skip to Main Content
Machining The Super Material—Titanium

Machining The Super Material—Titanium

Anyone who has machined the super-material titanium knows it can be something of a trouble-maker if not handled properly. Chips do not break, heat does not dissipate, edges build up – these are the difficulties that titanium creates when machined. On the uptick, titanium has outstanding properties that make it a hot favourite in aviation, motor racing and medical engineering, so it is well worthwhile amassing some know-how beforehand. Article by ARNO Werkzeuge.

The history books make no mention whether the chemist Heinrich Klapproth named the element titanium after the deity of Greek mythology because of its divine properties. The fact is, however, its properties make it into a super-material. Titanium combines properties such as an extremely high tensile strength, light weight and outstanding corrosion resistance – but these cause conflicts with other materials or alloys. As titanium is also anti-magnetic, biocompatible and resistant even to the most aggressive media, the expensive material is gaining favour in an increasingly greater number of sectors and applications. Engineers at Bugatti know this very well since they use a lot of titanium in their supercars.

Titanium is Expensive So Scrap Must Be Avoided

Anyone wanting to machine titanium must first invest a lot of money as it costs about three to five times more than tool steel. So, it is obvious you would want to avoid scrap. But the choice of material alone is not enough. The proper tools are needed to machine the precision turned parts made of titanium required in the aerospace industry, chemical industry, vehicle construction or medical technology. This is the only way to bring even obstinate titanium alloys into the desired shape.

These are the special attributes of titanium that make life hard for tools: 

  • Extremely poor thermal conductivity
  • Non breaking chips
  • Extreme tendency to stick to the flute
  • Low modulus of elasticity
    (Ti6Al4V = 110 kN/mm2, steel Ck45 = 210 kN/mm2) 

As only the very few are likely to find themselves in the awkward situation of producing titanium screws for the 1500 hp Bugatti Chiron super sports car, let’s first look at the production of a threaded shaft with recess made of the common titanium alloy Ti6Al4V Grade 5/23 as used in medical technology. Its tensile strength of Rm = 990 N/mm2, yield stress of Re = 880 N/mm2, hardness HV between 330 and 380 and elongation factor A5D of about 18 percent make it ideal for use in implants in medical technology and for applications in aviation (3.7164) or industry (3.7165). The alloy contains six percent aluminium, four percent vanadium and ELI (extra low interstitials), giving it very good biocompatibility and practically no known allergic reactions.

Heat Must Be Extracted From the Cutting Zone

The requirements call for a high surface quality, reproducible process reliability and controlled chip evacuation – all this including short process times and possibly a high chip removal rate. If you expect most of the heat generated during turning is normally dissipated through the chip, you are in for your first big surprise: titanium is a very poor conductor of heat and heat is not dissipated when the chip is removed from the cutting zone. In addition, at temperatures of over 1200 deg C prevailing in the cutting zone, the cutting tool is very quick to “burn”. Immediate help is provided by introducing measures such as feeding coolant directly to the cutting zone, reducing cutting force by using a sharp flute and adapting the cutting speed to the process.

 

For other exclusive articles, visit www.equipment-news.com.

 

Check these articles out:

ZEISS Partners Microsoft To Accelerate Cloud Solutions For Efficient Manufacturing

Tool Craft For Aircraft

Laser Process Measuring Technology for Precision Machining

Miniaturisation In Clamping Technology Thanks To Additive Manufacturing

3D Systems’ Metal AM Solutions Selected By Raytheon Technologies And CCDC Army Research Laboratory For Novel Thermal Application

Hexagon And Plex Systems Announce Partnership To Deliver Smart Manufacturing Solutions

 

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter

 

 

A New Approach To Aircraft Titanium Machining

A New Approach To Aircraft Titanium Machining

Makino introduces a new approach to overcome the challenges in titanium parts machining for aerospace manufacturers. 

The appeal of Titanium is no mystery. Its material properties of toughness, strength, corrosion resistance, thermal stability and light weight are highly beneficial to the construction of today’s aircraft.

However, aerospace manufacturers producing titanium parts quickly discover the difficulty these material properties present during the machining process. The combination of titanium’s poor thermal conductivity, strong alloying tendency and chemical reactivity with cutting tools are a detriment to tool life, metal-removal rates and ultimately the manufacturer’s profit margin.

Producing titanium parts efficiently requires a delicate balance between productivity and profitability. However, in standard machining practices these two factors share an inverse relationship, meaning greater productivity can come at a higher cost due to rapid tool degradation, while the desire to increase profit margins by extending tool life may result in decreased metal-removal rates and extended cycle times.

Overcoming this issue requires a new approach by Makino in which all components of the machining process are developed and integrated specific to the material’s unique challenges—requiring a reassessment of even the most basic machine tool design considerations. This was the concept for the new T-Series 5-axis horizontal machining centers with ADVANTiGE technologies, and the results speak for themselves—four times the productivity and double the tool life.

Changing the Rules

In the past, and even in some shops today, titanium is typically machined using multi-spindle gantries and machines with geared head spindles. While these technologies have been effective, the growing complexity of part geometries and required accuracies have brought forth several limitations, including machine and spindle vibration, poor chip removal and limited tooling options.

In support of the aerospace industry’s demand for titanium, Makino established a Global Titanium Research and Development Center, managed by a select group of engineers with knowledge and experience around titanium in both academic and industrial backgrounds. 

The company’s breakthrough, ADVANTiGE, is a comprehensive set of technologies that includes an extra-rigid machine construction, Active Damping System, high-pressure, high-flow coolant system, Coolant Microsizer System and an Autonomic Spindle Technology.  Each technology is designed specifically for the titanium machining process, providing dramatic improvements in both tool life and productivity.

Creating a Rigid Platform

Rigidity of a machine tool is one of the single most important components in titanium machining, heavily influencing the equipment’s stable cutting parameters. 

Machines designed with low rigidity offer limited stable cutting zones, dramatically reducing the maximum level of productivity that can be achieved across all spindle speeds. To increase the productivity of a low-rigidity machine, manufacturers have only one option: taking lighter cuts and increasing spindle speeds, resulting in dramatic reductions in tool life.

To continue reading this article, head on over to our Ebook!

 

Check these articles out:

3D printing And Titanium — A Life-Changing Combination

Machining Aluminium Components Economically

Iscar: High Speed Spindle

Hexagon Enhances Its Smart Manufacturing Solutions Portfolio With Acquisition Of D.P. Technology Corp

Sandvik Coromant Expands Digital Machining Division In Southeast Asia And Oceania

EMO MILANO 2021: Meet “The Magic World Of Metalworking” In October 2021

Universal Robots Reaches Industry Milestone With 50,000 Collaborative Robots Sold

 

For other exclusive articles, visit www.equipment-news.com.

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter

 

 

 

Special Tools For Difficult Recesses

Special Tools For Difficult Recesses

While machining of titanium alloys no longer poses any major challenges for experienced machinists—when machining operations are straightforward—intricate sensor component designs made from titanium call for an appropriate tool design and an intelligent machining strategy. Article by Paul Horn GmbH.

“We have been relying on tools from Paul Horn GmbH for more than  30 years. The solution to our latest problem has once again reminded us of why,” explains Roland Burghart, who is in charge of turning at the Donaueschingen plant of Sick Stegmann GmbH. The problem related to the creation of axial recesses in intricate sensor components made from titanium.

Horn solved the task through a combination of measures, which included various special versions of its Mini system. Working in conjunction with Horn technical consultant Karl Schonhardt, the Horn designers devised a cut distribution for the difficult machining task.

The workpieces are installed inside highly sensitive gas flow measurement sensors. At the heart of these measuring units lie the oscillating transducers. The sensors are used, for example, in gas pipelines, for measuring flare gas, for vapour flow measurement, as well as in biogas plants. Sensor technology from Sick is intended to protect people from accidents, avoid damage to the environment, and supply accurate data. For this reason, the company demands a high standard of quality from its products. This starts with the individual parts and components. Tight tolerances, high surface quality, and difficult to machine materials are all part of everyday life for the Sick employees working in the area of CNC manufacturing. 

To ensure high corrosion resistance, the engineers from Sick selected the titanium alloy Ti 6Al-4V (Grade 5) for the transducers. This alloy accounts for approximately 50 percent of worldwide demand for titanium. And that is because it offers a good balance between high strength and low density. The mechanical properties of this alloy are superior to those of pure titanium. One of the problems it poses during machining is that it has a tendency to work harden. When the friction becomes excessive due to the feed rate of the cutting edge being too low, work hardening of the material is induced. This shortens the life of the tools dramatically. When turning and milling titanium, it is vital to have sharp cutting edges, the right cutting parameters, and the appropriate tool coating in order for the machining of this material to be productive.

To continue reading this article, head on over to our Ebook!

 

For other exclusive articles, visit www.equipment-news.com.

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter

 

 

3D Printing And Titanium — A Life-Changing Combination

3D printing And Titanium — A Life-Changing Combination

3D printing is delivering customisation options that make it possible to create almost any shape using additive manufacturing (AM) technology. In fact, the possibilities of 3D printing are so game-changing, it is even possible to create carbon copies of our own skulls. Sandvik’s additive manufacturing and metal powder specialists are exploring the potential of AM in the medical field, and are preparing for the future of medical implants.

Life-threatening accidents, vertebral damage, chronic osteopathic conditions and side-effects from medical treatment can all cause irreparable damage to patients. The consequences can be painful, debilitating and even fatal, so we must develop solutions to help the human body overcome challenges, enhance the healing process and improve patient prognosis. Medical implant technology has developed vastly over the years, and one of manufacturing’s most disruptive technologies is set to transform the way we treat patients.

Medical implant developers require a manufacturing technology that delivers speed, individualisation and the ability to produce complex designs. 3D printing, paired with bio-compatible materials like titanium, is demonstrating its evident potential as the medical industry’s manufacturing technology of choice for life-changing solutions.

In the past, surgeons used metal mesh to replace areas of the body such as skull bones, which tended to be weak and lacked precision. 3D printing eliminates these flaws because it uses medical imaging to create a customised implant, shaped exactly according to the individual’s anatomical data. This means that the patient can be fitted with an exact match to replace the lost or damaged area of the skull.

In Sandviken, Sweden, lies one of the world’s most cutting-edge titanium powder plants. At the plant, Sandvik’s experts are unlocking the potential of 3D printed titanium devices for the medical industry. “Titanium, 3D printing and the medical sector are the perfect match,” explains Harald Kissel, R&D Manager at Sandvik Additive Manufacturing.

“Titanium has excellent properties and is one of few metals accepted by the human body, while 3D printing can rapidly deliver bespoke results for an industry where acting quickly could be the difference between life and death.”

In addition to titanium’s material benefits, AM can help overcome some of the challenges when producing medical implants and prosthetics. Typically, the process of being fit for a prosthesis involves several visits to create a device that fits a patient and their needs. As a result, the time between a patient’s life-changing surgery and them receiving their device can be painstakingly slow.

“If a patient undergoes a serious accident, one that destroys areas such as the skull or spine beyond repair, they simply do not have time to spare to ensure their reconstructive devices fit correctly. Instead, they’re given solutions that work, but aren’t tailored to their bodies,” Kissel explained.

“Long waiting times and a lack of customisation can really impact how a patient feels after they’ve undergone a life-changing event or procedure. Even in 2020, there are still prosthetic patients using devices that do not move, or are simply just hooks.”

“Using computer tomography, it is now possible to optimise designs that simply cannot be produced using other manufacturing methods. What’s more, we can make our designs lighter, with less material waste and in shorter lead times. Patients could receive a perfectly matching device, in less time and using a high-performing, lightweight material.”

In summer 2020, Sandvik’s specialist powder plant was awarded the ISO 13485:2016 medical certification for its Osprey titanium powders, positioning its highly automated production process at the forefront of medical device development. As AM disrupts many areas of manufacturing, it’s clear that its potential in the medical sector will be life changing.

Sandvik is also part of one of the most ground-breaking research projects within the medical segment to date, contributing with its extensive material expertise. The Swiss M4M Center in Switzerland is a public-private partnership initiated by the Swiss government, aiming to evolve medical 3D printing to a level where patient-specific, innovative implants can be developed and manufactured quickly and cost-effectively.

“The Swiss M4M Center is intended to build up and certify a complete end-to-end production line for medical applications, like implants. Being able to facilitate this initiative through the unique material knowledge that is found within Sandvik is an empowering experience. Joining forces with an array of experts to reinvent the future of medical devices as well as the lives of thousands of people — is an experience out of the ordinary.”

For other exclusive articles, visit www.equipment-news.com.

 

WANT MORE INSIDER NEWS? SUBSCRIBE TO OUR DIGITAL MAGAZINE NOW!

FOLLOW US ON: LinkedIn, Facebook, Twitter

 

 

  • 1
  • 2
Back To Top