High-feed mills suit aerospace materials

To enhance milling performance on ISO S materials, Sandvik Coromant is introducing a new series of end mills. CoroMill Plura HFS (High-Feed Side milling) cutters are intended for use on workpieces made from titanium and nickel-based alloys, bringing benefits to both aerospace engine and frame applications.

Sandvik Coromant’s CoroMill Plura HFS range comprises two end-mill families for titanium alloys, and one for nickel alloys. As chip evacuation and heat are specific challenges when machining titanium, the company has developed a solid version for normal chip evacuation conditions, and another featuring internal coolant and a new cooling booster (patent pending) for swarf and temperature control.
The end mills for titanium are available in GC1745 grade, which is based on a fine-grained (sub-micron) cemented-carbide substrate. A new multi-layer coating that contains silicon is said to provide good wear resistance and low thermal conductivity. The geometry of the cutters is based on a six-flute concept with no centre cut and uneven tooth pitch. Additionally, the core dimension has been optimised for higher stiffness in titanium alloys, while the corner radius, rake angle and relief are all designed specifically for machining ISO S materials.
For nickel alloys, grade GC1710 is deployed, which features a wear-resistant, fine-grained substrate designed to withstand high working loads when machining hard, highly adhesive, work-hardened materials such as aged Inconel 718. Here, a new coating produced with HIPIMS (high power impulse magnetron sputtering) technology offers adhesion-reducing properties to avoid the formation of BUE (built-up edge) and increase tool life.
For further information www.sandvik.coromant.com

Shoulder mills for challenging materials

Designed to boost productivity when milling challenging materials, Industrial Tooling Corporation (ITC) has launched the new VSM17 line of shoulder-milling tools from Widia into the UK market.

The 90° shoulder milling platform offers aggressive ramping angles of up to 8.8° with guided internal coolant supply; features that combine to help elevate material removal rates and chip clearance. The steel VSM17 tool bodies are available with screw-on, Weldon and cylindrical end mills from 25 to 40 mm diameter (with regular and long shanks), shell mills from 40 to 160 mm, and the M4000 cartridge milling system in diameters from 125 to 315 mm. The various tool bodies incorporate an optimised chip gash that is designed to optimise stability, chip removal and cutting efficiency.
This latest addition to the Widia 90° VSM series is suitable for everything from light, precision machining to medium roughing. The tool’s two-edged 16 mm inserts incorporate an embedded wiper facet for high surface finishes, an additional margin on the clearance face that strengthens the cutting edge and a positive rake design which generates a soft cutting action.
The inserts are offered in a range of grades for machining cast iron, steel, stainless steel, aluminium and a variety of additional materials. Each insert grade is offered with the option of the ALP, ML, MM and MH insert geometries. ALP is a peripheral ground geometry for the rough to finish machining of aluminium alloys, whereas ML is designated for light to finish cutting on stainless steel and titanium. MM and MH are general and heavy-duty cutting grades for a multitude of material types.
For further information www.itc-ltd.co.uk

Kennametal unveils new indexable milling grade

Kennametal says that customers have been asking for a new carbide grade to machine titanium 6Al4V at higher cutting speeds instead of having to increase feed rates or depth of cuts, which can result in greater cutting forces on the workpiece, fixture and spindle. With this in mind, the company’s latest KCSM40 grade has a cobalt binder that provides thermal fatigue resistance without sacrificing toughness. In addition to the new material substrate, Kennametal´s proprietary AlTiN/TiN coating is said to enhance wear resistance at the cutting edge.

The target cutting speed for KCSM40 in Ti6Al4V was 53 m/min, while hitting in excess of 327 cu cm/min metal removal rate for 60 minutes. According to Kennametal, not only did KCSM40 achieve this but showed the capability to mill titanium at speeds up to 85 m/ min at a lower radial depth of cut.
Recent internal testing with the new Harvi Ultra helical milling platform achieved over 100 minutes of tool life running at 47 m/min with a 0.12 mm/t chip load. Radial depth of cut was 25 mm and axial depth of cut was 76 mm. Kennametal says that the edge condition on the KCSM40 grade still looked great.
The company is also witnessing many other good results. For instance, in one face-milling operation on a hardened steel wear plate, the number of passes was reduced from 234 to just 22.
For further information www.kennametal.com

High-finish shoulder milling

According to Sumitomo Electric Hardmetal, key to the capability of the Sumi Dual Mill TSX series of higher efficiency, 90° shoulder mills is the combination of fine-carbide insert press/sintering technology with precision profile-grinding techniques. This enables the periphery ground inserts used with the new tangential cutter body design, which is available in standard, medium and fine-pitch versions, to generate high levels of surface finish.

The TSX series is based on the use of tangentially mounted carbide inserts offering a choice of chip-breakers: L for low-rigidity machine set-ups, G for general purpose operations and H where a stronger insert edge is required to support tasks such as rough, heavy interrupted and hard-steel milling, for example.
Sumitomo’s TSX shoulder mills comprise shell-type bodies between 40 and 160 mm diameter, and shank-type bodies between 16 and 160 mm diameter, to support operations such as face and shoulder milling, slot milling, and side and face-milling tasks. Two sizes of insert, each with four corners, are precision ground to accommodate 8 or 12 mm depths of cut.
A recent customer trial witnessed the milling of a workpiece made from 42CrMo4 alloy steel. Using a TSX shell cutter body combined with ACP200 grade inserts and G-type chipbreaker, the process (with coolant) was run at 270 m/min cutting speed, 0.05 mm/rev feed and 8 mm depth of cut. Not only did the Sumitomo set-up improve component wall quality, it increased the number of parts produced from 135 to 220.
For further information www.sumitomotool.com

General milling grade for steels

Dormer Pramet has launched a new milling grade for general machining applications in a variety of common engineering materials, particularly steels. Suitable for both finishing and roughing, even in unfavourable cutting conditions, the M8330 grade is said to provide a reliable and versatile option when machining either with or without coolant, in steels and cast iron. The new grade is also suitable for stainless steel, super alloys and hardened steels.

The M8330 replaces the existing 8230 grade and features a nano-layered PVD coating which is designed to offer increased resistance to thermal cracks, improved toughness and greater impact strength.
Added to more than 90 different types of existing Pramet milling inserts, M8330 is also available in a completely new range of inserts for copy milling. RCMT10 inserts offer high metal removal rates, with up to 5 mm depth of cut and strong durability. Designed to allow a high feed per tooth, RCMT10 is available in three geometries to support operations in a range of materials: geometry F is for stainless steels, super alloys and low-carbon steels; geometry M for steels and stainless steels; and geometry R for cast iron and hardened materials.
To support this addition, Dormer Pramet has expanded its current line of SRC copy-milling cutters. The SRC10 is a series of small diameter cutters available in sizes from 25 to 66 mm, and in a variety of types, including end mills, modular and shell mills. A double-negative design is deployed to provide a stable cutting action, even during roughing, making it suitable for operations such as face milling, helical interpolation, ramping, progressive plunging and high-feed cutting.
For further information www.dormerpramet.com