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Iscar Expands Modular Exchangeable Drilling Heads Lineup For Large Diameter Deep Drilling

Iscar Expands Modular Exchangeable Drilling Heads Lineup For Large Diameter Deep Drilling

Iscar has expanded its large diameter drilling options with the new MODUDRILL line, which features two different types of exchangeable heads: one for 33-36mm drilling and the other for 37-40mm drilling.

The MD-BODY modular body measures 400mm, is produced from high-strength steel for durability, and features a small core with central coolant hole for efficient chip evacuation. Its new patented connection withstands high torque, and its high flute helix with polished surface provides a smooth and easy chip evacuation for chips of all sizes

Carrying HFP-IQ CHAMIQDRILL solid carbide head, the MD-DFN modular head from Iscar features a robust structure with concave cutting edge design to enable drilling at high feed rates and provide IT8-IT9 hole tolerance. Its unique pocket design enables many drilling head indexes. Its special axial stopper prevents the drilling head from being extracted during retraction, while its large radial head stoppers provide high resistance to cutting forces, enabling very high cutting conditions.

The MD-DR-DH modular head carries standard SOMX indexable inserts with four cutting edges, providing an economical solution for low- to medium-feed machining.

 

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Iscar Expands Range Of Solid Carbide Milling Heads For The Aerospace Industry

Iscar Expands Range Of Solid Carbide Milling Heads For The Aerospace Industry

Iscar is expanding its MULTI-MASTER solid carbide milling heads for the aerospace industry with new interchangeable models featuring a 100° point angle. The solid carbide milling heads are suitable for chamfering, countersinking, and spot drilling applications.

The new interchangeable heads are available in four diametre sizes: 9.525mm, 12.7mm, 15.875mm, and 19.05mm. They are designed mainly for countersink holes for head cap screws according to ISO 5856, DIN EN 4072, IS 15437 standards; and for rivets according to MIL-STD-40007. The heads can also be applied for machining countersink holes for general-use 100 deg flat countersunk head machine screws, in accordance with ANSI B18.6.3-1972 standard. Most aircraft countersunk screws require a 100° angle countersink.

 

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Solid Ceramic Endmills For Machining Nickel-Based Superalloys

Solid Ceramic Endmills For Machining Nickel-Based Superalloys

Following the steady increase in the processing of nickel-based high temperature superalloys (HTSA) such as various grades of Inconel, Incoloy, and Haynes, amongst others, in the aerospace industry, and the demand to decrease production costs, ISCAR has launched solid ceramic endmills that enable increasing the cutting speed by up to 50 times when compared to carbide tools, drastically saving machining hours and reducing production costs.

Available in two configurations—E3, with three flutes for shouldering applications, and E7, with seven flutes, feed mill style for rough applications—the new endmills can also be successfully applied to productive roughing of cast iron and graphite.

The solid ceramic endmills are produced from two ceramic grades: IS6, designed specifically for machining HTSA, and IS35, intended for cutting mainly cast iron and graphite. They are available in 6mm to 20mm diametres.

 

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Tools For Large Part Manufacturing

Tools For Large Part Manufacturing

In principle, machining large parts involves the same cutting action and chip formation process as for small or mid-size parts. However, large dimensions demand a specific approach to machining, and manufacturers need to plan technological processes and choose more effective cutting tools in order to produce heavy parts that take up a great deal of space. Article by Andrei Petrilin, Technical Manager, ISCAR.

Transporting a part inside a shop floor, mounting the part in a machine tool and clamping it properly, and machine setup are major challenges. Workholding massive and large parts is not an easy task, and often requires non-standard solutions. Machining large parts involves removing a lot of material that may cause significant deformations due to unrelieved stresses. Another factor, which leads to dimensional problems, is thermal expansion caused by heat generation during cutting: the large sizes make it much more sensitive comparing with “normal-in-size” workpieces. The necessity to remove a significant material stock requires appropriate chip evacuation to prevent the chip re-cutting, which negatively affects the applied cutting tools.

The key for overcoming the difficulties lies in technology, based on effective process planning and utilizing the most suitable machine tools, optimal workholding, and minimal part relocation. Single setup machining represents an absolute ideal for machining a large part, and producers from fields such as  power generation, aerospace , railway,  die and mold making, and heavy industry make every effort to approach this ideal. And cutting tools play a meaningful role towards reaching the target.

A distinct feature of these industries is their substantial consumption of large heavy-duty tools, mostly indexable, intended for productive removal of large quantities of material, especially in rough and semi-rough machining operations.

Large part manufacturers expect the same from cutting tools as any other producer using metal cutting technologies: excellent performance, good tool life, and high reliability.  The latter two are especially essential because the large sizes lead to increased machining time, but replacing a worn tool in the middle of a pass and unpredictable breakage of the tool during cutting are totally unacceptable. In order to maximally meet the requirements of large part manufacturers, cutting tool producers provide various solutions, based on both standard and special designs.  As a leading company in the cutting tool industry, ISCAR’s years of accumulated knowhow and experience have proved to be advantageous in developing efficient solutions to these challenges.

Figure 1

Heavy-Duty Facing

It is hard to machine a large part without face milling operations. Rough and fine machining of free and bounded planes and preparing datum surfaces require various indexable face mills. ISCAR’s standard face mills possess nominal diameters up to 315 mm (12″), while special tailor-made tools might feature higher values. The inserts are mounted in face mills and vary in cutting geometry as they are intended for machining different groups of material. Significant removal of machining stock by milling is primarily an issue for the production of large parts from steel and cast iron and, slightly less, from titanium and aluminum.

ISCAR’s line of standard face mills includes many tool families for large part manufacturing. HELITANG T465 features cutters with a 65° cutting edge angle and carrying tangentially clamped inserts. The robust design enables productive machining with a depth of cut up to 19 mm (.750″). The HELIDO 890 family features 89° face mills with lay-down square double-sided inserts (Fig. 1). These efficient mills, which are truly indispensable in milling a plane near the shoulder, offer an important economic advantage: the square inserts provide eight indexable cutting edges for depth of cut up to 9 mm (.354″).

Extended Flute, Extended Effect

Indexable extended flute “long-edge” cutters are considered as winning tools for productive rough milling. In manufacturing large parts, they excel in machining deep shoulders and cavities. Extended flute cutters are also utilised in “edging” – milling wide straight edges, an operation which is common for various processes from machining slabs and ingots to primary contouring.

Figure 2

ISCAR’s line of indexable extended flute cutters varies in design configuration, integrating a shank- and arbour-type mounting method and a radial or tangential insert clamping principle. These tools work in hard cutting conditions and experience significant mechanical and thermal loading. Intensive material removal requires the appropriate volume of a tool chip gullet to ensure effective chip evacuation. The situation can be dramatically improved by applying ISCAR’s extended flute cutters carrying inserts with chip splitting geometry to divide a wide chip into small segments. As a result, cutting forces are reduced, vibrations are stabilized, and thermal problems are eased.

Although 90° tools are the most commonly used cutters, machining large parts also requires rough milling of inclined and 3D surfaces, for which ISCAR provides a family of tapered extended flute cutters with 22.5°- 75°cutting edge angles. In some cases, particularly in die and mold making, combined rough and shoulder milling is needed. The DROPMILL 3 extended flute ball nose mills were designed specifically for such applications.

Producing large-size aerospace components from hard-to-machine titanium alloys is an extremely metal-intensive process with a significant buy-to-fly ratio. The eventual weight of a part may be only 10%, or even less, of the original weight of a workpiece. The XQUAD extended flute cutter family, one of ISCAR’s newest products, is intended for high-efficiency milling of deep cavities and wide edges in titanium parts. These tools (Fig. 2) are suitable for machining with high pressure coolant supply, which significantly increases productivity and improves tool life. The tools have already proved themselves: for example, component producers have achieved a 700-1000 cm³/min (43-61 in³/min) metal removal rate (MRR) by using an 80 mm (3”) diameter XQUAD cutter.

In railway engineering, combine mills are used to ensure simultaneous machining on several areas of the part. These mills incorporate an extended cutting edge, formed by a set of successively mounted indexable inserts.

Figure 3

Productive fast runner

High efficiency machining by indexable extended flute cutters and large-diameter face mills can be likened to the work of a heavy excavator digging sand with a big bucket. The full sand bucket, operated by a powerful engine, slowly moves a large volume of waste material. At the same time, there is an alternative method for efficient excavating. Imagine a more compact track trencher with a rapidly moving digging chain. Each link of the chain removes a small volume of sand but does it fast. In metal cutting, this trencher is a high feed mill, which machines at shallow depths of cut but with a feed per tooth that is far higher than the usual rates – millimetres as opposed to tenths of millimetres.

Fast feed mills are applied mainly to rough machining of plane faces, cavities and 3D surfaces (Fig. 3). These tools are more typical in manufacturing large parts from steel and cast iron, although high feed milling (HFM) titanium and high temperature alloys is not uncommon today.

ISCAR has a wide choice of fast feed mill families, intended for cutting various materials in different applications. The “world” of ISCAR’s HFM cutters encompasses tool families in diameter ranges of up to 160 mm (6.3″) that can meet the requirements of the most demanding customer.

High feed milling requires machine tools with high-speed feed drive. Large part manufacturers often have heavy, powerful but slow machines that are not suitable for high feed face milling. For these customers, ISCAR developed moderate feed (MF) cutters.  Compared with fast feed mills, moderate feed cutters feature a higher cutting edge angle; they move slower but machine at higher depths and need more power to make them suitable for applying to heavy machines.

Large parts are often made from difficult-to-cut materials such as hard and high wear-resistant steel or cast iron. The welded part structure and the process of repairing worn parts by spraying fillers or soldering, add materials that are not easy-to-machine either. High speed milling (HSM) resolves these issues. Originally applied in die and mold making, high speed milling was developed as a productive method of milling hard steel that led to decreasing a part relocation, lessening setup, minimizing manual finish and polish, and, as a result, reducing cycle time. High speed milling features a small-in-diameter tool that rotates at high speed and mills material at shallow, light cuts.

The most suitable HSM tool is a solid carbide endmill and ISCAR’s MULTI-MASTER family of assembled endmills, which carry cemented carbide exchangeable heads, also represents a viable option. ISCAR’s line of solid carbide endmills offers various multi-flute tools in diameters of up to 20 mm (.750″), intended for high speed milling materials with hardness up to HRC 70. Decreasing machining allowances due to the production of more accurate workpieces for large parts, for example by using precise casting or molding, opens up new opportunities for high speed milling.

Figure 4

Exchangeable Heads Change The Dynamics

In many cases, manufacturing large parts is small-volume and even individual. In this context, minimizing machine tool downtime has critical importance. Intelligent process planning to considerably reduce setup time can help solve this issue. Each time a worn cutter is replaced, additional measuring and CNC program corrections are required, which increases downtime.

ISCAR’s families of rotating assembled tools with exchangeable heads – MULTI-MASTER mills and SUMOCHAM drills (Fig. 4) – enable substantial decreases in downtime. Face contact between a head and a tool body ensures that the head overhang is within strict tolerance limits, resulting in high dimensional repeatability of the assembly. Replacing a worn head does not require additional setup operations or removal of the tool from a machine.

Figure 5

U-Turn With Turn Milling

Turn milling, which is the method of cutting a rotating workpiece by a face milling cutter, is a good option for machining heavy rotary parts. In turning, the cutting speed is a function of rotating velocity. If the main drive of a machine tool does not allow rotation of large masses with the required velocity, due to limitations of its working characteristics, then the cutting speed is far from the optimal range and turning performance will be low. Turn milling offers an effective solution to the above difficulties. When turning large eccentric parts like crankshafts, off-centre masses of the parts cause unbalanced forces that adversely affect performance. Turn milling features low rotary velocity of a part, which prevents this negative effect (Fig. 5).

The majority of ISCAR’s indexable face-milling cutters are suitable for turn milling. The success of their application depends on cutter positioning with respect to the machined part, choosing optimal geometry of inserts,  and cutting data calculation. ISCAR’s specialists in the field studied turn-milling kinematics and developed an appropriate methodology for defining these parameters.

Reliable Performance

Machining large parts is a time-consuming process, during which the tools cut material for a long period, and this means that tool reliability, stability, and predictable wear are high priority issues. A sudden tool failure may seriously damage the part and even cause its rejection. A cutting tool manufacturer has a limited choice of instruments for improving reliability, including advanced tool design, progressive cutting material,  and technological development. Effective utilization of these instruments is the key to successful large part machining and ISCAR’s recently-introduced range of new tools and carbide grades provides that key.

 

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New Demands, New Solutions

New Demands, New Solutions

New tool holding products mirror modern metalworking demands. Article by Andrei Petrilin, Technical Manager, Rotating Tools, ISCAR.

In general, tool holding (tooling) equipment has not undergone any fundamental changes for a long time. Although there have been some notable advances such as the introduction of quick-change tooling in the 1970’s and the appearance of modular systems using polygon taper coupling and systems based on  HSK adaptation for high rotational speed in the 1990’s, tooling development seems to fit quite firmly into the “if it ain’t broke don’t fix it” category.

Toolholders act as an interface between cutting tool and machine, and they should both ensure proper clamping of the cutting tool and also be suitable for mounting in the fitted spindle or tool changer magazine of a machine tool. The metalworking industry has compulsory standards to strictly specify the matching surfaces for both these purposes. These standards define a wide range of existing tooling systems to meet different manufacturer requirements: simple holders for manual tool changing for conventional machines with hand control, precise high-grade-balanced adaptors for high-speed machining centres. This variety of tool holding arrangements provides the manufacturer with multifold options for effective tool holding, depending on production targets and available machinery. This is mainly why tool holders reached a certain level of excellence that did not require groundbreaking changes.

Today, modern tooling is evolving along with metalworking industry developments in the world of Industry 4.0 and its impact on state-of the-art manufacturing and new technological horizons. Manufacturing digitisation also plays an important part in the development of new tooling features.

Advances in high speed machining (HSM) exemplify the cause and effect of these changes. Implementation of new technologies in this important field has necessitated a new level of tool balancing to ensure tool holder performance and reliability in a significantly expanded range of rotational speeds, with the objective of improving strength, rigidity, accuracy and other technical parameters of the traditionally designed tool holders. High-efficiency milling of difficult-to-cut aerospace materials, like titanium alloys, have increased demands for durable tool holders working in hard conditions.

The effect of these developments can be observed by noting ISCAR’s introduction of a range of tool holding solutions. As one of the largest cutting tool manufacturers in the world, ISCAR is recognised as a strong supporter of constant product innovation.

Today the company offers a rich choice of arbors, holders, adaptors, blocks, thermal and power chucks etc. for effective tool clamping. Following industry demands, performance parameters for these parts have been tightened up significantly. For example, SHRINKIN thermal shrink chucks with HSK 100 shanks now feature G2.5 balance quality and a residual unbalance of less than 1.0 g/mm (.00139 oz/in) at 20,000 rpm, MAXIN 32 power chucks ensure clamping torque up to 1,760 N/m (1,300 lbf/ft), and FINEFIT radial and angular alignment tool holders for high speed reamers maintain radial and axial runout adjustment to 0.001 mm (.00004 in).

Clamping And Cooling

ISCAR recently launched a series of new tooling families that provide an effective pinpointed coolant supply. In many cases, like machining titanium or exotic high temperature superalloys (HTSA), which are common for the aerospace industry, cooling is a critical factor of success.

X-STREAM SHRINKIN is a family of thermal shrink chucks with coolant jet channels along the shank bore. The family utilises a patented design for holding tools with shank, made from cemented carbide, steel or high-speed steel (HSS). The new chucks combine the advantages of high-precision heat shrink clamping with coolant flow, directed to cutting edges. X-STREAM SHRINKIN has already shown excellent performance in milling aerospace parts, particularly titanium blades and blisks (bladed discs), and especially in high speed milling. In machining deep cavities, the efficient cooling provided by the new chucks substantially improves chip evacuation and diminishes chip re-cutting.

Turning

In turning, ISCAR has developed a new concept for high pressure coolant (HPC) supply for VDI DIN 69880 quick-change adaptation systems, intended for turning machine tools. The JETCUT concept is based on bottom-fed HPC channels and provides coolant supply internally through the tool and externally through the flange. The resulting cooling effect significantly improves performance in turning, grooving and parting applications.

A wet coolant can act as an excellent tool in a radically different field: increasing the rotational speed of a tool. ISCAR’s SPINJET family of coolant-driven high speed compact spindles for small diameter tools is a type of “booster” for upgrading existing machines to high speed performers . The SPINJET spindles are recommended for tools up to 7 mm (.275 in) in diameter, however the optimal diameter range is 0.5-4 mm (.020-.157 in). The “booster” demonstrates a highly impressive output: depending on pressure and coolant flow rate, the spindles maintain a rotational speed of up to 55,000 rpm. The versatile SPINJET products have been successfully integrated in tooling solutions for milling, drilling, thread milling, engraving, chamfering, deburring and even fine radial grinding.

Reaming

In reaming, floating chucks are used in high-precision hole making to correct any misalignment between the central axes of a reamer and a hole. Precise alignment is essential for optimal performance and hole accuracy. To this end, ISCAR added a new design of GFIS floating chucks for high speed reamers to the ER COLLET chuck family. The new chuck is unlike any other floating system in the market, due to the integration of a unique technology that ensures the system remains completely rigid until it reaches a steady state of reaming.

Matrix

The Industry 4.0 concept of data-driven smart manufacturing has had a direct impact on the entire chain of production, including the seemingly conservative field of tool holding. In a smart factory, production systems perform under the conditions of real-time mutual information exchange. ISCAR’s modern tool holders incorporate holes for RFID (radio-frequency identification) chips, which can be mounted according to customer request.  ISCAR’s MATRIX intelligent computerized tool storage unit reads the RFID chips and receives all necessary identification data from the tool holder.

These selected examples characterize the development of tool holding products. Despite a “conservative reputation”, the latest tool holding product innovations both reflect and reinforce the trends of metalworking today and beyond.

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Reasons Why Indexable Tools Will Challenge Solid Carbide For Small Diameters

Reasons Why Indexable Tools Will Challenge Solid Carbide For Small Diameters

Rotating one-piece solid carbide tools traditionally dominate the market for diameter ranges of up to 20 mm (.75”) and indexable tool manufacturers have not yet succeeded in penetrating this solid stronghold. Several important factors contribute to the historical perception of solid carbide as a better bet for tooling reliability. 

SOLID carbide tool accuracy compares favorably with that of indexable tools, particularly for small-diameter endmills and for tools with diameters beyond the range. However, the role of reduced accuracy for tools of small diameter (for example, a milling cutter’s radial run-out) increases in significance as a factor affecting tool life.

An indexable tool is made up of a tool body, replaceable inserts, and mechanical parts such as clamping screws or wedges, which secure the inserts in the body. Decreasing the tool diameter necessitates reducing dimensions of the assembly components. Reducing the size of the securing elements leads to weakening their strength and the tool becomes unable to withstand cutting loads under normal machining data. This seriously limits the tool application and further decrements may cause degradation of the entire assembly structure.

The prices of small rotating tools are also often high compared to the assembled concept, which adds to the perceived limitations of indexable tools in the small diameter range.

The Indexable Option

Indexable tools possess several distinct advantages that makes applying these tools within the above range very attractive in the eyes of the customer. In many cases, especially in rough machining, changing a worn cutting edge by simple indexing provides more economic benefits as compared with having to replace a whole life-expired solid tool with a new tool. In addition, there is no need to use up time and resources on regrinding and recoating worn-out one-piece cutters.

Tool manufacturers have made significant progress in developing reliable designs that could be commercially viable against the solid carbide concept. Work in this direction has already shown results, and assembled mills and drills with interchangeable cutting heads are proving to be a realistic alternative to solid carbide tools.

Competitive Performance

 The introduction of tools with replaceable solid carbide cutting heads signifies a change in focus. ISCAR provides two examples of this concept with the ISCAR MULTI-MASTER milling line and the CHAMDRILL line in drilling.

Performance and accuracy characteristics have positioned the new tools to be functionally competitive with solid carbide designs. Versatility of these lines, where a head can be mounted in different bodies and vice versa, where a single body can carry different heads, facilitates various assembly combinations and contributes to reducing the number of items in a tool stock.

Another important design approach which is the “no set-up time”, characterises these lines, as a worn-out head does not require spending time on set up and can be replaced while the tool is still clamped in the machine tool spindle. This cuts cycle time and, consequently, reduces production costs. In contrast, replacing a worn-out solid carbide mill or drill inevitably leads to a new set-up procedure.

In addition, the concept ensures sustainable use of cemented carbide with all the associated advantages. The principle of “indexable” carbide tools has distinct merits and features strongly in tool design within the diameter range that is under discussion. The minimal diameter of MULTI-MASTER milling heads is 5 mm and that of SUMOCHAM drilling heads is 6 mm, while the MULTI-MASTER combined countersink heads for center drilling feature a minimal 1 mm diameter.

The LOGIQ Factor

 ISCAR has recently introduced a new range of small-size indexable rotating tools under its new LOGIQ line campaign. The company proposes several families of cutters with a nominal diameter of up to 20 mm. A brief look at some of these families can provide a clearer understanding as to whether the new tools will be able to breach the solid stronghold wall.

The new families of indexable milling cutters within the diameter range of 8-16 mm attract the most interest. They have several common features: the cutters carry triangular-shape inserts with three cutting edges and the mechanical part that secures the inserts is represented by a screw. These families are intended for milling square shoulder or fast feed (high feed) milling. But it is here that the similarity ends, and the difference begins. While the design of the HELI3MILL and MICRO3FEED families for tool diameter 10-16 mm is committed to the classical principle of insert securing, by clamping screw through the central hole of an insert, the NANMILL and NAN3FEED families for tool diameter 8-10 mm have adopted another concept.

Within such a small diameter range, the central clamping screw, as noted previously, does not provide an acceptable solution. According to the new concept, the screw is located above the insert, and the screw head plays the role of a wedge. This approach provides reliable and rigid clamping, and ensures a durable homogeneous insert structure with no hole. Allowing for the insert indexing to be quick and simple.

It is predicted that these new families will be particularly effective in manufacturing compact parts and in machining small-in-size cavities, pockets and small parts utilised in industrial sectors such as die and mold making, as well as in producing miniature components.

Small Change, Large Impact

 A 1 mm change in size: is this a lot or a little? For indexable tools in the small diameter range, it does make a noticeable difference. ISCAR’s new SUMOCHAM 5 mm diameter drilling head represents an important step ahead in expanding the application fields of indexable drills.

Within the small diameter range, indexable tools can offer precision and performance advantages that position them competitively against the more traditional solid carbide tools.  Indexable tools are beginning to shear their way into metalworking practices and the industry is taking note.

Article contributed by ISCAR.

The Right Grade Creates The Right Tool: Selecting Tool Materials

The Right Grade Creates The Right Tool: Selecting Tool Materials

Cutting tools have different design configurations. Some of them are assembled comprising a body with replaceable cutting elements (indexable inserts, for example), another is wholly produced from solid material. Functionally, a cutting tool may be divided into a cutting part that is involved in cutting, and a mounting part, which is necessary for mounting the tool in a holder or a machine spindle.

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Jet Engine Part Production—An Aerospace Industry Challenge

The requirements for materials used in jet engine parts are necessarily very exacting. They must survive extremes of temperature and force, while being as light as possible and ultra-reliable. Contributed by Iscar

Image Source: Iscar

A turbojet engine can be divided simply into three sections – the compressor, the combustor and the turbine. The compressor pressurises the air flowing through the engine before it enters the combustion chamber, where the air is mixed with fuel, ignited and burnt. The compressor components are predominantly made from titanium alloys, while the combustor and turbine components are typically made of a nickel-based superalloy such as Inconel 718.

Nickel-Based Alloys

The excellent physical properties that characterise nickel-based high temperature alloys make them ideal for use in the manufacture of aerospace components.

Properties such as high yield strength and ultimate tensile strength, high fatigue strength, corrosion and oxidation resistance even at elevated temperatures enable the usage of nickel-based high temperature alloys in many applications and over a very wide temperature spectrum.

The aerospace industry accounts for about 80 percent of the nickel-based high temperature alloys used in manufacturing rotating parts of gas turbines, including  disks and blades, housing components such as turbine casing, engine mounts, and components for rocket motors and pumps.

Nickel-based high temperature alloys contain 35-75 percent Ni and 15-22 percent Cr; they constitute about 30 percent of the total material requirement in the manufacture of an aircraft engine and are also used as structural material for various components in the main engine of space shuttles.

The very same properties that make nickel-based alloys such a great choice for jet engine parts also cause substantial machining difficulties.

The cutting forces and temperature at the cutting zone are extremely high due to the high shear stresses developed and the low thermal conductivity. This, coupled with the reactivity of nickel-based high temperature alloys with the tool material, leads to galling and welding of the chips on the work piece surface and cause excessive tool wear, which can limit cutting speeds and reduce useful tool life.

All these characteristics contribute to low material removal rates and short tool life, resulting in massive machining costs.

Titanium-Based Alloys

Due to their high strength to weight ratio and excellent corrosion resistance, titanium alloy parts are ideally suited for advanced aerospace systems. Titanium-based alloys which contain 86-99.5 percent Ti and 5-8 percent Al, are immune to almost every medium to which they would be exposed in an aerospace environment.

Image Source: Iscar

Very large quantities of titanium can be found in jet engines, where titanium alloy parts make up to 25-30 percent of the weight, primarily in the compressor. The high efficiency of these engines is obtained by using titanium alloys in components such as fan blades, compressor blades, rotors, discs, hubs, and other non-rotor parts—for instance inlet guide vanes.

Titanium’s superior properties and light weight allow aeronautical engineers to design planes that can fly higher and faster, with high resistance to extreme environmental conditions. However, titanium has historically been perceived as a material which is difficult to machine due to its physical, chemical and mechanical properties.

The material’s relatively high temperature resistance and low thermal conductivity do not allow generated heat to dissipate from the cutting tool, which causes excessive tool deformation and wear. Titanium alloys retain their strength at high temperatures, resulting in relatively high plastic deformation of the cutting tool resulting in depth of cut notches. During machining, the high chemical reactivity of titanium alloys causes the chips to weld to the cutting tool, leading to built-up cutting edges and chip breakage problems.

Over the past few years, Iscar has invested many resources in research and development to resolve these obstacles and optimise the machining of nickel-based and titanium high temperature alloys, with solutions that include the creation of customised grades and implementation of high pressure coolant technologies to develop cutting tools that will handle the heat issues.

Grades

For high material removal rates, Iscar developed ceramic grades to facilitate machining nickel-based alloys at cutting speeds of 200–400m/min:

IW7—Whisker-reinforced ceramic grade, provides high hardness with excellent toughness used for roughing and semi-finishing continues operations at 8-10 times faster cutting speeds when compared with carbide grades.

IS25—Reinforced SiAlON composite grade, Excellent for machining Ni based high temperature alloys at continuous and light interrupted applications.

IS35—Reinforced SiAlON composite grade, Excellent for machining Ni based high temperature alloys at light & heavy interrupted applications.

A series of carbide grades was developed specifically to create tools for machining nickel-based and titanium alloys:

IC806—A hard submicron substrate combined with a thin TiAlN PVD coating. The unique coating procedure which involves a special post coating treatment creates a thinner and smoother coating layer providing the insert with the best characteristics suitable for machining nickel-based and titanium alloys.

IC804— Same TiAlN PVD coating on a harder submicron substrate designed especially for machining Ni based alloys used in newly designed jet engine parts that feature very high hardness (40-47 HRC).

IC20—An uncoated carbide grade which is highly recommended for machining aluminum and titanium. IC20 provides very high performance and is mostly used for continuous cut applications.

High Pressure Coolant Tools

Image Source: Iscar

Although high pressure coolant features have been in existence for a long time in the metal removal world. Today high pressure coolant tools play an increasingly significant role in the machining process, facilitating enhanced productivity and chip control especially for hard to machine materials such as titanium and nickel-based alloys. Incorporating high pressure is the key to directing coolant to exactly where it is needed in order to flush the chips away from the cut.

Iscar was one of the first cutting tool producers to respond to market needs by developing and manufacturing tools for the optimal use of high pressure coolant in lowering high temperatures and regulating chip flow, including Jetcut custom high-pressure coolant tools.

While the aerospace parts OEM/PMA sector is under constant pressure to keep costs down, the quality and life expectancy of the parts produced cannot be compromised—and this represents an enormous challenge for all involved.  Iscar’s enhanced cutting tools allow jet engine manufacturers to utilise the ideal materials for the production of high quality parts, with minimum wastage and maximum efficiency.

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