Tungsten Carbide Lathe Tool Inserts

tungsten carbide lathe tool inserts are widely used in metal cutting applications like turning, milling and drilling to efficiently machine parts to precision dimensions and fine surface finish thanks to their extreme hardness, wear resistance, and thermal properties. This guide offers a detailed look at various grades and geometries of tungsten carbide inserts specified for different materials and lathe turning operations.

Overview of tungsten carbide lathe tool inserts for Turning

Engineered with a hard carbide composition dispersed in tough cobalt metal matrix, tungsten carbide inserts are a popular choice of cutting tool material for single point turning and grooving in automatic lathes, screw machines, CNC lathes and machining centers owing to advantages like:

  • Extreme hardness and wear resistance for high metal removal rates
  • Strength to withstand cutting forces and shocks at elevated temperatures
  • Thermal shock resistance for stable precision machining
  • Chemically inert to work materials like steel, stainless steel, cast iron, heat resistant superalloys, titanium and nickel-based alloys
  • Reusable by rotating/indexing to utilize multiple cutting edges
  • Coated grades offer higher lubricity, heat resistance, wear protection

Proper insert shape, size, grade selection coupled with optimized operation parameters maximizes productivity in turning high performance alloys, tough aerospace materials and common engineering metals.

Types of tungsten carbide lathe tool inserts

Tungsten carbide inserts come in various standard sizes, geometries with special profiles, coatings and identifiers denoting grade to suit different workpiece attributes and machining requirements:

Tungsten Carbide Grades for Turning Inserts

Carbide grade influences strength, fracture toughness, heat and wear resistance. Common classifications:

GradeDetailsTypical Uses
C1-C4Straight tungsten carbides with 6-10% cobalt binderGeneral machining of low/medium alloy steels
P10-P50Fine grained carbides for improved hardness and heat resistanceHigh speed steel turning applications
M10-M40Tougher grades containing titanium carbide (TiC), tantalum carbide (TaC) additionsTough materials like stainless steel, heat resistant superalloys
K10-K40Containings specialized carbides like niobium carbide (NbC) for extreme wear resistanceDifficult-to-machine nickel alloys, hardened steels

Higher grade number indicates better hot hardness, heat and wear resistance.

tungsten carbide lathe tool inserts

Tungsten Carbide Insert Coatings

CoatingCompositionKey Features
TiNTitanium nitrideHigh hardness, lubricious golden finish
TiCNTitanium carbonitrideResistance to heat and crater wear
TiAlNTitanium aluminum nitrideHigh hot hardness and oxidation resistance
AlCrNAluminum chromium nitrideExcellent wear resistance and lubricity

Multilayer, nanostructured, superlattice coatings can combine beneficial properties for demanding applications. Uncoated inserts are still widely used for short runs in easier materials.

Tungsten Carbide Insert Shapes/Styles for Turning

Common options include:

ShapeFeaturesUses
SquareFour cutting edges, mechanical clampingLow cost general purpose roughing
RoundRound insert shape, center screw clampingFinishing in grooves, rounds
TrigonTriangle shape with 3 cutting edgesMedium roughing applications
Diamond35° rhombic shape for strengthInterrupted cuts, high feed mill-turn
DovetailSpecial clamping groove geometryHigh precision machining

Various custom and proprietary shapes also offered for specific turning operations or tool holder systems.

In addition to shape, important insert dimensions like inscribed circle size, thickness, nose radius, lead angle and hand of cut determine suitability for facing, profiling, parting/grooving, boring, threading and other applications.

Properties of tungsten carbide lathe tool inserts

Key performance attributes stem from composition and microstructure:

Tungsten Carbide Insert Properties

PropertyRole
HardnessResist deformation, enables faster metal removal
Fracture toughnessAvoid brittle failure under machining loads
Transverse rupture strengthWithstand cutting forces without breaking
Resistance to plastic deformationRetain shape accuracy and surface finish
Thermal conductivityManage heat at tool-workpiece interface
Coefficient of thermal expansionCompatibility with substrate to prevent inserts popping out

Grain size, binder content and composition are optimized in various carbide grades to maximize a combination of hardness, strength and toughness needed for specific machining scenarios.

Manufacturing Process for Tungsten Carbide Inserts

Key steps in fabrication of tungsten carbide turning inserts:

Tungsten Carbide Insert Manufacturing Sequence

StepDetails
Powder processingCarbides like WC, TiC, TaC blended with Co binder
CompactionPressing into green compact shape
Sintering1300-1500°C furnace treatment to develop dense microstructure
GrindingProfile grinding to accurate geometry
Edge preparationSpecial edge treatments for chip control, less friction
CoatingOptional PVD/CVD coating deposition
PackagingProtective packaging for shipment

Strict process controls during mixing, pressing, sintering, edge preparation and coating result in precision inserts delivering consistent tool life and machining performance.

Applications of tungsten carbide lathe tool inserts

Tungsten carbide is extensively used for single point external turning operations on manual lathes, CNC lathes, screw machines and machining centers.

Tungsten Carbide Insert Turning Applications

MaterialComponentsBenefits
Carbon, alloy steelsShafts, cylinders, bushingsHigh metal removal rates
Stainless steelsValve bodies, pump parts, fastenersCorrosion resistance for medical, food, marine parts
Heat resistant superalloysTurbine disks, combustor liners, transitionsWithstand extreme environments
Titanium, nickel alloysAircraft hydraulic/fuel tubes, IGT partsStrength-to-weight ratio
Cast ironAutomotive cylinders, gearbox casingsDimensional accuracy
Hardened steelsCutting tools, molds, diesPrecision components

Indexable insert tooling systems allow quick changeover between operations, minimizing downtime for producing high precision turned parts across industries.

Tungsten Carbide Insert Standards and Specifications

Standardization of insert dimensions, identification nomenclature, packaging, testing methods facilitates usage across global supply chain:

Tungsten Carbide Insert Standards

StandardOrganizationRole
ISO 1832International Organization for StandardizationInsert designation code with shape, size, tolerance, direction info
ANSI B212.4-1986American National Standards InstituteCarbide insert standards guide
JIS B4122Japanese Industrial Standards CommitteeCarbide cutting tool specifications
GB/T 20866Standardization Administration of ChinaCarbide insert specification

Imposed by tooling manufacturers, suppliers also implement strict grades and quality control benchmarks:

Typical Carbide Insert Specifications

ParameterRange / Benchmark
Density>14.5 g/cc
Hardness88-93 HRA (Rockwell A scale)
Transverse rupture strength>350 kgf/mm<sup>2</sup>
Coating thickness3-5 μm
Coating adhesionHF1-2 per ISO 26443

These thresholds validate superior performance linked to precision dimensions, coating quality, microstructure uniformity and freedom from defects.

Global Suppliers of Tungsten Carbide Inserts

Prominent makers and distributors of tungsten carbide turning inserts include:

Tungsten Carbide Insert Brands

CompanyGradesCoatings
Sandvik CoromantC, P, M, KTiN, TiCN, TiAlN, AlCrN
KennametalC, M, K, beyondTiAlN, AlTiN, TiSiN
WIDIA (Iscar)C, P, MTiN, AlTiN, TiSiN
Walter ToolsStandard + custom gradesTiCN, AlCrN, TiAlCrN
SumitomoCustomized micrograin gradesProprietary AC2000, AC3000
Kyocera UnimercoUltra-fine grained gradesMultilayer coatings
TungaloyCustomized ultra-hard gradesTiOCN, AlCrON
GuhringUltra-wear resistant spec. carbide gradesTiAlN, TiCN, thick TiN+AlCrN

Most manufacturers offer inserts in all common sizes and geometries tailored for various work materials, operations and tool holder systems.

Grade, coating and tolerances differentiate premium insert lines claiming longest tool life and most consistent machining performance albeit at higher price levels compared to value brands.

Comparative Analysis: Carbide Insert Types

Key differences between tungsten carbide insert options:

ParameterCoated carbide insertCeramic insertcBN insertPCD insert
CompositionWC-Co carbide-metal matrixAlumina or silicon nitride ceramicsCubic boron nitride-ceramic mixDiamond particles in metallic/ceramic binder
HardnessVery hard 88-93.1 HRAExtremely hard up to 95 HRAClose to diamond; over 45 GPaHardest; up to 80 GPa
Fracture toughnessMuch higherMore brittleBrittleRelatively brittle
Thermal conductivityModerateLowHighHigh
Friction coefficient0.15-0.35 typical0.20-0.800.05-0.500.05-0.25
Temperature limit600-1000°CAround 1000°C1400°C700°C

While more expensive inserts like PCD provide ultimate tool life and consistency in some alloys, limited cutting parameters make coated carbide the workhorse for production turning jobs across easier and harder metals.

tungsten carbide lathe tool inserts

Advantages and Disadvantages of Tungsten Carbide Inserts

Pros and Cons of Carbide Inserts for Turning

AdvantagesDisadvantages
Extremely hard and wear resistantBrittle with lower fracture toughness than HSS tools
Maintains hardness value at higher temperaturesShock sensitive requiring rigid setups, smooth operation
Chemically inert to most engineering materialsExpensive consumable, need for optimization
Allows faster cutting parameters and lower cycle timesProper selection and usage technique essential
Indexable inserts provide multiple cutting edgesSpecial tooling, holders required
Wide range of geometries, sizes and tolerance availabilityLimitations on depth of cut versus solid carbide tools
Applicable for most materials from plastics to hardened metals heat resistant superalloysRegrinding or resharpening not feasible

While demanding on setup rigidity, machine capability and level of operator skill, carbide inserts rightly dominate as material of choice for most production turning tasks favoring their supreme tool life and productivity benefits at moderate step-up in initial insert cost over HSS.

Frequently Asked Questions

Q1: Why are some tungsten carbide inserts black in appearance?

Answer: Dark appearance comes from TiAlN or similar wear-resistant PVD coating applied in thickness of 2-5 microns to provide lubricious protective layer that combats wear and welding during machining at higher temperatures.

Q2: When should a tungsten carbide insert be replaced?

Answer: Criteria for insert index or replacement includes dimensional tolerance drift exceeding specified limit due to flank wear, catastrophic chipping or fracture that leaves used cutting edges unserviceable, crater wear degrading work finish, or noticeable build up of material on rake face inhibiting chip flow and evacuation.

Q3: How to select the best tungsten carbide insert shape for production turning?

Answer: Square inserts offer four usable cutting edges and low per edge cost for roughing cuts while triangle or diamond inserts provide added strength for interrupted cuts. Round inserts excel in finishing grooves and profiles. Insert style can dictate suitable cutting tool holders.

Q4: What is the role of lead angle on tungsten carbide turning inserts?

Answer: Lead angle or plane rake tilts insert’s major cutting edge relative to base, varying contact area. Positive lead angles around +25° suit finishing as it lowers forces while negative lead angles approaching -25° benefit roughing by increasing strength.

Q5: Should tungsten carbide inserts be stored in any special manner?

Answer: Carbide inserts need proper enclosed storage in abrasion-resistant, labeled compartments to prevent contact or edge damage during handling. Controlled humidity environment prevents premature coating failure or spot corrosion.

know more Tungsten carbide

Share This Post:

Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents

Most Popular

Get In Touch

Get in touch with us

Please enable JavaScript in your browser to complete this form.
On Key

Related Posts

negative rake carbide inserts

negative rake carbide inserts

Imagine this: you’re a sculptor, meticulously shaping a stubborn block of granite. Your chisel, the instrument of your vision, keeps dulling with each forceful strike. Now, picture a revolutionary tool

negative rake carbide inserts

Square Carbide Inserts

Imagine this: you’re in the throes of a metalworking project, meticulously shaping a piece of steel to your exact specifications. But then, disaster strikes! Your cutting tool dulls, leaving behind

negative rake carbide inserts

shars carbide inserts

Carbide inserts are the workhorses of the metalworking world. These small, incredibly tough blades are used in lathe tools, milling machines, and other cutting applications to shape and refine metal.

negative rake carbide inserts

Face Mill Carbide Inserts

Imagine you’re a sculptor, meticulously shaping a raw block of stone into a masterpiece. But instead of stone, your canvas is metal, and your chisel is a face mill. Now,

Contact Truer Now

Please enable JavaScript in your browser to complete this form.