The U.S. needs more of this critical metal — and China owns 80% of its

The tooling industry is constantly reinventing itself to respond to customer needs, CemeCon’s Lake acknowledged. “So then, how do our coatings need to align to help give the best product? It’s not just a coating, it’s not just geometry, and it’s not just carbide. It’s all three of those things working together that make a tool successful.”

CemeCon Inc., Big Flats, N.Y., is fielding more requests for application-specific coatings based on customer needs. And the trend is expected to increase in coming years.

On top of these benefits, the company has gone from four operations—two rough cuts and two grinding passes—on two machines to a rough and finish cut on one machine. One setup is all that is needed.

Opening to rave reviewsTiger.tec products, which include face mills, end mills, indexable drills, slotting cutters, copy mills, boring tools, and turning inserts, have only been on the market about a year. But shops using them are reporting good results. Such is the case for a pump-manufacturing facility in North Carolina.

Finally, out of left field comes an interesting idea for improving workstation efficiency: color-coating production tools. For this, Fabricio suggested the Baliq Unique coatings line with approximately 30 different colors available, “If you have a dimensionally similar tool or left- and right-hand tools—traditionally this is a point of error—you could use color to aid operators.”

"Aluminum oxide has a low chemical solubility and low diffusion against cutting forces and the chips flowing over it," says Patrick Nehls, product manager of milling and drilling for Walter Waukesha. The end result is improved chip load for freer cutting and less wear and tear on the cutting edges, he explains.

“We are talking about high-temp alloys like titanium and Inconel, which is nothing new,” Fabricio said. “But we also see a tendency on the machining sites to apply more sophisticated toolpath strategies to maximize MRR (metal removal rate).

Such initiatives can have a broad impact and need to be adopted across the global manufacturing industry, advised Inka Harrand, product management coating service cutting inserts for CemeCon AG in Germany. She said all manufacturers are obligated to design production processes in an economically and ecologically sensible manner.

Barlow amplified this point. “What’s really changed in the CVD diamond world is its continued growth and importance to commercial aerospace,” he said, noting the company can provide from three to 18-micron thick coatings—with applications at each of those extremes, depending on tool type. Applications for diamond coatings are expected to expand for “graphites, ceramics, carbon fiber, the high silicon, non-ferrous materials, and especially high-silicon aluminum primarily used in commercial aerospace.”

The high-strength materials, harsh environments, and demanding requirements in aerospace and defense applications are well documented.

While Oerlikon typically avoids proprietary coatings, it doesn’t rule them out. One example is a coating developed and cyclically improved for an aerospace customer, which Fabricio described as “a coating for a tailor-made geometry” with a unique edge preparation.

For example, CemeCon’s design goals remain longer tool life at higher speeds, a more cost-effective tool design, and less waste, i.e., finer cuts, according to Manfred Weigand, product management for the company’s coating service-round tools. What’s changed, he noted, are manufacturing parameters, such as advances in CAD/CAM, which have led to refinements in tool geometry and coatings. This increases the importance for coatings to be optimally adapted to tool geometry.

Given supply chain fragility, changes are inevitable but not universal, and some are affected more than others. No industry is immune, yet the tooling sector and its requirement for high-quality metals, rare earths, and exotic and conventional gases may be particularly exposed to supplier disruptions.

“Technology has to keep up with that demand in terms of delivering a process that’s capable of high texture,” he said, adding that Sandvik recently made a substantial investment for new mass flow controllers and supporting equipment for gas distribution into the furnace to optimize the deposition of layers of coating.

Fabricio also touted a new PVD deposition process called Baliq S3p (Scalable Pulsed Power Plasma), which is the next step in the evolution of HiPIMS processes.

“Cutting tool manufacturers have three levers at their disposal within their sustainability strategy: tool solutions, tool manufacturing, and machining strategies,” Harrand explained. “Tool coatings contribute significantly to the sustainable design of the machining process and are an indispensable building block for the cutting tool manufacturer, because they extend the product tool life and reduce the production of new (products) and the disposal or recycling of old products.”

“The more we can reduce variation, the more predictability increases for the customer in terms of performance,” he added. “When you’re a high-volume operation like we are, producing millions of inserts, if we can from a statistical standpoint reduce the amount of variability in the products and increase confidence that the customer has in the product that they’re using, it furthers customer loyalty, improves relationships, and delivers a better overall customer experience.”

CemeCon’s Schiffers reminds us that, “In principle, all coatings extend the tool life—if they have been optimally adapted to the substrate.”

Meanwhile, Oerlikon’s 2020 acquisition of D-Coat GmbH enhanced its abilities to meet growing demands for diamond coatings. “We have incorporated D-Coat’s technology and best practices for our current diamond coatings,” Fabricio said, “and we can provide a solution for the most demanding operation posed by the machining of composites you may experience.”

The pump manufacturer previously made two roughing passes on a VMC using 4-wiper-insert carbide cutting tools. It then transferred the part to a surface grinder to rough and finish grind both sides to obtain the required flatness, parallelism, and surface finish. Total machining time per cover was 32 min.

Oerlikon extends its sustainability efforts beyond minimizing gases and chemicals used in multiple processes for environmental and employee safety to using hybrid and electric vehicles with more efficient routing of customer delivery and pickup. Added Fabricio, “Even the chemicals that we use, we are always researching for something that is less aggressive or that is more environmentally friendly to be sure that we are in sync with global expectations for companies that use this kind of technology.”

Sandvik’s new furnace, operating at ultra-low pressures, allows for more temperature variations, Johnson said, and “may improve the consistency and quality of the products that we produce.

Whether it’s Boeing, Lockheed, GE, or SpaceX, A&D manufacturers need enhanced tool life for extreme materials. For instance, Inconel, a nickel and chromium alloy typically used for rocket engines, is both physically hard and hard to machine. The right tools with proper geometries are critical in failure prevention and efficient machining. As a result, toolmakers committed to this market are equally dedicated to premium solutions with high performance, high speeds, and feed rates for efficiency.

As a result, coating recipes can be adapted to the requirements of the market, tool material, and tool design as needed, including the customer’s own, Schiffers said.

The cast iron submersible pump has two covers. The front cover, in particular, is a challenge because the company has to maintain parallelism with the bottom of the pocket in correlation with the mounting face of the cover itself. The job also requires a flatness of less than five-tenths over the entire surface—roughly an 8-in. diameter—and a surface finish of 32 Ra or better.

Sandvik’s Westminster plant has invested in ethanol distillation over the last two years, and has “100 percent circularity” of the chemical, Johnson said. “We never have to purchase ethanol again, which gives us independence from global sources, saving cost and improving sustainability.”

Results show that Baliq coatings will minimize deposition of droplets, making the coating, or the coating surface, smoother, according to the company. This reduces friction and therefore reduces the wear, generating less heat, Fabricio explained. The reduced temperature will deliver either a longer tool life or it could be re-equalized, increasing the SFM to reduce the cycle time, he added.

Even pre-pandemic, developing strategies for sustainability within the tooling industry was increasingly consequential. Citing Sandvik’s motto of “People, Planet and Profit,” Johnson said the planet portion focuses on the company’s green factory initiatives, particularly the use of chemicals. This includes scrubbing exhaust gases as well as lessening environmental footprints, energy consumption, and water consumption.

“(It’s) a conversation we have with customers now, due to different coating solutions we offer, and it’s not something we did even four or five years ago,” said CemeCon President Jeff Barlow. “Previously, a concern about edge prep was really for thicker coatings on inserts, and that’s really where it ended. Now it’s expanded to round tools.”

The company uses Tiger.tec in several applications. However, its greatest success to date has been face milling a fixed-pocket gear pump. The company is not only cutting much faster than it was previously, but it is also extending tool life and increasing part accuracy.

This has led to ongoing advances in tooling technologies, albeit mostly incremental, which in turn drives similar innovations among coating suppliers. In addition, the importance of improved quality and strong relationships has renewed interest in sustainability and accelerated internal innovation. Another trend: greater customization.

Tool coatings, the recipes and how they are deposited, are dedicated to extending tool life regardless of speed or geometry, stressed Christoph Schiffers, product management for CemeCon’s coating equipment. “In general, the desire to reduce CO₂ emissions greatly stimulates the innovation process with regard to new products and processes on the market,” he said. “In this context, the CemeCon HiPIMS (high-power-pulsed-magnetron-sputtering) technology makes it possible to deposit almost every element of the periodic table of elements onto a substrate.”

Johnson continued: “And, as always, there is high focus on quality. Over the last three to five years, I would say there’s an increased pressure on cost reduction and cost productivity. And that really challenges us to constantly improve our production process, not only from a resource utilization standpoint, but also including labor, raw materials, and within day-to-day operations.”

“Certainly, there is still standard tooling—that’s kind of the bedrock of the tooling industry—but tool manufacturers are getting requests for unique geometries for special applications,” said Sales Manager Ryan Lake. “End users are coming out with new alloys, new challenges. And we must determine how to continue to optimize our products for those special (applications).”

The math is simple, he points out. While tool cost is roughly 4% of total manufacturing expense per piece, increasing cutting data by 20% cuts overall costs by 15%. "Increasing cutting data means we want to run faster and run longer between insert changes," he explains. "And shops get both these benefits with Tiger.tec."

The black aluminum-oxide top coating protects the inserts from tribochemical wear. This coating allows the inserts to run at high cutting speeds and feeds and greatly extends tool life over comparable tools, reports the company.

The Tiger.tec inserts start with a tungsten-carbide substrate, onto which goes a titanium-nitride coating that acts as a bonding layer and eta-phase barrier. Next, Walter applies a titaniumcarbonitride layer, followed by an aluminum-oxide one. The aluminum-oxide layer forms an intermediate layer with the titanium carbonitride. The intermediate layer is of a lattice composition, which produces an incredibly strong connection between the coating layers.

While CemeCon tends to offer a selection of standard products, the company makes exceptions for equipment sales. “We can make changes, different coatings, different combinations, different edge preps. We offer (those customers) a solution to their problem through equipment sales,” Lake said.

Ben Johnson, inserts production manager of Sandvik Coromant’s Westminster, S.C., plant, sees the market switching from chemical vapor deposition (CVD) to physical vapor deposition (PVD) and then a reverse back due to improvements in CVD and changes in oxide coatings. As a result, he said, Sandvik is “significantly investing in r&d to develop equipment that gives us a competitive advantage where we can develop our own coatings.”

CemeCon’s North American operations can, depending on tool type, provide coating thicknesses of one to 12 microns. Meanwhile, edge preparation is becoming increasingly important.

"The two halves of the pump are sealed with an O-ring, so finish is critical to keep the pump from leaking," says the company's senior manufacturing engineer.

Walter applies the next layer, a titaniumnitride coating, to the periphery of the inserts. This golden "indicating" coating simplifies wear detection because operators immediately see wear on cutting edges. "This helps operators tremendously," says Nehls. "It's often dark inside a machine, making it hard to check tools. With the golden area on the Tiger.tec inserts, operators can easily spot wear."

"With parts that thin," explains the engineer, "we get a lot of part flexing, so we're still grinding the rear cover." Even so, the Tiger.tec tool has greatly increased production of the part. According to the engineer, "Tiger.tec has cut the cycle time 40% on the grinding operation because we've gone from grinding ten-thousandths per side to just three-thousandths."

Plans have changed recently, he said, to factor in the materials being machined, and the thickness and composition of the coating. Customers want to know what type of edge preparation is needed on a drill or end mill “to make the coating and tool really shine.”

A pump manufacturer reports that Tiger.tec inserts cut at speeds and feeds up to 4 3 faster than its previous tooling.

While specific challenges, and opportunities continue to evolve, the need for innovation remains constant. This includes demands for better performance, longer tool life, and improved manufacturing techniques.

What sets Tiger.tec inserts apart from other coated carbide inserts is a black aluminum-oxide coating that provides wear resistance teamed with a golden titanium-nitride coating that indicates wear.

But now such requirements are spreading across other markets, such as automotive and energy, noted Osny Fabricio, head of cutting tools for Liechtenstein-based Oerlikon Balzers Ltd.

“In parallel,” he continued, “the toolmakers can now offer more complex geometries while enhancing the tool performance due to the number of flutes, optimized helix angles, and better chip evacuation. And as the market is moving in that direction, the PVD coatings are moving in the same direction, but at a higher speed, while offering a variety of high-performance premium solutions, with consistency and quality.”

First up is a newly developed type of CVD furnace being deployed to select production units, according to Johnson. “It utilizes ultra-low pressure and will provide new capabilities, especially for the demand that we’ve seen with texture coating in CVD,” he continued.

Along with the switch to single-wiper Tiger.tec face mills, the company also moved its cover machining to an HMC equipped with new fixturing. The HMC has two advantages over the VMC in this operation: better positioning tolerance and higher machine capacity. But the Tiger.tec tools are the real story, says the manufacturing engineer. Not only do they cut at speeds and feeds up to 4 3 faster than the previous tooling, their tool life is up to 3 3 longer.

Fabricio echoed this sentiment: “Customers expect not just performance, but also consistency. Consistency is probably even more important than performance, as they need to be sure that the tool will support their demanding applications without failing while maintaining consistent surface quality. They must know that specific PVD coating, that tool geometry, will deliver the same results day in and day out. So, consistency, I would say, is one of the major points for today’s demanding markets and customers.”

Besides the front cover, the company also rough cuts the rear cover using the Tiger.tec face mills. However, the grinding step can't be skipped in this application. That's because the cover is thin — about 1/8-in. thick—with two channels running the length of the part.

The real cost Obviously, Tiger. tec's performance impacts the bottom line when it comes to per-piece productivity. "First of all, we're seeing tool-life improvements of 50%, 75%, and even more," reports Nehls. "And the inserts are also improving cutting performance and profitability for our customers."

CemeCon is a pioneer of HiPIMS and offers this PVD variation as a contract coater, as well as turnkey systems. The launch of HiPIMS in 2016 was a game changer, according to Lake. “The coating came out much denser and we were increasing hardness and toughness properties to levels that people had not seen before,” he said, adding this spurred growth in HiPIMS worldwide, both in coating service and technology sales. Both Lake and Barlow view HiPIMS as the first expansion of coating technology possibly in decades.

The company had been using small-diameter roughing and finishing mills, but it found these tools inadequate for the job at hand. But Tiger.tec has improved chip load, maximizing both machine and cutter performance. The tools also helped with another problem—machine capacity. With its previous setup, the pump manufacturer could only produce 8 to 10 pumps/day.

Product offerings, including coating combinations, should be driven by customer demand, he asserted. “It’s listening to the customers and saying, this is what we need to do in this circumstance.”

Another use of coating color would be to associate the tool’s color with a group of workpiece materials. For example, Fabricio said, blue for steel, yellow for stainless steel, and red for cast iron. “Imagine that you can have a drill or end mill or insert and just by the color eliminate the need for any kind of cutting guide, manual, or catalog for guidance, and only by seeing the color you know what that particular tool was developed for.”

Black and gold. Sure, it's a striking color combination for a cutting tool insert. But beyond the flashy looks of the Tiger.tec insert is a solid performer, touts Walter Waukesha, Waukesha, Wis. The cutting tool manufacturer says the pairing of two coatings—one functional, one "indicating"—not only gives Tiger.tec tools their distinctive look but also provides performance benefits for cast iron machining and even mild-steel applications.

At Sandvik, Johnson sees “texture coatings” having a larger influence on the coating recipes for CVD in particular. “Overall coating thicknesses are typically pretty consistent with little change. However, we see more micro-layers within the overall coating thickness, and we typically see more functional layers making up the overall coating especially within the texture coating application,” Johnson said.

An extra advantage to the Tiger.tec tools is that the company could skip the grinding step for the front cover. This cut cycle times down to 15 min—more than half of what they were before. "We found that with the proper speeds and feeds, we could obtain the flatness, surface finish, and parallelism with the finish mill versus the grinding operation," says the company engineer. "We achieved our fivetenths flatness along with a 22-Ra finish and a parallelism of one to two-tenths to the bottom of the pocket. With further modifications, we're now getting about a 15-Ra finish."

The shift applies to the wide range of coating thicknesses the company offers, which it claims covers more than 80 percent of applications. “So now it becomes how do we optimize our coatings with thicknesses, pre-treatments, and cleaning to help our customers address those special needs?” Lake added.

Manufacturing speeds are increasing, and geometries for cutting titanium are getting more complex. To keep pace, Fabricio said, substrates are evolving with these new geometries, new CAD and CAM strategies for machining are introduced, and coatings are giving these tools the capability to run faster, to minimize wear, and to be able to start and finish cuts with a single tool.

But not all substrates are ferrous, nor metallic. Composites present unique challenges that, “When compared to the classic CVD process, (our) diamond coatings offer toxin-free production of extremely wear-resistant coatings with excellent thermal conductivity,” Schiffers said.