Various metals and steel alloys are shaped using inserts. To obtain the desired form for acceptable turning materials, it will be necessary to use inserts of the proper shape and quality.

Why Do Carbide Inserts Need?

Carbide inserts are utilized to precisely mill metals, such as steels, carbon, cast iron, high-temperature alloys, and non-ferrous metals. These are replaceable and are available in several designs, qualities, and sizes.

There are several significant factors to consider while selecting the proper carbide inserts. Whether for Turning, Milling, or Drilling, the cutting operation is one. Carbide is more costly per unit and more brittle than other standard tool materials, making it more subject to chipping & breaking. The carbide cutting tip is frequently a tiny insert for a more extensive pointed tool whose shank is typically constructed of carbon tool steel to overcome these issues. It provides the advantages of utilizing carbide at the cutting contact without the high expense and brittleness of constructing the entire tool from carbide. Many lathe tools & endmills employ carbide inserts, as do most contemporary face mills.

Utilizing carbide inserts at high speeds enables quicker machining, which eventually results in superior finishing. Proper selection is crucial because improper carbide inserts can damage the insets, machine, or cutting product.

Why are carbide inserts so superior?

Those are some of the causes why carbide inserts are superior to other types of cutting tools:

• Carbide inserts are particularly efficient & cost-effective compared to other cutting tools of a similar nature.
• Some carbide inserts, such as tungsten, are highly durable and extend the work life.
• Carbide inserts are available in various forms and grades for usage in various applications.
• Carbide inserts give a superior surface polish compared to other types of tools.

Components Of Inserts

Inserts are often formed of carbide, segments and sub carbide, ceramic, CBN, cermet, diamond PCD, chrome, silicon nitride, and high-speed steel, among other materials. The coating on the insert increases this cutting tool’s wear resistance and durability. These coverings include titanium nitride, chromium nitride, aluminum titanium nitride,  zirconium nitride, titanium carbonitride, and diamond DLC.

Inserts of carbide and their geometry

There are three fundamental geometries for carbide inserts optimized for various processes, including roughing, finishing, or medium. The figures below illustrate the working area of each geometrical form based on the geometrical chip breaking with a depth of cut.

Selecting Carbide Inserts 3

Roughing is a combination of a substantial depth of cut and feed rate. This operation demands the highest level of edge security.

Selecting Carbide Inserts 2

Finishing involves shallow cut depths and low feed rates. Low cutting forces are required for this procedure.

Selecting Carbide Inserts

Medium

This procedure comprises a variety of deep-cutting and feed-rate configurations.

Entering Tilt for Inserts

The entering angle, KAPR, is formed between the feed direction and the cutting edge. Choosing the right entering/lead angle is crucial for a turning operation to be effective. The entrance/lead angle impacts:

• Chip morphology
• The orientation of slicing forces
• Length of cutting edge in cut

Forms of Carbide Inserts

Depending on their shape and composition, several types of carbide inserts serve a variety of applications. These inserts are changeable attachments for cutting instruments whose natural cutting edge is often the cutting edge itself. These carbide inserts contain the following:

• Hobbing
• Milling
• Mining
• Tapping
• Sawing
• Drilling
• Grooving
• Terminated and parting
• Shearing \sCutting
• Threading
• Turning
• Brake rotor rotation
• Inserts made of carbide have various geometrical forms. For example:
• Circular / Round Inserts

Alternatively, round circular carbide inserts are utilized in button milling and radius groove turning applications.

Insertions of Triangles and Triangles

Triangle or Trigon carbide inserts feature three equal sides and three points with 60-degree angles. They are triangular inserts with a modified shape, such as bent sides or medium-sized angles with chamfers at the points.

Four-Sided Carbide Inserts

Carbide inserts with four sides are available in diamond, square, rhombic, and rectangular geometries. Four-sided diamond-shaped carbide inserts with two sharp corners for material removal.

Square

Square carbide inserts have 4 equal edges. In contrast, rectangular carbide inserts consist of four sides. Two sides are longer than the remaining two. These sorts of carbide inserts are used for grooving, with the cutting edges located on the short sides of the inserts.

Rhombic / Parallelogram

The sides of a rhomboid or parallelogram-shaped carbide inserts are likewise angled for cutting point clearance.

Other shaped carbide inserts include the pentagon, which has five equal sides and angles, and the octagon, with eight sides.

In addition to their forms, carbide inserts are distinguished by their tip angles. Here are a variety of carbide inserts with varying tip angles:

Ball Nose Mill: A ball end mill carbide insert features a ‘hemispherical’ ball nose with a radius half the cutter’s diameter. This carbide insert assists in the machining of female semicircles, grooves, and radii.

A radius tip mill carbide insert is a straight insert with radiused tips. This carbide insert is utilized in milling cutters.

Chamfer Tip Mill: A chamfer tip mill has an angled segment on its tip to create an angled cut or chamfered edge on the workpiece.

Dog bone Carbide Insert:

It is a two-edged insert with a tiny mounting center and a wider cutting edge on both sides. This carbide insert is utilized for grooving. The angles of its tips range between 35, 50, 55, 60, 75, 80, 85, 90, 108, 120, and 135 degrees.

What Are the Primary Applications For Carbide Inserts?

Since the late 1920s, carbide implants have been utilized. These cutting instruments are prevalent in the realm of metal cutting. Here are some applications of carbide inserts in the metal cutting business. Carbides are helpful for many company owners, construction workers, and workers in several other sectors throughout the world.

Producing Surgical Instruments

Insert carbides are one of the instruments that physicians and surgeons rely on for all types of medical operations that require precision and durability.

Carbides are utilized most often in the medical field. However, the tool’s base is composed of titanium or stainless steel, while the tool’s tip is constructed of tungsten carbide.

Jewelry Crafting

In the jewelry-making industry, carbide inserts are commonly employed. They are employed in both the shape and composition of jewelry. Tungsten material is second only to diamond in terms of hardness, and it is a good material for wedding rings and other jewelry.

In addition, jewelers rely on efficient tools to work on pricey items, like carbide and tungsten inlays.

Atomic Science

Tungsten carbide inserts are also excellent neutron reflectors in the nuclear research business. This substance was also utilized during early studies of nuclear chain reactions, particularly for protecting weapons.

Hard Turning & Milling

Turning ceramics is a virtually perfect procedure. In general, it is a system for continuous machining that permits a single carbide insert to remain in the cut for a more extended period. It is a fantastic instrument for generating the high temperatures required to optimize the performance of ceramic inserts.

On the other hand, milling is comparable to interrupted machining in turning. Each carbide insert on the tool body enters and exits the cut with each cutter turn. Hard milling requires much greater spindle speeds to obtain the same surface speed for efficient operation compared to turning.

To match a turning mechanism’s surface speed on a three-inch diameter workpiece, a three-inch milling cutter with four teeth must operate four times the turning speed. With ceramics, each insert creates a minimum amount of heat. Therefore, each insert must move quickly to create the same amount of heat as a single-point rotating tool during milling operations.

Advice for Confronting the Difficulties of Cast Iron Machining

Cast irons are currently more sophisticated than they were twenty years ago. They are more inexpensive, lighter, and more durable. Cast iron is an excellent alternative to steel if under persistent cost-cutting pressure. However, several variables and obstacles to consider when determining the appropriate tools for your cast iron machining processes.

Initially, it is essential to comprehend the many cast-iron forms and recognize that each has extraordinary strength, cost, and machinability. In addition, there are several grades for each of these categories with vastly distinct mechanical characteristics.

Here are a few varieties of modern cast iron from which to choose:

• Grey cast iron, one of the most popular and cheapest forms, contains carbides in the form of lamellar graphite particles, which gives it excellent vibration dampening qualities and makes it a suitable material for engine components. In addition, its machinability is superior to that of other varieties.
• Compared to grey cast iron, vermicular cast iron, also known as compressed graphite iron, has more strength and less weight. Because vermicular cast iron is excellent for mechanical and thermal stress components, automakers increasingly employ it to produce cylinder heads and brake components.
• Cast silicon-alloyed ferritic ductile iron is suited for manufacturing wheel hubs and axles. Due to its outstanding machinability and superior mechanical qualities, the material is gaining popularity in the automobile sector.
• Nodular ductile cast iron, which consists of spheroidal nodular graphite particles in ferrite and pearlite matrix, possesses high ductility, good fatigue strength, superior wear resistance, and a high modulus of elasticity; consequently, it is the material of choice for transmission housings and wheel suspension components in the automotive and heavy equipment industries.
• Austempered ductile iron has high strength, high fatigue strength, strong wear resistance, and high elongation to fracture values, making it a very competitive material compared to many cast and forged steels. Due to its high strength and elasticity, austempered ductile iron has the lowest level of machinability among the other forms of cast iron described.
• Companies that manufacture cutting tools, such as Seco, are continually creating new turning and milling solutions to tackle the variations and difficulties associated with dealing with cast iron materials. However, this can be a challenge in and of itself, as each material, manufacturer, and application around the globe is unique. Nonetheless, here are some essential considerations you should constantly bear in mind:
• Variations in the qualities of your workpiece can have a detrimental effect on your overall production, either directly or indirectly. When workpiece qualities are unknown, tooling systems and cutting methods can be used to compensate for any material quality deficiencies. The challenge is determining which tools and tactics are optimal for your application.
• Regarding turning cast iron, everything relies on the application at hand. You must determine the number of activities required to achieve your objectives. If the qualities of your workpiece are uncertain, you may decide to incorporate an additional finishing cut, which can affect lead product times. However, you may decrease the number of procedures by using the appropriate equipment for the component’s circumstances and specifications.
• There is more intricacy involved in milling cast iron than in turning it. It is necessary to consider the insert grade, but it is more crucial to consider the entire cutting solution. In addition, to insert geometries and grades, you must also consider cutter body types and the number of cutting edges about your component. In addition, neither heat nor coolant is suitable for milling cast iron.
• There is no one-size-fits-all solution regarding the optimal cutter type for milling cast iron. In general, however, the sort of milling cutter that appears to be gaining the most traction is a negative cutter with inserts with positive rake angles and a grade that can withstand both wet and dry circumstances.
• While a single type of cutter may be able to cut all sorts of cast irons satisfactorily, this does not imply that it can manufacture every form of workpiece shape. You must consider the surface you will be slicing and ask: Is it rectangular or long? Are the thicknesses of the walls small or thick, fragile, or stable? Moreover, how secure is the clamping of workpieces?
• It would help if you considered your machine tool. When milling cast iron materials, there is more significant dynamic stress. Therefore your machine tool must be highly durable and provide high power and high stability – all of which strain the machine. In these situations, however, a negative cutter with a positive rake angle can assist minimize the power needs of the machine tool and the stress on machine spindles.

Final Thoughts

Carbide inserts mill steels, carbon, cast iron, high-temperature alloys, and other non-ferrous metals. Carbide is pricier and more brittler than other tool materials. Finishing requires shallow cuts and low feed rates. Depending on shape and composition, carbide inserts have different geometric shapes. Carbide implants have been used since the 1920s. Carbides aid business owners, construction workers, and others. Tungsten is second only to diamond in hardness and makes excellent wedding bands. Cast iron is a cost-effective alternative to steel. Grey cast iron is affordable and popular. Nodular ductile cast iron is ductile, fatigue-resistant, wear-resistant, and elastic. Workpiece quality can directly or indirectly affect output. Every material, manufacturer, and application is unique.