hpt 2025-#3

cover story Mastering

cover story Mastering titanium drilling: Mikron Tool’s advanced solutions Mikron Tool embodies the taste for precision typically seen in Swiss manufacturing and Swiss made products. These tools – renowned as “Crazy Tools” for their exceptional performance – are tailored to meet the demanding expectations of high-end, high-precision industries such as medical and aerospace. By combining state-of-the-art technology with an unwavering commitment to quality, Mikron Tool ensures its products are the perfect match to the unique challenges of these industries. To meet these demands the tools feature the smallest sizes, with a strong emphasis for the machining of materials typical in these industries such as titanium and its alloys. Drilling titanium, a material prized for its high strengthto-weight ratio and corrosion resistance, presents considerable challenges due to its unique properties. Its low thermal conductivity means heat generated during drilling concentrates in the cutting area, leading to rapid wear and potential tool breakage. Titanium’s inherent ductility makes chip formation challenging. Without proper chip formation, titanium chips can form chip ribbons or nests that become hard to evacuate. Especially when drilling more than three times diameter, those long, stringy chips can clog the drill flutes and hinder the drilling process. It can very quickly get challenging, and often there is little or no time to intervene: by the time the ribbons show up, it is too late. Furthermore, titanium’s tendency to form built-up edges and its viscoplasticity can cause material adhesion, affecting hole quality and process reliability. The varying properties between pure titanium and its alloys also demand highly specialized tooling. One example of Mikron Tool’s unique technology to overcome the challenges of drilling titanium is the innovative cooling concept engineered to prevent chip jamming and to avoid excessive thermal loads. Specially designed cooling channels with a very large cross-section guide massive amounts of cooling lubricant to the drill tip to avoid excessive thermal loads on the cutting edges. The patented special shape of the cooling channels allows up to four times more coolant flow (compared to conventional cooling channels) at the same pressure. At the same time, the massive coolant jet flushes the chips through the flutes and prevents any form of chip jamming. Mikron Tool’s new CrazyDrill Cool Titanium drills feature a specially designed chamber, called “Powerchamber”, which additionally guarantees sufficiently strong coolant flow for smaller diameters of up to 0 2.95 mm. 6 no. 3, September 2025

cover story Tool wear and chipping are significant issues when drilling titanium alloys due to their high tensile strength and low thermal conductivity. The intense cutting forces required to penetrate titanium lead to rapid tool wear, especially at the cutting edge corners. The material’s tendency to retain heat magnifies this problem, causing localized thermal stress that accelerates wear and increases the risk of tool chipping. Additionally, titanium’s reactive nature can lead to material adhesion on the tool, further contributing to wear and chipping. To mitigate these issues it is highly recommended to use carbide drills with specialized coatings to enhance wear resistance and prolong tool life. Drills with positive rake angles reduce cutting forces and help in smooth chip removal, minimizing tool wear. Cutting speeds and feeds should be finetuned to balance tool life and machining efficiency. Finally, ensuring effective cooling is one of the most essential strategies for enhancing tool performance and longevity. At the center of the drill tip the cutting speed is effec - tively equal to zero. This creates high axial forces, which have a great influence on process reliability, especially when drilling workpieces with thin walls. The design of the tip cutting geometry is therefore crucial to reduce the axial forces. A traditional tip cutting geometry with a wide drill core generates high axial forces, which can lead to deformation during the drilling process on unstable, thin-walled workpieces. In addition, excessive axial force can cause undesirable deflection of the drill. Mikron Tool designed the new CrazyDrill Titanium TK/TN with a specifically designed web thinning. In combination with a cutting geometry engineered to machine titanium materials, the axial forces are significantly reduced. This results in a force reduction of 25 % to 45 %. EMO 2025, hall 3, booth G03 and hall 17, booth A48 further information: www.mikrontool.com no. 3, September 2025 7