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hyperMILL 2024 CAD/CAM software suite

OPEN MIND Technologies has introduced its latest hyperMILL 2024 CAD/CAM software suite, which includes a range of powerful enhancements to its core toolpath capabilities, as well as new functionality for increased NC programming efficiency in applications ranging from 2.5D machining to 5-axis milling. New and enhanced capabilities include: Optimized Deep Hole Drilling, a new algorithm for 3- and 5-axis Rest Machining, an enhanced path layout for the 3D Plane Machining cycle, better error detection, and much more.
Learn more.

One-part epoxy changes from red to clear under UV

Master Bond UV15RCL is a low-viscosity, cationic-type UV-curing system with a special color-changing feature. The red material changes to clear once exposed to UV light, indicating that there is UV light access across the adhesive material. Although this change in color from red to clear does not indicate a full cure, it does confirm that the UV light has reached the polymer. This epoxy is an excellent electrical insulator. UV15RCL adheres well to metals, glass, ceramics, and many plastics, including acrylics and polycarbonates.
Learn more.

SPIROL Press-N-Lok™ Pin for plastic housings

The Press-N-Lok™ Pin was designed to permanently retain two plastic components to each other. As the pin is inserted, the plastic backfills into the area around the two opposing barbs, resulting in maximum retention. Assembly time is quicker, and it requires lower assembly equipment costs compared to screws and adhesives -- just Press-N-Lok™!
Learn more about the new Press-N-Lok™ Pin.

Why hybrid bearings are becoming the new industry standard

A combination of steel outer and inner rings with ceramic balls or rollers is giving hybrid bearings unique properties, making them suitable for use in a wide range of modern applications. SKF hybrid bearings make use of silicon nitride (twice as hard as bearing steel) rolling elements and are available as ball bearings, cylindrical roller bearings, and in custom designs. From electric erosion prevention to friction reduction and extended maintenance intervals, learn all about next-gen hybrid bearings.
Read the SKF technical article.

3M and Ansys train engineers on simulating adhesives

Ansys and 3M have created an advanced simulation training program enabling engineers to enhance the design and sustainability of their products when using tapes and adhesives as part of the design. Simulation enables engineers to validate engineering decisions when analyzing advanced polymeric materials -- especially when bonding components made of different materials. Understand the behavior of adhesives under real-world conditions for accurate modeling and design.
Read this informative Ansys blog.

New FATH T-slotted rail components in black from AutomationDirect

Automation-Direct has added a wide assortment of black-colored FATH T-slotted hardware components to match their SureFrame black anodized T-slotted rails, including: cube connectors (2D and 3D) and angle connectors, joining plates of many types, brackets, and pivot joints. Also included are foot consoles, linear bearings in silver and black, cam lever brakes, and L-handle brakes. FATH T-slotted hardware components are easy to install, allow for numerous T-slotted structure configurations, and have a 1-year warranty against defects.
Learn more.

Weird stuff: Moon dust simulant for 3D printing

Crafted from a lunar regolith simulant, Basalt Moon Dust Filamet™ (not a typo) available from The Virtual Foundry closely mirrors the makeup of lunar regolith found in mare regions of the Moon. It enables users with standard fused filament fabrication (FFF) 3D printers to print with unparalleled realism. Try out your ideas before you go for that big space contract, or help your kid get an A on that special science project.
Learn more.

Break the mold with custom injection molding by Rogan

With 90 years of industry experience, Rogan Corporation possesses the expertise to deliver custom injection molding solutions that set businesses apart. As a low-cost, high-volume solution, injection molding is the most widely used plastics manufacturing process. Rogan processes include single-shot, two-shot, overmolding, and assembly. Elevate your parts with secondary operations: drilling and tapping, hot stamping, special finishes, punch press, gluing, painting, and more.
Learn more.

World's first current-carrying fastening technology

PEM^® eConnect™ current-carrying pins from Penn-Engineering provide superior electrical connections in applications that demand high performance from internal components, such as automotive electronics. This first-to-market tech provides repeatable, consistent electrical joints and superior installation unmatched by traditional fastening methods. Features include quick and secure automated installation, no hot spots or poor conductivity, and captivation options that include self-clinching and broaching styles.
Learn more about eConnect pins.

New interactive digital catalog from EXAIR

EXAIR's latest catalog offers readers an incredible source of innovative solutions for common industrial problems like conveying, cooling, cleaning, blowoff, drying, coating, and static buildup. This fully digital and interactive version of Catalog 35 is designed for easy browsing and added accessibility. Customers can view, download, print, and save either the full catalog or specific pages and sections. EXAIR products are designed to conserve compressed air and increase personnel safety in the process. Loaded with useful information.
Check out EXAIR's online catalog.

5 cost-saving design tips for CNC machining

Make sure your parts meet expectations the first time around. Xometry's director of application engineering, Greg Paulsen, presents five expert tips for cutting costs when designing custom CNC machined parts. This video covers corners and radii, designing for deep pockets, thread depths, thin walls, and more. Always excellent info from Paulsen at Xometry.
View the video.

What can you secure with a retaining ring? 20 examples

From the watch dial on your wrist to a wind turbine, no application is too small or too big for a Smalley retaining ring to secure. Light to heavy-duty loads? Carbon steel to exotic materials? No problem. See how retaining rings are used in slip clutches, bike locks, hip replacements, and even the Louvre Pyramid.
See the Smalley design applications.

Load fasteners with integrated RFID

A crane, rope, or chain may be required when something needs lifting -- plus anchoring points on the load. JW Winco offers a wide range of solutions to fasten the load securely, including: lifting eye bolts and rings (with or without rotation), eye rings with ball bearings, threaded lifting pins, shackles, lifting points for welding, and more. Some, such as the GN 581 Safety Swivel Lifting Eye Bolts, even have integrated RFID tags to clearly identify specific lifting points during wear and safety inspections and manage them digitally and without system interruption.
Learn more.

Couplings solve misalignments more precisely with targeted center designs

ALS Couplings from Miki Pulley feature a simplistic, three-piece construction and are available in three different types for more precisely handling parallel, angular, or axial misalignment applications. The key feature of this coupling design is its center element. Each of the three models has a center member that has a unique and durable material and shape. Also called a "spider," the center is designed to address and resolve the type of misalignment targeted. Ideal for unidirectional continuous movement or rapid bidirectional motion.
Learn more.

What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) technology combines electronic and mechanical functionalities into a single, 3D component. It replaces the traditional printed circuit board and opens up many new opportunities. It takes injection-molded parts and uses laser-direct structuring to etch areas of conductor structures, which are filled with a copper plating process to create very precise electronic circuits. HARTING, the technology's developer, says it's "Like a PCB, but 3D." Tons of possibilities.
View the video.

Researchers use 3D modeling to delve into what really happens with supersonic cold metal bonding

The Cold Gas Dynamic Spray (CGDS) process is very hard to predict. The CGDS deposition zone has now been 3D modeled to show the effects of temperature for the first time by Professor Tien-Chien Jen from the Univ. of Johannesburg. Here, the model predicts an orange/red "splash" of aluminum substrate just after a 5-micron copper particle has impacted it at 700 m/sec. [Credit: Hong-Shen Chen, Univ. of Johannesburg]

 

 

 

 

When a fragile surface requires a rock-hard, super-thin bonded metal coating, conventional manufacturing processes come up short. However, Cold Gas Dynamic Spray (CGDS) can do just that -- with a big caveat. CGDS is enormously versatile, but it is also very difficult to predict key aspects of the entire process. Now a temperature-based 3D model by Professor Tien-Chien Jen from the University of Johannesburg has started unlocking the mysteries of the CGDS film-growing process in the particle deposition zone.

The model is the first to connect the dots between particle impact velocity, energy transformation, and temperature rise in the particle impact zone, in three dimensions.

CGDS is already used extensively to manufacture or repair metal parts for large passenger airliners, as well as mobile technology and military equipment.

In the process, a de Laval nozzle sprays micron-sized metal particles over a short distance, typically 25 mm, at a metal or polymer surface. The particles impact the surface at speeds ranging from 300 m/sec to 800 m/sec. As a frame of reference, the speed of sound is 343 m/sec.

CGDS has the best temperature range of all industrial spraying processes in use today, and it saves energy, because no heating is added.

A manufacturing mystery
A mystery starts on the factory floor, however. If you have a 5-micron copper particle, how fast should it arrive at the deposition zone on aluminum, if you haven't used this combination before? Or you select a new metal for the particles, and a new metal for the surface: How do you even start guessing what size the particles should be, and at what speed they should impact the surface to give you a well-bonded coating?

Keep in mind, the CGDS-bonded coating should come without evaporation, crystallization, residual stresses, or other thermal damages -- some of the big reasons CGDS is used in the first place. These questions can have enormous financial implications for the manufacturing machines on the factory floor.

Physics still out
Why CGDS bonds metal particles to a substrate surface has defied understanding since its invention in the 1980s by the military, says Jen, Professor in the Department of Mechanical Engineering Science at the University of Johannesburg.

"At first, the military used CGDS to repair spare parts in the middle of nowhere. Then other industries realized you can use it on very fragile surfaces as well. You can create a new bonded surface only a few microns thick, or keep spraying until you have a 10-mm coating. Once you've filled in the cracks or holes, you can machine the part to have its exact dimensions again, because the GDS-bonded coating can be harder than the titanium or vanadium the part is made from."

The CGDS coating can be this hard because of the compressive stresses created when the particles impact the surface. The stresses increase the metal fatigue life, he says. This is similar to what happens in shot-peening, an industrial process similar to CGDS, but using "balls" a few millimeters in diameter to impact a surface.

"CGDS is used for very high-cost manufacture and repair, but there is no comprehensive, realistic model describing the physics of the entire process," says Jen.

3D with splashing
In CGDS, engineers talk about two zones. The first is the flight-zone between the spray nozzle and the surface to be sprayed. This zone was modeled by Jen in a 2005 research article in the International Journal of Heat and Mass Transfer.

The second zone is the deposition zone, where the sprayed articles impact the surface. The new 3D model describes this zone.

Previous two-dimensional models have attempted to solve the puzzle around CGDS bonding, but these have a severe limitation. When you extend a 2D model to 3D, you end up with a "horizontal cylinder" descending toward the surface being sprayed.

"Unfortunately, a descending cylinder cannot model realistically enough what happens to discrete ball-shaped particles 'splashing' down in the substrate surface," says Jen.

As industry knows, the speed (velocity) the particle arrives at the substrate is critical. Too slow, and it will just bounce off. Too fast, and it may pass like a bullet through a thin substrate.

The new model animates in 3D a single spherical particle "falling down" into the substrate metal. The substrate "splashes up," and then the particle and substrate bond. The substrate "splashing" looks like milk splashing up when something falls into the cat's bowl. This is called "jetting behavior" in industry, says Jen.

Cold metal, temperature rise
The model uses several parameters describing the nature of the particle and the surface: density, thermal conductivity, specific heat, melting point, elastic modulus, Poisson's ratio, Johnson-Cook plasticity, and Johnson-Cook damage.

It is the first to predict in 3D how the average temperature of the particle impact zone will rise and subside, depending on the size and impact velocity of the particle. The model was published in the Journal of Thermal Spray Technology.

Just fast enough to melt
"For this 3D model, we went with the hypothesis that a metal particle has to bond with the substrate at 60 percent of its melting temperature to create a strong new surface without damaging the substrate," says Professor Jen.

As an example, copper (Cu) has a melting temperature of 1,083 C, and 60 percent of that is 650 C. So the hypothesis says that a 5-micron copper particle impacting an aluminum substrate surface will have to be fast enough so that the average impact zone temperature goes up to at least 650 C, and not much more, for good bonding to occur. According to the model, that critical impact velocity range is between 700 and 800 m/sec.

Supersonic energy transformation
When a copper particle travels at a supersonic speed and hits an aluminum surface, its moving (kinetic) energy is converted into heat (thermal) energy, says Prof Jen. This depends on the impact speed of the particle.

"The heat makes the particle and the impact zone 'soft and sticky,' similar to melted cheese. The particle changes into a 'soft blob' that fills in the 'impact crater' in the substrate surface. At the same time, friction develops between the blob and the crater surface, which is critical to the bonding process," he says.

"The friction 'grabs' the blob, and it sinks into the substrate surface. As the blob sinks down, the molten substrate around the particle 'splashes up' in typical jetting behavior. When the jetting settles down, the bond between particle and surface is completed," says Jen.

Model vs. the real world
The model, though limited, holds up in experimental results with copper particles sprayed onto an aluminum surface.

"When the impact velocity is within the range predicted by the model for a particle size, sufficient bonding temperature is reached and a strong CGDS coating is created. As an example, we set up our CGDS equipment in the laboratory for copper particles with an average size of 5 micron, carried by nitrogen, and impact velocity in the range of 700 to 800 meters per second deposited downwards on aluminum.

"The model predicts that at about 750 meters per second impact velocity, the critical bonding temperature of 650 degrees Celsius will be attained in the particle impact zone. In line with that prediction, we obtained excellent CGDS bonded coatings," he says.

"However, as also predicted by the model, we found with our laboratory setup that when the particle impact velocity is not within the critical range, insufficient bonding temperature is reached. This can result in poor surface coating with loosened powders and scrapping surface, which don't meet manufacturing quality standards," says Jen.

Grand challenge remains
The single-particle single-layer 3D model will be extended into a multi-particle, multi-layer model in follow-up projects.

Says Jen: "This 3D model is the first to describe how the temperature of the impact zone influences particle deposition. However, realistically modeling the deposition zone in CGDS remains a grand challenge to solve. In real-world conditions, particles are not of uniform size or shape, and travel at different velocities and angles. So a more complete model will have to accommodate ranges, or distributions, of all of these parameters."

Source: University of Johannesburg

Published April 2018

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