New developments in milling

New developments in milling
 Modern milling, as a metal cutting method, originated in the late 18th century and quickly became one of the main processing technologies. Today, it’s hard to imagine a machine shop without a milling machine. It can be seen that milling is an essential process in processing and manufacturing.

 Today, we are witnessing significant changes in the manufacturing industry that will have a profound impact on the direction of milling. These changes are driven by a variety of factors, such as increased precision in metal forming through precision casting and forging, the widespread use of 3D printing technology, the increasing use of new composites and sintered materials, and improved high-temperature alloy and titanium alloy parts. Productivity needs, as well as the automotive industry's focus on electric and hybrid vehicles, have contributed to these changes. In addition, advances in multi-axis machine tools have opened up new possibilities for precision machining of complex parts and have given rise to new cutting methods that increase productivity. In modern machining technology, a trend is to significantly reduce the milling allowance and improve the surface quality and accuracy of the workpiece.

 Therefore, the progress of milling is driven by people's demand for higher productivity, higher precision and sustainable development of milling processing. The main developments in milling processes can be summarized as follows:

 1. The focus of rapid metal removal is to improve the metal removal rate (MRR), achieving higher productivity by significantly increasing the cutting speed or feed per tooth. This is achieved through techniques such as high-speed milling (HSM) and, in roughing, high-feed milling (HFM).

 2. Precision milling can achieve higher machining accuracy.

 3. Multi-axis milling is characterized by the use of multi-axis processing machine tools to achieve complex milling processes.

 4. Adaptive milling aims to develop intelligent milling systems to adapt to changing conditions during machining.

 5. Sustainable milling aims to reduce the environmental impact of milling operations. It involves the development of environmentally friendly cutting fluids, the recycling and reuse of materials, and the use of energy-saving machine tools and milling cutters.

 The development of the above aspects is inseparable from the synergy of several key components, namely machine tools, cutting tools and computer-aided engineering (CAE) systems. For example, high-speed milling requires machine tool technology that can meet extremely high rotational speeds, as well as advanced base materials and coating technologies for milling cutters. At the same time, improving the accuracy of milling processing requires not only higher-precision tolerances of milling cutters, but also improved control systems and linear motor drives. In the case of multi-axis milling, the breakthrough lies in the addition of controllable axes of motion and the use of suitable milling cutter cutting geometries. Adaptive milling, on the other hand, combines innovations such as the use of state-of-the-art monitoring systems, highly sensitive sensors and efficient algorithms to optimize cutting data and tool paths in real time. Furthermore, advances in sustainability require energy-efficient milling methods, including the use of suitable machine tools, cutting tools and environmentally friendly cooling technologies.

 Indexable milling tools reflect advances in milling methods and feature interchangeable cutting inserts during machining.

 a) Optimizing the material of inserts is a continuous process to improve the materials of indexable milling cutter inserts, including the development of advanced carbide grades, ceramics and super-hard cutting materials.

 b) Development of coating technology: New coatings are constantly developed to improve wear resistance and heat resistance while enhancing lubricity.

 c) Use optimized geometry of milling cutters and inserts to complete milling, which can reduce cutting forces and control chip shape and chip removal direction during the milling process.

 d) Efficient use of tool insert materials, including the use of smart insert designs to provide maximum indexable cutting edges without reducing cutting performance.

 Furthermore, smart manufacturing requires the incorporation of digitalization into milling operations and milling tools. When it comes to milling tools, digital twins and suitable software applications have become “standard” in a comprehensive tool system.

 So how should tool manufacturers respond to this challenge? Which milling cutter solutions respond to emerging trends? It is often thought that the production of cutting tools is a more conservative part of metal processing, so can it respond in a timely manner to the current needs of the metal processing field? Iska's recent developments provide in-depth answers to these questions.

 The high-speed trochoidal milling method involves maintaining a constant cutting edge load along a curved tool path, thus avoiding sudden load peaks during machining. This machining method is very effective for milling deep grooves, grooves and cavities, especially when machining stability is low. In addition, trochoidal milling is particularly effective when processing difficult-to-machine materials such as hard steel or high-temperature alloys (HTSA).

 CHATTERFREE EC-E7/H7-CF is a new series of multi-edge solid carbide end mills that can be used for trochoidal milling. The series' geometric design includes variable helix angles and unequal tooth pitch to improve dynamic performance. These end mills are available in a range of cutting aspect ratios. 

Thanks to modern machine tools, aluminum parts can be milled efficiently at very high spindle speeds (up to 33,000 rpm). To meet this machining challenge, ISCAR has developed a 90° indexable milling cutter that can accommodate large inserts and a cutting depth of up to 22 mm (.870”). The tool is specially designed to prevent radial displacement of the insert caused by the high centrifugal forces generated during high-speed rotation.

Thanks to modern machine tools, aluminum parts can be milled efficiently at very high spindle speeds (up to 33,000 rpm). To meet this machining challenge, ISCAR has developed a 90° indexable milling cutter that can accommodate large inserts and a cutting depth of up to 22 mm (.870”). The tool is specially designed to prevent radial displacement of the insert caused by the high centrifugal forces generated during high-speed rotation.

Advances in multi-axis machine tools and CAD/CAM systems have led to the use of curved and drum milling cutters for precision milling of complex shapes with minimal machining allowances. This product range includes three different constructions: solid carbide, MULTI-MASTER exchangeable heads and single insert designs

When milling high-temperature alloys (HTSA), the use of ceramic grades can significantly increase cutting speeds. Cutting speeds can reach 1000m/min (3300 sfm). ISCAR's latest ceramic tools include solid ceramic end mills and indexable milling cutters with double-sided round ceramic inserts. The double-sided inserts are designed to maximize the use of ceramic grades such as "black" ceramics, whisker-reinforced ceramics and SiAlON (a silicon nitride-based ceramic).

These examples perfectly illustrate the main development directions of milling tools. New needs require new solutions to meet them, and these new challenges will drive the exploration of innovative tool designs.