Digital Commons Network^™

Adaptation Of Shot Peen Parameters For Gear Geometry, David J. Breuer, Beth Matlock

15th International Conference on Shot Peening

Shot peening is a well established process for the surface enhancement of gearing. Gearing is a primary example of a high cycle fatigue application that can benefit from residual stress enhancement. Designing shot peening parameters to specific gear geometry based on material, heat treatment, and surface finish is a more precise way to achieve better performance outcomes. One of the best tools to assist in the optimal shot peening is x-ray diffraction (XRD) and its ability to measure small differences that can result in significant performance outcomes. XRD residual stress measurements are a direct measurement of elastic strain. The diffraction …

Investigations On The Fatigue Strength Of Threads Produced By Different Fabrication Techniques, Philippe Du Maire, Jürgen Hoffmeister, Andreas Öchsner, Michael Johlitz

15th International Conference on Shot Peening

The increasing importance of sustainability in engineering demands the development of long-lasting, high-performance components that reduce material and energy consumption over time. This study investigates how different thread manufacturing processes, i.e., cutting, rolling, and deep rolling, affect the fatigue strength of bolts made from 42CrMo4+QT steel. Cylindrical specimens with M12 threads were subjected to cyclic tensile loading with constant mean stress. Fatigue strength was evaluated using the staircase method, and supporting analyses included X-ray diffraction for residual stress, and full width half maximum examination and Vickers microhardness measurements. Results show that thread rolling significantly improves fatigue strength, achieving 113.8 MPa …

Numerical Assessment Of Shot Peening Contribution To The Fatigue Strength Of Gear Tooth Root, Gurutz Cortabitarte Laucirica, Xuban Telleria, Iñigo Llavori, Ibai Ulacia, Miren Larrañaga, Jon Ander Esnaola

15th International Conference on Shot Peening

Gears are commonly treated with shot peening (SP) and/or case hardening to enhance fatigue resistance. However, their effects are often conservatively assessed using standardized methods, which can limit their optimal application in industrial components. Particularly, the effect of SP over case-hardened gears remains insufficiently explored. Therefore, the present study evaluates the contribution of SP on single tooth bending fatigue (STBF) strength of raw and case-hardened spur gears, commonly used in automotive and heavy machinery industries. In the study four conditions are addressed: (i) untreated, (ii) case-hardened, (iii) shot-peened, and (iv) case-hardened and shot-peened. First, the residual stress field of the …

Effect Of Fine Particle Peening Induced Material Transfer On The Initial Deposition Behavior Of Nickel Electroplating On Aluminum Substrate, Kazuki Iijima, Yutaka Kameyama, Hideaki Sato, Shuhei Kodama

15th International Conference on Shot Peening

Plating on aluminum requires a complex zincate pretreatment. Fine Particle Peening (FPP), using particles ≤200 µm, has gained attention as an alternative due to its ability to transfer particle components onto the surface, potentially improving deposition and adhesion. Previous studies showed enhanced plating on aluminum treated with steel particles. This study investigates the effectiveness of FPP as a pretreatment for nickel electroplating by examining initial deposition behavior. A1050-H24 aluminum was treated using FPP with either steel or glass particles, compared to an untreated specimen. Steel particle FPP created a lamellar microstructure with alternating iron and aluminum phases. EBSD revealed that …

The Effect Of Surface Treatment On The Fatigue Strength Of Sus316l Additive Manufactured Products, Hitoshi Nishijima, Yuji Kobayashi, Toshiya Tsuji, Kiyotaka Masaki

15th International Conference on Shot Peening

Rotating bending fatigue tests were conducted to investigate the effect of shot peening and barrel finishing on fatigue properties of SUS316L made by laser PBF which was one of additive manufacturing processes. Surface roughness, residual stress, and fatigue strength were investigated for each specimen. As a result, the fatigue strength of the barrel finished specimens was almost same or better than that of the shot peened specimens. Barrel finished specimens increased 4.1 times higher fatigue strength than as-built specimens. The surface roughness of the specimens after barrel finishing was reduced by up to 96% compared to the as-built specimens. On …

Enhancing The Fatigue Strength Of Am Materials Via Mechanical Surface Treatment, Fabian Keil, Jan Schubnell, Sascha Fliegener, Alexander Heiss

15th International Conference on Shot Peening

Additive manufacturing (AM) processes, while enabling the production of intricate geometries, frequently result in suboptimal surface quality, which can significantly restrict the fatigue strength of components when compared to those manufactured using traditional methods. This study explores the effectiveness of mechanical surface treatment (MST) techniques, specifically shot peening and deep rolling, in enhancing the fatigue performance of additively manufactured AlSi10Mg and 316L alloys. A combination of experimental investigations and finite element simulations was employed to evaluate the influence of these treatments on surface integrity, microstructure, and fatigue life. The results reveal that both MST approaches lead to substantial improvements in …

Dynamic Flowsheet Modeling Of Shot Peening Processes, Langdon Feltner, Paul Mort

15th International Conference on Shot Peening

Process flowsheet modeling is used to map and predict performance by integrating sub-models within a system. This paper presents a dynamic flowsheet for shot peening used to track the effects of media characteristics, removal of worn media, and replenishment thereof. Input parameters include media characteristics, media feed rate, velocity (i.e., air pressure), effective impact area (i.e., nozzle setup), and recharge replenishment. The media working mix is described dynamically using tri-modal size and shape characteristics: as-manufactured, conditioned, and worn modes, each having impact-dependent rate coefficients for transition to the next mode, i.e., as-manufactured > conditioned > worn > debris. The flowsheet includes the effect …

Expansion Of Laser Peening Application With A High-Power Microchip Laser On A Robotic Arm, Yuji Sano, Yoshio Mizuta, Satoshi Tamaki, Tomonao Hosokai, Tomoharu Kato, Yoshihiro Sakino, Volker Schneidau, Sebastian Holz, Jörg Behler

15th International Conference on Shot Peening

Laser peening (LP) introduces compressive residual stress (RS) onto the surface of metallic materials using nanosecond laser pulses irradiated through a water layer, thereby effectively suppressing fatigue crack initiation. However, conventional LP systems require large, stationary setups, restricting their use to indoor environments. To overcome this limitation, a portable LP device featuring a finger-sized microchip laser mounted on a collaborative robot arm has been developed. Equipped with a compact power supply and a water circulation/recovery system, the device can operate on-site with minimal setup. Successful processing across various materials has confirmed both compressive RS induction and fatigue life extension. Notably, …

Effects Of Laser Peening On Fatigue Properties Of Welded Aluminum Thin Plates, Kiyotaka Masaki, Yoshio Mizuta, Satoshi Tamaki, Yuji Sano

15th International Conference on Shot Peening

To improve the fatigue properties of welded aluminum alloy thin plates used in transportation machinery, handheld laser peening (HH-LP) was applied to 2 mm-thick A5083-O specimens prepared by bead-on TIG welding. Conventional laser peening often causes warping in thin plates, but the HH-LP treatment using low-energy laser pulses avoids this problem. The HH-LP treatment introduced compressive residual stresses of over 200 MPa on the heat-affected zone (HAZ) of the welded specimens. Fatigue tests under plane bending conditions revealed that the HH-LP treatment significantly improved the fatigue strength of the welded specimens, achieving a level comparable to that of the base …

Origin And Interpretation Of Psi-Splitting And Out Of Plane Shear Stress When Using Diffraction Techniques, Mohammed Belassel, James A. Pineault, Michael E. Brauss

15th International Conference on Shot Peening

Psi-splitting is a phenomenon often observed in interplanar d-spacing vs. sin²ψ plots during the analysis of residual stress measurement data when employing the X-ray diffraction (XRD) method. Deviations from the expected linear relationship between interplanar d-spacing and sin²ψ are typically caused by the presence of out-of-plane shear stresses or inhomogeneous stress distributions within the measured phase of the material. In such cases, the d-spacing values measured at different ψ tilt angles deviate from the anticipated linear trend, resulting in a characteristic splitting of the d-spacing vs. sin²ψ plot data, where the shape of the data in the plot takes the …

Evaluation Of Peening Intensity With Nozzle-Mounted Sensor During Processing, Akinori Matsui, Shuji Hayashida, Yuji Kobayashi

15th International Conference on Shot Peening

In recent years, digital technologies have been increasingly applied in manufacturing, including visualization and anomaly detection in production equipment. In shot peening, Peening Intensity is a key process control indicator, but its measurement requires significant manual effort. This study aims to evaluate the possibility of using an AE-sensor-mounted nozzle to estimate Peening Intensity. We conducted experiments comparing sensor outputs with experimented Intensity under controlled conditions. A strong correlation (R² ≥ 0.95) was observed, suggesting that Peening Intensity can be estimated via AE sensing. This approach may contribute to labor-saving and automation in shot peening processes.

Comparison Of Anti-Fouling Performance Of Textured Glass Surface Fabricated By Ductile-Mode Peening And Precision Grinding, Hayato Tagaya, Yutaka Kameyama, Shuhei Kodama, Hideaki Sato, Kento Shinagawa, Ayumu Sekiguchi, Seiji Hirai, Hitoshi Ohmori

15th International Conference on Shot Peening

Recently, there has been a growing demand for precision processing glass. In addition to dimensional accuracy, surface texturing to impart functional properties has attracted increasing attention. For example, anti-fouling performance against powder adhesion is required for cover glasses of solar cells. Powder adhesion is governed by van der Waals forces, which depend on the surface texture of the substrate, suggesting that surface structures influence adhesion behavior. Our previous study demonstrated that angled fine particle peening (FPP) could fabricate a nanoscale fine texture on glass surfaces through ductile-mode peening—glass processing without brittle fracture. In this study, the effect of surface texturing …

Evaluating The Effectiveness Of Localized Masking To Prevent Changes In Residual Stress When Shot Peening, James R. Harrison, James Pineault, Tom Mills

15th International Conference on Shot Peening

When shot peening components, it is common practice to mask certain localized regions where peening roughness is not desirable. For example, surfaces that have been highly machined such as bearing races or areas of interference-fit may require masking to protect them from the cold working effects of shot peening. Oftentimes shot peening the grip sections of fatigue test coupons can prevent cracking and failures due to fretting fatigue in the grip area but could affect the outcome of the test if applied to the gauge section of the coupons. Thus, maintaining an “as machined” surface roughness is the most common …

The Use Of A Dynamic Imaging System To Characterize Particle Size And Shape For Shot Peening Media, Matthew Spink, Tod Canty, Langdon Feltner, Paul Mort

15th International Conference on Shot Peening

Shot peening is a cold working process that enhances the mechanical properties of components such as springs, axles, and gears. Shot media are projected at a high velocity against the material’s surface, creating a layer of compressive residual stress that improves fatigue and wear resistance of the material. The size and shape of the media affect the residual stress layer that is created. To ensure consistent quality, it is critical to characterize and control the particle size and shape distribution of the shot media, both as-manufactured and in the working mix. This paper presents how the use of a dynamic …

Microstructural Changes And Residual Stress Generation On The Periodically Patterned Surface Texture Fabricated By Angled Fine Particle Peening, Yutaka Kameyama, Hideaki Sato, Ryokichi Shimpo

15th International Conference on Shot Peening

Focusing on the potential of peening technology as a surface texturing technique, angled fine particle peening (angled-FPP) has been proposed to fabricate a specific periodical surface structure, which possibly provides various surface functions. It is necessary to further characterize the textured surface to earn more advantages from angled-FPP. Thus, in this paper, texture formation phenomena, residual stress, and microstructural changes were investigated on the angled-FPP specimens.

Methodologies And Applications Of Precision Shot Peening To Hole Or Slot Geometry, James C. Hoffman

15th International Conference on Shot Peening

Shot peening, a commonly used method of fatigue and surface enhancement, is a critical process in many of the components in the aerospace industry. When it comes to small holes and/or slot geometries in these components, the process can become a challenge when these features are smaller than a conventional size Almen strip. In these cases, a decision must be made about how to process this type of geometry. Oftentimes, the method to apply the shot peen process is already defined in a process specification or part print so we must adhere to that method. If a method is not …

Portable Inspection Technology For Shot Peening As Preventive Maintenance At Steel Bridges, Yoshihiro Watanabe, Ryosuke Watanabe, Mitsuru Handa, Kanehisa Hattori, Masato Yamawaki, Koji Kinoshita

15th International Conference on Shot Peening

Positron annihilation lifetime spectroscopy (PALS) is a non-destructively technique to study open-volume lattice defects such as vacancies or dislocations, which is used for fatigue, aging and shot peening inspection. In this study, we developed a portable PALS apparatus that has the ability for on-site measurement[1,2]. We developed the light-shielding technique which enable us to do on-site measurement. Furthermore, we downsized the apparatus size using Monte Carlo simulation technique. We validated that the developed portable apparatus has the same measurement capabilities as the conventional system[1]. We concluded that the developed portable apparatus is sufficiently able to capture the change caused by …

The E-Strip® As A Tool For Predictive Maintenance To Monitor And Control Shot Peening Processes, Walter A. Beach, Scott Glasier

15th International Conference on Shot Peening

The primary objective of this paper is to demonstrate the E-Strip® is capable of providing real-time feedback to the machine controller for making necessary process adjustments due to external forces, such as machine wear. Adjustments may include regulating air pressure and shot flow within pre-defined tolerances dictated by specification. It is anticipated that this integrated approach will significantly reduce variations in intensity levels observed from part to part and lot to lot.

Roughness Parameters For Evaluating Blasted Or Shot Peened Surfaces, Stefanie Stoeckel, Sophie Groeger

15th International Conference on Shot Peening

A review of the papers presented at the last three International Conferences on Shot Peening revealed that the most used parameters are Ra and Rz. There has been comparatively little exploration of other parameters, particularly the S-parameters. Furthermore, the ISO 4287 standard for profile parameters was replaced by the new ISO 21920-2 standard in 2021. This is accompanied by the introduction of new parameters as well as alterations to existing ones. This paper demonstrates the limitations of Ra and Rz, as well as Sa and Sz, and explores additional areal and profile parameters that are useful for the description of …

E-Strip® Peening Intensity Sensor - Linearity, Variability And Connectivity, Sylvain A. Forgues, Brigitte Labelle, Ramzi Ben Moussa, Sebastien Beaugrand, Raphael Sarraillon, Sergio Amaya

15th International Conference on Shot Peening

This paper presents the E-Strip®, a novel electronic sensor developed by Shockform to digitally measure shot peening intensity at the part level. Motivated by the limitations of traditional Almen strips—namely, manual handling, time consumption, and susceptibility to human error—the E-Strip® offers a faster, more reliable, and connected alternative. Extensive testing confirmed the E-Strip® output maintains excellent linearity with Almen intensity across a wide range of media and impact levels (R² > 0.997), and its adjustable sensitivity ensures compatibility from low to high intensities. Variability studies showed the E-Strip® provides similar or better consistency than Almen strips at low intensities, although higher …

Improving Fatigue Strength And Life Of Single Crystal Cmsx-4, Jochen Peter Fuhr, Lloyd Hackel, Nicolau I. Morar, Noah Holtham, Keivan Davami, Montu Sharma, Rajkumar Roy

15th International Conference on Shot Peening

The deep penetration of laser peening (LP) and retention of residual stress at high temperature by LP is significant in improving fatigue life and strength of superalloys exposed to high temperature and corrosion. Single crystal CMSX-4, was evaluated for stress relaxation and both fatigue life and fatigue strength of material that was LP-treated compared to non-LP and shot-peened (SP) specimens. LP was done with multiple layers using a 20 J/pulse laser where the laser high energy enabled using a 5 mm spot size on the metal surface. Stress measurements by the slitting technique showed the plastic penetration depth exceeded SP …

Application Of Burnishing Process Expected To Frictional Heat To Non-Oriented Electromagnetic Steel Sheet, Yuji Kobayashi, Masato Okada

15th International Conference on Shot Peening

Burnishing is a technology used to improve the surface roughness of metals. On the other hand, it is expected that the metal structure near the surface will change due to strong distortion.

The magnetic properties of electromagnetic steel sheets depend on large crystal grains and fine crystals near the surface[1]. In particular, thinner fine crystal grain layers on the surface are expected to reduce iron loss. In this study, the power generation characteristics of Burnished electromagnetic steel sheets were evaluated.

Electromotive force waveform was evaluated by rotating the laminated electromagnetic steel sheets and using a spindle motor. The electromotive force …

The Effects Of Shot Peening Highly Loaded Compression Springs, David J. Breuer

15th International Conference on Shot Peening

The compression spring in this test study is typical of one used in a demanding off-road vehicle suspension. The cyclic loads applied during fatigue tests were severe enough to cause failure in approximately 11,000 cycles without shot peening.

The objectives of this study were the following: (1) Design a compression spring similar to those used in the off-road recreational industry. (2) Design & manufacture a fatigue test stand that could withstand high loads for months of testing. (3) Generate a matrix of shot peening treatments to produce different amounts of residual compressive stress. (4) Measure the shot peening residual compressive …

Hands-On Stem In Ghana: Inspiration For Culturally Relevant Pedagogy Globally, Alhassan Issifu, Mawuena A. Hanson, Heather R. Beem

Journal of Pre-College Engineering Education Research (J-PEER)

Many educators are increasingly seeking culturally relevant pedagogies they can employ to effectively engage their students. In Ghana a substantive set of hands-on STEM content has been created, incorporating locally available materials and cultural approaches while maintaining alignment to the national curricula. Against a backdrop of almost no public primary or junior high schools in the country containing any lab equipment, this approach leverages and celebrates the abundance of what is available within the locality. This challenges narratives of what is considered “good” and recenters power back with those in the classroom. Three sample activities and three firsthand stories are …

Community Survey Report: The Rebuild Survey Conducted In Response To The January 2025 Palisades Fire And Eaton Fire In Los Angeles County, Andrew J. Whelton, Cristiane Ferrarezzi, Lauryn Spearing, Anna Hoover, Mónica Palomo, Caitlin Proctor, Jianxi Su, Joseph Toland

Resilience to Emergencies and Disasters

No abstract provided.

The Potential Benefits Of Co-Design In Dog-Assisted Treatment Programs For Veterans Seeking Mental Health Care, Parvin (Pary) Bahmanyari, Pauleen Bennett, Tiffani Howell

People and Animals: The International Journal of Research and Practice

Veterans are more likely than the general population to experience a range of mental health problems. While many veteran mental health support programs are available, veterans may struggle to access and engage with these services for various reasons (e.g., a stigmatized perception of mental health disorders, mistrust). Animal-assisted services have become more popular in civilian and military health care settings where traditional therapies (e.g., cognitive behavioral therapy) may not always be effective. Assistance dogs, for example, which live with veterans to provide disability support, have been successfully employed for veteran mental health. Unfortunately, a subgroup of veterans may miss out …

Novel Biomolecule-Infused Gelatin Injectable For Treatment Of Recurrent Laryngeal Nerve Injury, Ananya Tadikonda, Sunjay Anekal, Lena W. Chen, Gabriel Sobczak, Troy Wesson, Carmilya Jackson, Marisa A. Egan, Julie C. Liu, Patrick R. Finnegan, Stacey Halum

School of Chemical Engineering Faculty Publications

Objective

Unilateral vocal fold paralysis (UVFP) due to recurrent laryngeal nerve injury (RLN) is a major cause of voice disorders. We have recently identified three biomolecules (agrin, acetylcholine, and neuregulin) with the potential to promote reinnervation after RLN injury. This study aimed to determine if a gelatin injectable with the reinnervating biomolecules will induce site-specific amplification of neurotrophic factor release and reinnervation after RLN injury in unilateral vocal fold paralysis.

Methods

C57BL/6 mice underwent RLN transection with the following treatment allocations: saline control (N = 16), biomolecule cocktail only (N = 16), and biomolecule-infused gelatin (N = …

Robotic System With Tactile-Enabled Leaf Tracking For High-Resolution Hyperspectral Imaging Device For Autonomous Corn Leaf Phenotyping In Controlled Environments, Xuan Li, Ziling Chen, Raghava Uppuluri, Pokuang Zhou, Tianzhang Zhao, Darrell Zachary Good, Yu She, Jian Jin

School of Industrial Engineering Faculty Publications

Hyperspectral imaging of individual corn leaves provides valuable data for analyzing nutrient content and diagnosing diseases. However, existing leaf-level imaging techniques face challenges such as low spatial resolution and labor-intensive processes. To address these limitations, this study developed a robotic system integrated with a high-resolution line-scanning hyperspectral imaging device to autonomously scan a corn leaf. The hyperspectral imaging device used a vision-based tactile sensor for active leaf tracking throughout the scanning process, ensuring high image quality. Additionally, the device incorporated an in-hand leaf manipulation mechanism that ensured the leaf was properly positioned on the tactile sensing area at the start …

A Feasibility Study Into The Usability And Application Of An Unmanned Aerial Vehicle For Aircraft Inspection And Quality Assurance Inspections, Reece P. Bhave

Journal of Aviation Technology and Engineering

The global aviation industry is often characterized as one of the safest modes of transportation in the modern world. With an abundance of quality assurance inspections and checks to determine operations safety, modern-day commercial aircraft that are utilized for passenger and cargo flights are held to a higher safety standard defined by regulatory bodies, such as the Federal Aviation Administration in the United States of America and the European Union Aviation Safety Agency in the European Union. While these quality standards are maintained via a series of inspections, checks, and preventative maintenance procedures, they are limited to only visual or …

Activity Design Principles To Support Engineering Engagement For Families With Preschool-Age Children From Low-Income English-And Spanish-Speaking Communities, Scott A. Pattison, Smirla Ramos Montañez, Viviana López Burgos, Gina Svarovsky, María Quijano, Amy Corbett, Catherine Wagner, Diana Contreras

Journal of Pre-College Engineering Education Research (J-PEER)

Existing evidence highlights the significance of family STEM learning experiences during early childhood. However, there is a lack of research specific to early childhood family-based learning in the field of engineering, especially with preschool-age children (three to five years old). To address this gap and inform engineering education programs for young children, we conducted a design-based research study in collaboration with 15 Spanish-and English-speaking families with preschool-age children from low-income communities. Our study aimed to develop and test a series of family-based engineering design activities while also identifying underlying design principles. Guided by an asset-based family learning framework, which acknowledges …