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December 2018

Piselli Enterprises

Piselli Enterprises provides its customers with the best solutions to fit their manufacturing needs, whether it’s parts, machines, or consultation services that can help take a customer to the next successful level.

When it comes to the gear industry, Rich Piselli just couldn’t stay away. Piselli is president and founder of Piselli Enterprises, a venture he started in 2016. But Piselli’s expertise with the gear market reaches back decades, and it is that extensive knowledge that is a major crux of his most recent foray into the […]
Kenneth Carter

The Root Cause for Gear Noise Excitation

Though focused primarily on parallel-axes gearings, the following methods are also valid for gear pairs with intersected axes of rotation, as well as crossed-axes
of rotation of the gears.

This article is about noise excitation and vibration generation in gear drives when the gear drives operate. It is shown that transmission error is not the root cause for the noise excitation as it is commonly meant. Instead, transmission error is a consequence of deviation of base pitches of a gear and a mating pinion […]
Dr. Stephen P. Radzevich Ph.D., Dr. (Eng) Sci.

How Polyketone Polymers Improve Gear Performance

Superior wear properties, better dimensional control/stability, superior creep rupture performance, and quieter operation are a few of the benefits these polymers provide.

Engineers have been using thermoplastic resins to produce gears used in assemblies for the automotive, appliance, business equipment, and other market segments for many years. Thermoplastics offer several improvements over metals, including lower cost, less noise, and lighter weight, along with less energy loss due to frictional heat generation in non-lubricated gear sets. Historically, the […]
Tim Morefield

Psychoacoustic Methodology for the Noise Reduction of Bevel Gears

How Fast Fourier Transformations of single flank errors can be used during the development of a gearset to establish harmonic levels and side bands of quiet rolling gearsets.

The relationship between FFTs and gear quality as well as gear noise is investigated with some surprising conclusions, which leads to the discovery of a new interpretation of higher harmonics and the unknown influence of the residual error. An excursion into the psychoacoustic science in this phase of the research delivered many useful answers. Finally, […]
Dr. Hermann J. Stadtfeld

November 2018

Tooling Profile: Euro-Tech Corporation

Euro-Tech Corporation has been offering quality spline gaging, hydraulic expansion arbors and chucks, as well as custom engineered solutions for a quarter of a century.

Euro-Tech Corporation prides itself as having a limited number of highly–engineered solutions in the fields of profile gaging and workholding. Those high-end solutions often translate into working with its customers from the beginning of a challenge, essentially starting from scratch more often than not. “Our philosophy is not to have a book or catalog of […]
Kenneth Carter

Services Profile: Excel Gear Inc.

Excel Gear Inc. has been involved in machine tool design, gearbox design and manufacturing, wind-turbine gearboxes, gear manufacturing, and more almost three decades.

The gear industry has been slowly changing over the last 10 years, and Excel Gear has worked hard to change with it, offering ground tooth gearing as well as working with complex military projects. “We hob gears up to two meters in diameter, and we tooth grind to a meter and half,” said Dan Herr, […]
Kenneth Carter

Machines Profile: Reishauer

Worldwide, Reishauer gear grinding machines play a major role in the manufacturing process of grinding gears used in automobiles, aircraft, and construction/agricultural machinery.

Since its founding in 1788, Reishauer has moved from manufacturing precision thread cutting tools to being a market leader in precision gear grinding machines. “Automobiles, aircraft, and construction/agricultural machinery all require high-accuracy gears for their transmissions,” said Walter Graf, marketing manager with Reishauer. “Worldwide, Reishauer gear grinding machines play a major role in the manufacturing […]
Kenneth Carter

October 2018

Ganesh Industries

Ganesh Industries provides its customers with complete satisfaction by providing high-quality, well-engineered machines, and outstanding after-sale service.

Humble beginnings as a small family business are still the driving force behind Ganesh Industries, even though the company has grown exponentially since it opened its doors in 1985. And that means that — as well as offering quality machines — Ganesh offers quality customer satisfaction, according to Kamal Grewal, marketing/sales director for Ganesh Industries. […]
Kenneth Carter

The critical role of deburring

The CI machine from EMAG ECM provides a highly effective solution for deburring complex components.

Autonomous steering and brake systems, hydro-pneumatic chassis, or radically improved gas mileage — these buzzwords represent a technological change that is triggering a domino effect in the automotive and other industries. An increasing number of components have to satisfy extremely demanding quality requirements. They need to leave the production process in perfect condition and without […]

Heat treating low alloy PM steels

Examining the influence of tempering parameters on the microstructure and mechanical properties of heat-treated, low-alloy PM steels.

Tempering is a heat-treatment technique used to improve the strength, ductility and toughness of hardened carbon steels. Tempering occurs by heating the steel to below its critical temperature in order to transform the metastable body-centered tetragonal martensite structure that is formed during quenching into a more stable structure of fine carbide particles. Choosing the correct […]
Amber Neilan, Roland Warzel III, Bo Hu, Bob Aleksivich

September 2018

Norton | Saint-Gobain

With a rich history of innovative technology and excellent customer service, Norton | Saint-Gobain has consistently delivered quality gear-grinding products for more than a century.

Over the last 30 years, the gear industry has changed by leaps and bounds. And as it has changed, Norton | Saint-Gobain, one of the world’s largest abrasives manufacturers, has kept pace with its state-of-the-art grinding products. Gear grinding for generating the profile of gear teeth has become an important aspect of the industry. “In […]
Kenneth Carter

Calculation of Tooth Flank Fracture Load Capacity

Sophisticated methods for assessing the risk of tooth flank fracture have been available for a long time, but industry now demands simplified and standardized calculation methods.

1: Introduction Due to improved material qualities, new surface finishing methods and increased heat-treatment process reliability, flank surface damages, such as pitting or micropitting, can be prevented more and more in a reliable manner. This results in an increase of unexpected flank damages with crack initiation below the surface of the loaded gear flank(s), for […]
Prof. Dr.-Ing. Karsten Stahl, Michael Hein, Thomas Tobie

Advances in the Production of Double Helical Gears

Increasing demand for double helical gears in planetary reduction gear boxes for engines in civil aviation has necessitated a number of new capabilities and technologies.

Double helical gears (herringbone gears) are characterized by a symmetric arrangement of two identical gear teeth with exactly opposite helix angles. As a result of this symmetry, the axial forces in the gearbox negate each another. For many years, such double helical gears, as an example for components with geometrical interference, have been a special […]
Holger Staub

Flexibility is Key to Aftermarket Success

An aftermarket business unit should look for solutions that marry technology with fresh green talent and bulletproof procedures as a model for achieving success.

Staying lean and profitable has always been a challenge for aftermarket gear manufacturing. Expedited delivery demands, legacy product support, unpredictable product volumes, limited warehouse space, and the expenses associated with keeping stored parts in sellable condition can make or break an aftermarket business plan. Supply chains and scheduling are chaotic at best, machine efficiency is […]
Will Terry

August 2018

Wenzel America

Wenzel America is an innovative provider of customized metrology solutions, built on a solid foundation of German precision engineering and strong partnerships as a family-owned company.

With thousands of customers around the world using Wenzel machines, the company is considered a leader in the metrology industry. Its focus is on solving the toughest measuring requirements for its customers, wielding its longtime expertise in German engineering, which dates back to 1968. Parent company Wenzel Präzision GmbH was founded by Werner Wenzel in […]
Gear Solutions staff

Modular Sealing Solution Ideal for Automation

An innovative sealing system has been developed especially for industrial applications where robustness and long lifespans of gears are in demand, including robots and automation.

Across every industry, today’s state-of-the-art manufacturing environment emphasizes variable batch sizes, flexible processes, and high availability. These factors are placing higher demands on individual components, including gear motors, in the manufacturing process. Used to drive conveyor belts and assembly lines, the longevity and strength of gear motors are critical factors in increasing productivity and improving […]
Marcel Santos, Benjamin Kohl

Areal Evaluation of Involute Gear Flanks with 3D Surface Data

How examinations of involute gear flanks using areal, three-dimensional surface data provide in-depth, holistic information about the gears.

With the evolution of size, weight, surface structure, and tolerance requirements in gear production and application, gear metrology is challenged at the same time to fulfill the cycle time requirements and to support the varieties in gear dimensions and geometry. The standard gear flank inspection is based on measuring two-dimensional line features (classically one profile […]
Yue Peng, Kang Ni, Gert Goch

The Effects of Shrouding on reducing Meshed Spur Gear Power Loss

Insights from NASA aeronautics rotorcraft research aimed at propulsion technologies that improve efficiency while minimizing vehicle weight.

Gearbox efficiency is reduced at high rotational speeds due to windage drag and viscous effects on rotating, meshed gear components. A goal of NASA aeronautics rotorcraft research is aimed at propulsion technologies that improve efficiency while minimizing vehicle weight. Specifically, reducing power losses to rotorcraft gearboxes would allow gains in areas such as vehicle payload, […]
I.R. Delgado, M.J. Hurrell

July 2018


ZOLLER Inc. combines hardware, software, and services to create optimal system
solutions for presetting, measuring, inspection, and management of tools.

With a focus on cutting tools and the solutions around them, ZOLLER Inc.’s place in the machine tool universe holds a special philosophy. ZOLLER prides itself in being not just a supplier, but a strategic partner in the industry, according to Rita Conroy-Martin, director of marketing for ZOLLER Inc. “I think that’s a unique advantage […]
Kenneth Carter

 A driving force in workholding

Once thought to be primarily for long and straight cylindrical shafts requiring turning between centers, savvy operators now know anything that can be placed and turned between centers can be done with a face driver.

Over the years, companies performing turning operations have come to realize the versatility of using face drivers as a complete workholding solution. Along the way, they have continued to gain greater acceptance for a multitude of turning applications. The major benefit of a face driver is found in its ability to allow the part to […]
Jay Duerr

Precision measuring  with hand tools

In order to achieve reliable measurements from precision hand tools,
a common-sense approach on basic usage produces the best results.

Developments in precision measuring have made modern hand tools more accurate and easier to read. Reviewing basic tips for “how to” use precision instruments can help operators use the tools to their full potential and ultimately save time, reduce errors, and increase productivity.  This article covers tips of the trade for measuring with three popular […]
Scott Robinson

Why customized workholding?

Selecting the best workholding system for your specific needs will ultimately lead to a better end product. Close communication with your vendor results in the best tailored system.

With manufacturing operations using higher cutting speeds that place greater force on workholding equipment, choosing the correct system to hold your work is trickier than ever. Careful examination of your clamping application may lead you to either a ready-made solution or a customized workholding answer. To provide these answers, Emuge Corp. has a workholding division […]
David Jones

Heat Treatment of Steel Gears

The important heat-treating processes during gear manufacturing include preparation treatments before machining or hardening, and hardening treatments.

Gears enable motion through power transfer in key sectors, including automotive, aerospace, marine, off-highway, and industrial applications. The gear manufacturing industry is estimated to be worth more than $45 billion, 75 percent of which is accounted for by the automotive sector alone [1]. A typical steel gear manufacturing process (Figure 1) starts with a forging, […]
Satyam Sahay

You Say You Want a Lubrication Revolution?

With many possible benefits and applications, the potential of hydro lubricants is only beginning to be harnessed.

By using water as a functional component in specialty lubricants, there is a whole new range of opportunities that can employ the revolutionary properties of hydro lubricants to realize advantages that include: Enhancing operational excellence by reducing friction by a factor of 10 and significantly extending component service life. Improving plant hygiene and occupational health […]
Kluber Lubrication NA LP

Forward thinking about reverse engineering

A basic guide to determining a gear’s original form requires taking many factors into consideration, including geometry, manufacturing method, and application.

When approaching a project requiring reverse engineering, questions must be asked that may seem simplistic, but will determine the failure or success of your efforts. The first questions to pose include: How will this image be used? Do I anticipate any changes? What are your tolerance requirements? All these questions are paramount in determining the […]
Greg Groth

New  technologies pay major dividends

Machine designs focusing on mass production, batch and small-lot processing, as well as providing ‘Closed Loop’ feedback increase throughput and improve the quality of the finished part.

In order that productivity can be realized, gear producers need systems designed for simplifying and automating common tasks so that less experienced workers can perform reliably. This article outlines the strides made in simplifying and automating tasks for generating grinding. This includes: Exchange of tooling such as abrasive, dresser and clamping arbor. Quality maintenance. First […]
Bill Miller

 Addressing internal integrity

As the gear industry changes, it’s important that inspection methods adapt to address the challenges that come with it.

Gear inspection is a critical aspect for producing a quality product. Jesse Garant of Jesse Garant Metrology Center recently sat down with Gear Solutions to discuss the importance of inspection and how it has grown to service the changing gear manufacturing industry. Why is gear inspection important? Gear inspection is important to validate not only […]
Kenneth Carter

June 2018

Wolverine Broach Co. Inc.

Wolverine Broach Co. Inc. has developed a reputation for craftsmanship, design, engineering, and support services.

Broaching can be quite the competitive arena in the manufacturing world, so it’s imperative for a company to take those extra steps to bring customers to its door. At Wolverine Broach Co. Inc., company President Bernard J. Aude Jr. prides himself in that ability. “We’re considered a small organization, which allows us to fly under […]
Kenneth Carter

Evaluating the Unknown Geometry of High Accuracy Gearing

Finding the addendum modification coefficient using the base tangent length (BTL) method is found to be useful for gear parameter evaluation of an unknown gear.

By Prasmit Kumar Nayak, A. Velayudham and C. Chandrasekaran Evaluation of geometry of used and broken gear is a seldom practice followed in the fields such as maintenance repair and recycling. Although gear calculations and main parameters are standardized, this task can be complicated, especially when there is no information about mating gear and gearbox assembly, […]
Prasmit Kumar Nayak

Driving Gear Development

Gleason technologies help SEW Eurodrive meet global demand for compact, quiet, and very high-efficiency spiral bevel gear units.

Ask Chuck Chandler, plant manager at SEW Eurodrive USA in Lyman, South Carolina, about the range of applications for the spiral bevel gear units produced there, and his response is simple: the world. The ultra-modern 385,000-square-foot facility, winner of Plant Engineering Magazine’s Top Plant Award in 2007, is running three shifts a day, six days […]
Uwe Gaiser

Gear Tooth Strength Analysis of High Pressure Angle Cylindrical Gears

High pressure angle gears are not expected to show better mechanical behavior in high power transmissions than gears with conventional designs.

The gear tooth strength of high pressure angle gears is studied and compared with that of conventional pressure angle gears. The comparison is carried out regarding contact pressure, contact and bending stresses, and the loaded function of transmission errors. The gear geometric models are generated by the computerized simulation of the manufacturing process, and the […]
Alfonso Fuentes-Aznar, Ignacio Gonzalez-Perez

May 2018

Lawler Gear Corp.

On the cutting edge: Lawler Gear is about to celebrate 40 years of supplying its customers with a variety of gears, CNC gear hobbing, gearbox rebuilding, and many other services.

Lawler Gear Corp. has seen a lot of changes in the gear manufacturing industry since it opened its doors 40 years ago. Ironically, the gear company has not seen a lot of changes in its staff. “One of the unique things about us is our crew,” said Ray Lawler, president of Lawler Gear Corp. “Our […]
Kenneth Carter

Meeting Manufacturing Tolerances with FE-Based Design

This article discusses an FE-based method for the design of robust tooth flank modifications for cylindrical and planetary gear stages.

By Prof. Dr.-Ing. C. Brecher, Dr.-Ing. C. Löpenhaus, Julian Theling, Marius Schroers, and Dipl.-Ing. Daniel Piel Tooth flank modifications are used to optimize the excitation behavior and durability of gears. In the first step, design is often done via guidelines, and afterwards, a variety of tooth flank modifications is checked via local calculation approaches to […]
Prof. Dr.-Ing. C. Brecher

Continuous improvement in generating gear grinding

Seeking an overview of a process so critical to the gear manufacturing industry, Gear Solutions reached out to a longtime expert on gear grinding technology.

With many years of development, generating gear grinding is at a highly evolved point. It is no longer a question of any mainline gear grinder being able to produce a high-quality gear. Grinding times from various manufacturers are all within a tight range. In this race, all the top competitors are neck-and-neck. Has stasis been […]
Dwight Smith

Lubrication and wear in forging

Although lubricant is continuously exposed to changing pressures and velocities and differing degrees of wear, a dynamic equilibrium – and, therefore, realistic data – may be attained through careful control.

Both hot and cold forging are batch-type processes in which steady-state conditions are never fully achieved and the initial lubricant supply must perform adequately for the duration of the operation. The lubricant is continuously exposed to changing pressures and velocities, and wear or pickup products in the lubricant also continuously vary, although a dynamic equilibrium […]
K.D. Clarke, C.J. Van Tyne

April 2018

A Competitive Edge Starts at the Spindle

These high torque retention knobs were specially designed to help machining centers achieve optimized toolholder productivity.

Despite some 750,000 CNC mills put into service in the United States over the past 15 years, CNC machining job shops often hover at the bottom of the totem pole where there’s little room for error, as most bids are won by a 1-2 percent price variance. Representing the backbone of the U.S. machinery resurrection, […]
John Stoneback

Choosing a Resharpening Resource

Cutting tool management is a critical aspect of gear manufacturing operations, and expert resharpening services are worth their weight in accumulated chips.

On a per-unit basis, the overall cost of cutting tools in a gear cutting process boils down to only a few percentage points. As a result, this overshadows the cutting tool’s obvious direct impact on the cutting process and cut gear. Consequently, some gear manufacturing operations focus elsewhere to find productivity gains, better quality, or […]
Adam Gimpert

Effects of Asymmetric Cutter Tip Radii on Gear Tooth Root Bending Stress

When fillet geometry is modified and controlled for decreasing bending stress, improved gear service life is the primary result.

By Dr. Abdullah Akpolat, Dr. Nihat Yildirim, Burak Sahin, Omer Yildirim, Bulent Karatas, and Fatih Erdogan Tooth root fillet is the maximum bending stress concentration region during a torque transmission via gear pairs. Increase in gear root fillet radius due to a larger cutter tip radius provides a smoother transition from involute to root via a […]
Abdullah Akpolat

Introducing the New Blue

New segmented collet design meets the industry’s need for reliable, accurate, and universal bore clamping for a wide range of cylindrical gear production applications.

Gear manufacturers today must turn on a dime to meet fast-changing customer demand and marketplace conditions with faster production of smaller lot sizes. More frequent part changeover has fostered the development of workholding systems with quick-change, often tool-less designs to take increasingly valuable non-productive time out of the process. This new gear production paradigm has […]
Timothy Zenoski

March 2018

JM Performance Products

JM Performance Products has established itself as a model shop leader for manufacturing development and quality control of precision-turned parts.

JM Performance Products may be a small company, but the products and services it offers are anything but. “We are a small company that manufactures with the traceability and quality standards gained from years working from a defense manufacturer’s standpoint,” said Plant Manager Craig Fischer. “We buy all U.S. steel. Our products are guaranteed not […]
Kenneth Carter

Induction Gear Hardening: Part 2

The second in a two-part series, this installment addresses induction gear hardening by encircling the whole gear or sprocket with an induction coil,
also known as ‘spin hardening.’

This is the second installment of a two-part article on induction hardening of gears and gear-like components. Part 1 was published in the February 2018 issue of Gear Solutions magazine, covering the following subjects: Materials selection for induction gear hardening, including specifics of electromagnetic induction vs. thermo-chemical diffusion processes (e.g., carburizing). Impact of friendly vs. […]
Valery Rudnev

Root Fillet Optimization of Gears with Asymmetric Teeth

This paper provides an analysis of the benefits of optimizing the tooth root fillet of thin rim planet gears with asymmetric teeth.

By Dr. A.L. Kapelevich and Dr. Y.V. Shekhtman The Direct Gear Design method optimizes various parameters and elements of gear tooth geometry to achieve the required gear drive performance. One such critical element of the tooth profile is the root fillet. Its optimization by means of Direct Gear Design provides the ultimate bending stress minimization. […]
Dr. Alexander Kapelevich, Dr. Yuriy Shekhtman

Improving the Friction Power of Gears and Bearings

Proper lubrication can extend the overall fatigue life of gears by a factor of 2.6.

A machine that runs endlessly without any wear and frictional losses — who wouldn’t dream of that? Unfortunately, such a machine does not exist yet. However classic car fans know that through solid technology and ongoing service, cars can even outlast their owners. However, this does not happen with machinery of all industries. In the […]
Stefan Bill

CFD Simulation of Power Losses and Lubricant Flows in Gearboxes

Growing interest in the energy efficiency of gearboxes has led to the use of Computational Fluid Dynamics (CFD) to calculate load-independent power losses as well as lubricant flows.

Printed with permission of the copyright holder, the American Gear Manufacturers Association, 1001 N. Fairfax Street, Suite 500, Alexandria, Virginia 22314. Statements presented in this paper are those of the authors and may not represent the position or opinion of the American Gear Manufacturers Association. (AGMA) This paper was presented October 2017 at the AGMA […]
Franco Concli, Carlo Gorla

February 2018


TRUMPF may have started as a machine tool company, 
but laser manufacturing has made it a shining industrial star.

TRUMPF has been manufacturing for nearly a century but lasers energized the company’s mission, changing it forever. “In the late ’70s, we made one of the most important decisions in our company’s history, which was to develop laser technology,” said Ralf Kimmel, general manager and head of the Laser Technology division at TRUMPF Inc. “Cutting […]
Kenneth Carter

Induction Gear Hardening

Part 1: The practice and science of modern induction heat-treating has 
advanced in many areas over the last decade, including computer modeling, power supplies, failure analysis, quality assurance, and more.

Over the years, gear manufacturers have increased their knowledge of the production of quality gears and gear-like components. This knowledge has led to many improvements including lower noise, lighter weight, and lower cost as well as increased load-carrying capacity to handle higher speeds and torque with a minimum amount of generated heat. Improvement in wear […]
Valery Rudnev

Choosing a Planetary Gearhead

Motion projects featuring planetary gearheads excel in the areas 
of system response, inertia matching, speed matching, system stiffness, 
and system resolution.

From CGI Inc. staff When a motor is being designed into a motion control system, all too often the benefits of a gearhead are realized much too late. Designing in a gearhead at the end of the project will many times cause delay and additional cost, which could have been prevented if it had been […]
Rick Frennea

January 2018

Bevel Gears (India) Pvt. Ltd.

Bevel Gears (India) Pvt. Ltd. has designed and manufactured bevel gears and bevel gearboxes for more than 40 years.

Bevel Gears (India) Pvt. Ltd. considers itself a “niche within a niche” when it comes to making and supplying bevel gears. “Our niche is bevel gears,” said Mushtaq Jamal, vice president of engineering and business development with Bevel Gears (India). “We manufacture straight, spiral, hypoids, and high ratio hypoids.” That niche within a niche comes […]
Kenneth Carter

Closed Loop Machining of Cylindrical Gears

Looking to raise the quality and accuracy of your gearing? Consider Closed Loop design and manufacturing, which has done away with the error-prone data transfer from the measuring sheet.

Leonhard Euler’s 1760 invention of making cylindrical gears with an involute profile was the beginning of a success story. As a tooth profile, the involute has many advantages that are still being used by engineers to design high-performance transmissions that even function under high loads and the consequential deformation of the shaft bearing system. However, […]
Dr. Markus Brumm

Fatigue Performance and Cleanliness of Carburizing Steels for Gears

This investigation shows that steels with a higher cleanliness level reach a higher performance level as well, both in terms of increased loads and longer service life.

The cleanliness of steels used for gears is of great importance when looking to improve their life or increase loads. In this paper, carburizing steels with the same basic chemical composition, but with a varying cleanliness level, are compared in regards to cleanliness and performance. Steel cleanliness can be described as size and frequency of […]
Joakim Fagerlund, MSc, Lily Kamjou, MSc

Extending gear life in demanding applications

Specialized PVD coatings increase the surface hardness and durability of gears, thereby increasing their lifespan under high-load conditions.

Although gears and other precision components are generally made of hardened steel or metal alloys, those used in high load applications still can fail due to excessive wear, surface fatigue, pitting, galling, and corrosion. This is exacerbated in applications with metal-to-metal interaction, repetitive friction at high speeds or where little to no lubrication is present. […]
Jeff Elliot

Advanced Thermal Processing for Enhanced Gear Tribology

TriboNite technology can help improve gear performance by combining the well-known advantages of nitriding with the superior tribological performance profile of solid lubricant coatings.

By Boris Zhmud, Johan Blomkvist, and Mikael Fallström

Abstract Vast empirical knowledge accumulated over centuries, in conjunction with recent advances in the areas of material science, tribology, and big data analysis, have allowed significant progress in gear design. Still, gears sometimes fail. Gear tooth flanks are most vulnerable to damage under tribological stress. Gear material, machining, and finishing methods, lubricant, and end use […]
Boris Zhmud, Ph.D., FRSC, Mikael Fallström, M.Sc.