laboratory or at your site, to your specifications. Continue reading Ring core

Hole Drilling Method for Measuring Residual Stresses

We’d like to share with our loyal followers a new book: Hole Drilling Method for Measuring Residual Stresses, written by Gary S. Schajer and Philip S. Whitehead. As you all know, Hole Drilling measures near-surface residual stress. The Hole Drilling method can be applied to quantify the average residual stress over the depth of a drilled hole (typically 1.0 mm depth). It can also be applied to determine the distribution of residual stress versus depth from the surface to a depth of half the hole diameter. Hole Drilling is portable and is a common method for residual stress measurement that can be applied under a variety of circumstances, including in the field. Continue reading Hole Drilling Method for Measuring Residual Stresses

Case Study: Contour Method Repeatability

Recently, Hill Engineering posted a new case study detailing our research into contour method repeatability. In the case study, we performed contour method measurements on multiple similar specimens belonging to six different specimen types: aluminum T-section, stainless steel plate with dissimilar metal slot-filled weld, stainless steel forging, titanium plate with electron beam slot-filled weld, nickel disk forging, and aluminum plate. Continue reading Case Study: Contour Method Repeatability

Residual stress definition

Residual stress definition – residual stress is defined as the stress that is present in a material in the absence of externally applied loading. Residual stresses often form during manufacturing and are typically an unintentional byproduct of a manufacturing process. As engineers we care about residual stresses because they affect material performance. Continue reading Residual stress definition

Mike Prime: a history of the contour method

Hill Engineering has proudly named the primary conference room in our new facility the Prime Room, a tribute to special Hill Engineering collaborator and inventor of the contour method, Mike Prime. We were recently honored to have Mike stop by for a ribbon cutting ceremony celebrating the opening of the Prime Room. In addition to the ceremony, Mike also gave a presentation about the history of the contour method and how it almost didn’t happen. Click on the video below to view Mike’s presentation and see how the contour method grew from one man’s curiosity to what it is today. Continue reading Mike Prime: a history of the contour method

Prime Room Ribbon Cutting

Hill Engineering’s new facility in Rancho Cordova, CA features a combination of laboratory, research and development, and office space. We have proudly named the primary conference room in our facility the Prime Room, a fitting tribute to a special Hill Engineering collaborator, the inventor of the contour method, and inspirational figure, Mike Prime. We were recently honored to have Mike Prime stop by for a ribbon cutting ceremony celebrating the opening of the Prime Room. Continue reading Prime Room Ribbon Cutting

Happy birthday to the contour method

Today marks a major milestone in the field of residual stress measurement. The contour method, one of the most useful and advanced residual stress measurement techniques, was first successfully implemented on this date (August 16th) in 1999 by Mike Prime at Los Alamos National Laboratory. The most significant feature of the contour method is its ability to generate detailed two-dimensional residual stress maps like the one shown below. Please join us in wishing the contour method a very happy 18th birthday! Continue reading Happy birthday to the contour method

Residual stress calculation

In a recent blog post we discussed the question: what is residual stress. As a follow-up, today we are addressing the topic of residual stress calculation. Once you understand the concept of residual stress and are ready to account for its effect on material performance it’s important to quantify the residual stress that is present in your material. Residual stress calculation can include a variety of different topics. Continue reading Residual stress calculation

SEM Annual Conference and Exposition on Experimental and Applied Mechanics

Hill Engineering will be presenting at the upcoming Annual 2017 Conference and Exposition on Experimental and Applied Mechanics, which is organized by the Society of Experimental Mechanics (SEM). The conference will run from June 12, 2017 through June 15, 2017 and will be located in Indianapolis, IN. We invite you to come see us while we share some recent work about residual stress measurement repeatability using the contour method. The abstract text is presented below. Continue reading SEM Annual Conference and Exposition on Experimental and Applied Mechanics