December 03, 2013 Volume 09 Issue 45

Mechanical News & Products

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Cool! Internal threading in hard materials now possible

INSACO has a new capability where they can machine an internal thread in ceramic, sapphire, quartz, and other very hard materials. This advance pushes the boundaries of what's possible to support advanced applications that demand high precision and complexity. Ultra-hard materials are alternatives for when metal can't do the job. Ideal for aerospace, medical, and industrial applications.
Learn more. Video available on right side of page.


ClampDisk micro fastener is new alternative for automotive and consumer electronics

Designed as a unique alternative in assemblies for the automotive and consumer electronics markets, the ClampDisk Press-on Fastener is a newer offering from PennEngineering that delivers a fast, simple way to achieve sheet-to-sheet clamped fastening while replacing the use of standard screws, nuts, and adhesives. ClampDisk eliminates over-installation, cross-threading, stripped screw heads, broken screws, and damaged product. This fastener can be removed easily with a sharp-edged tool.
See how ClampDisk works.


Simplify appliance glass assembly

Henkel's Technomelt PUR 9015 BV/WV is a polyurethane hotmelt adhesive providing high initial strength and long-term durability for glass and large-panel appliance assembly. It enables immediate handling, excellent substrate adhesion, and high thermal resistance, while supporting automated, cost-efficient production. It offers a flexible solution for high-reliability manufacturing.
Learn more.


Made-to-order stamped components for insert molding

Traditionally, OEMs source metal inserts and insert molding services separately. Not anymore. Plastics manufacturers and injection molders are now taking on more of the sourcing responsibility for insert molded parts, and they are partnering with Boker's, who has a long-term proven record for delivering precision stampings with quick turnaround times and ensuring metal inserts are mold-ready upon delivery. Boker's has immediate access to over 2,000 commonly specified and hard-to-find materials.
Learn more.


SDP/SI Shaftloc Fastening System

Shaftloc is a unique, reusable locking device for securely mounting mechanical components like gears and sprockets onto shafts without the need for keyways, set screws, or adhesives. Its simple, two-piece design offers a cost-effective alternative to traditional fasteners, providing high clamping force and vibration resistance. Installed with standard tools, Shaftloc is perfect for designers seeking flexible, hubless mounting solutions. Available in four styles.
Learn more from SDP/SI.


Epoxy engineered for heat-sink bonding

Master Bond EP54TC is a two-component epoxy engineered for heat-sink bonding and thermal management applications. Featuring the highest thermal conductivity in the Master Bond electrically insulating portfolio, it delivers exceptional heat dissipation while remaining electrically non-conductive and compliant with ASTM E595 NASA low outgassing requirements. It supports thin bond lines and efficient void filling to maximize thermal performance.
Learn more.


Metal 3D printing: Right at your desktop

From prototyping to tooling or batch production of end-use parts, the Studio System 2 from Desktop Metal brings metal 3D printing to any office, studio, or lab setting. This powder- and laser-free system consists of an easy-to-adopt two-step process: print using pre-bound metal rod feedstock and then sinter. It requires minimal training and operator intervention. Combined with next-gen Separable Supports and a software-controlled workflow, the Studio System makes metal 3D printing simpler than ever. This platform offers more materials than any other metal extrusion 3D-printing system on the market, including Inconel 625, titanium (Ti64), copper, tool steels, and stainless steels.
View the video and learn more.


Metal 3D printing: EOS adds four new materials

Industrial 3D-printing supplier EOS has added four new metal additive manufacturing materials to its portfolio: an iron-nickel alloy that boasts stability under fluctuating temps, a nickel alloy with high strength and extreme corrosion resistance, a low-alloyed steel prized for its high toughness and strength, and an industrial-grade stainless steel. Each has been optimized for EOS Laser Powder Bed Fusion systems.
Get all the details.


Application Note: Disc springs in mechanical braking system

Braking systems for off-highway equipment are commonly designed to be hydraulically actuated, but without an additional fail-safe system, this design alone has limited reliability. If a hydraulic seal is compromised, or the hydraulic cylinder loses pressure for any reason, the brakes fail. One solid mechanical back-up design uses SPIROL disc springs.
Read the full article.


Configurable welding platform for flexible manufacturing

Emerson's new Branson Polaris Ultrasonic Welding Platform offers a highly configurable, smart solution for advanced manufacturing. It features secure connectivity and real-time control to join diverse materials, from medical devices to food packaging. With adaptable power supplies and actuators, the system scales from benchtop lab trials to fully automated production lines, optimizing footprint and data storage to meet complex application needs.
Learn more.


SPIROL receives 2025 Supplier Excellence Recognition Award from Caterpillar

Kudos to SPIROL! The engineered fasteners manufacturer has received the 2025 Supplier Excellence Recognition Award from Caterpillar Inc. This prestigious award recognizes suppliers who demonstrate world-class performance and a sustained commitment to quality, delivery, and operational excellence.
Read the full article.


Eliminate cotters, bolts, nuts with SLIC Pin®

The SLIC Pin (Self-Locking Implanted Cotter Pin) from Pivot Point is a pin and cotter all in one. This one-piece locking clevis pin is cost saving, fast, and secure. It functions as a quick locking pin wherever you need a fast-lock function. It features a spring-loaded plunger that functions as an easy insertion ramp. This revolutionary fastening pin is very popular and used successfully in a wide range of applications.
Learn more.


Tech Tip: How to install sleeve bearings

According to the engineering experts over at PBC Linear, "Installing Simplicity Sleeve Bearings can be tricky due to the thin aluminum outer shell." Learn the basic procedures that can be followed to install the aluminum-backed Simplicity Sleeve and Flange Bearings -- each comes with its own unique challenges.
Read the PBC Linear blog.


Hold any shape with ID and OD Form Holding Clamps

These simple OD and ID clamping solutions from Fixtureworks clamp onto your part in one easy operation, eliminating the need for custom fixtures. They allow users to clamp onto the inner or outer diameter of small-size, irregularly shaped work parts fast. Lots of options.
Learn more.


Engineer's Toolbox: The basics of pressure regulators

Pressure regulators are found in many common home and industrial applications. Learn all about their functions, selection criteria, installation, and more in this in-depth article from Beswick Engineering.
Read the full article.


Cracked metal heals itself to the astonishment of MIT scientists

Unexpected result shows that in some cases, pulling apart makes cracks in metal fuse together.

By David L. Chandler, MIT

It was a result so unexpected that MIT researchers initially thought it must be a mistake: Under certain conditions, putting a cracked piece of metal under tension -- that is, exerting a force that would be expected to pull it apart -- has the reverse effect, causing the crack to close and its edges to fuse together.

The surprising finding could lead to self-healing materials that repair incipient damage before it has a chance to spread. The results were published in the journal Physical Review Letters in a paper by graduate student Guoqiang Xu and professor of materials science and engineering Michael Demkowicz.

"We had to go back and check," Demkowicz says, when "instead of extending, [the crack] was closing up. First, we figured out that, indeed, nothing was wrong. The next question was, 'Why is this happening?'"

The answer turned out to lie in how grain boundaries interact with cracks in the crystalline microstructure of a metal -- in this case nickel, which is the basis for "superalloys" used in extreme environments, such as in deep-sea oil wells.

By creating a computer model of that microstructure and studying its response to various conditions, "We found that there is a mechanism that can, in principle, close cracks under any applied stress," Demkowicz says.

Video: A computer simulation of the molecular stucture of a metal alloy, showing the boundaries between microcystalline grains (white lines forming hexagons), shows a small crack (dark horizontal bar just right of bottom center) that mends itself as the metal is put under stress. This simulation was one of several the MIT researchers used to uncover this new self-healing phenomenon. Simulation courtesy of Guoqiang Xu and Michael Demkowicz.

Most metals are made of tiny crystalline grains whose sizes and orientations can affect strength and other characteristics. But under certain conditions, Demkowicz and Xu found, stress "causes the microstructure to change: It can make grain boundaries migrate. This grain boundary migration is the key to healing the crack," Demkowicz says.

The very idea that crystal grain boundaries could migrate within a solid metal has been extensively studied within the last decade, Demkowicz says. Self-healing, however, occurs only across a certain kind of boundary, he explains -- one that extends partway into a grain, but not all the way through it. This creates a type of defect is known as a "disclination."

Disclinations were first noticed a century ago, but had been considered "just a curiosity," Demkowicz says. When he and Xu found the crack-healing behavior, he says, "it took us a while to convince ourselves that what we're seeing are actually disclinations."

These defects have intense stress fields, which "can be so strong, they actually reverse what an applied load would do," Demkowicz says: In other words, when the two sides of a cracked material are pulled apart, instead of cracking further, it can heal. "The stress from the disclinations is leading to this unexpected behavior," he says.

Having discovered this mechanism, the researchers plan to study how to design metal alloys so cracks would close and heal under loads typical of particular applications. Techniques for controlling the microstructure of alloys already exist, Demkowicz says, so it's just a matter of figuring out how to achieve a desired result.

"That's a field we're just opening up," he says. "How do you design a microstructure to self-heal? This is very new."

The technique might also apply to other kinds of failure mechanisms that affect metals, such as plastic flow instability -- akin to stretching a piece of taffy until it breaks. Engineering metals' microstructure to generate disclinations could slow the progression of this type of failure, Demkowicz says.

Such failures can be "life-limiting situations for a lot of materials," Demkowicz says, including materials used in aircraft, oil wells, and other critical industrial applications. Metal fatigue, for example -- which can result from an accumulation of nanoscale cracks over time -- "is probably the most common failure mode" for structural metals in general, he says.

"If you can figure out how to prevent those nanocracks, or heal them once they form, or prevent them from propagating," Demkowicz says, "this would be the kind of thing you would use to improve the lifetime or safety of a component."

The work was funded by the BP-MIT Materials and Corrosion Center.

Published December 2013

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