Thin Ceramic Wafer Bonding for Indexable Cutter Inserts

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

There is a need for an efficient method to produce indexable cutter inserts for machine tools that enhance productivity and reduce material wastage while improving the utilization of ceramic material sintering equipment, while also providing enhanced fracture resistance and robustness against cracking.

Innovation Solution

The method involves creating a ceramic wafer with a mean thickness of up to 2 mm, unsupported by a substrate, which is bonded to an insert base using a braze alloy material, allowing for the efficient use of PCBN material and reducing residual stress, thereby enhancing manufacturing efficiency and fracture resistance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a thick ceramic wafer is used to ensure structural strength, then fracture resistance improves, but material wastage increases and manufacturing efficiency decreases

Engineering Contradiction:
Improvefracture resistanceVSAvoidmaterial wastage
Core Design Contradiction:
StrengthVSLoss of substance

Solution Approach 1:

The patent changes the thickness parameter of the ceramic wafer from conventional thick designs to a thin design (at most 2mm mean thickness). This parameter change is made possible by the unsupported wafer configuration, which allows thin sections to maintain sufficient strength while dramatically reducing material consumption and improving manufacturing efficiency.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent extracts the support substrate from the ceramic wafer structure, creating an unsupported free-standing wafer. This extraction eliminates the need for thick sections required for structural support, allowing the wafer to be made thin (at most 2mm) while maintaining integrity through the bonding process, thereby reducing material wastage and improving manufacturing efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

2Reliability

If ceramic material is sintered into a thick compact to ensure durability, then reliability improves, but productivity of sintering equipment decreases

Engineering Contradiction:
ImprovedurabilityVSAvoidsintering equipment utilization
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent changes the thickness parameter of the ceramic wafer to at most 2mm, which significantly reduces the sintering time and energy required. This parameter change increases the productivity of sintering equipment while maintaining durability through the optimized thin-wafer design and bonding process.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

By removing the support substrate and creating an unsupported thin wafer configuration, the patent enables faster sintering cycles. The thin wafer (at most 2mm) requires less sintering time and energy, thereby increasing equipment utilization and productivity while maintaining reliability through the bonding process.

Inventive Principle:
Principle #2Taking out (Extraction)

3Strength

If high-temperature integration is used to bond ceramic to substrate, then bonding strength improves, but residual stress increases causing cracking

Engineering Contradiction:
Improvebonding strengthVSAvoidresidual stress and cracking
Core Design Contradiction:
StrengthVSObject-affected harmful factors

Solution Approach 1:

The patent changes the bonding parameters by using a braze alloy material with a lower melting point than traditional high-temperature integration methods. This allows bonding to occur at reduced temperatures, minimizing thermal gradients and residual stress while maintaining adequate bonding strength for the application.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent introduces a braze alloy material as an intermediary bonding layer between the ceramic wafer and the support structure. This intermediary material enables bonding at lower temperatures compared to direct high-temperature integration, reducing residual stress and cracking while providing sufficient bonding strength through the eutectic reaction of the braze alloy.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Productivity

If thin ceramic wafers are used to reduce material cost, then manufacturing efficiency improves, but fracture resistance decreases

Engineering Contradiction:
Improvemanufacturing efficiencyVSAvoidfracture resistance
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The patent optimizes the thickness parameter of the ceramic wafer to at most 2mm, which is thin enough to improve manufacturing efficiency and reduce material cost but thick enough to maintain adequate fracture resistance. This optimized parameter, combined with the bonding process, achieves the balance between manufacturing efficiency and structural integrity.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach results in improved manufacturing efficiency, reduced material wastage, and enhanced robustness against cracking during handling and use, as the ceramic wafer is securely bonded to the insert base without the need for high-temperature integration, leading to a more durable and cost-effective indexable cutter insert.

Implementation Method 1

bonding the ceramic wafer to the insert base using a braze alloy material

Methodology Applied
Scientific EffectBrazing: Brazing

Implementation Method 2

cutting the precursor body into two to ten substructures, each having a volume of 50% down to 10% respectively, of the volume of the precursor body

Methodology Applied
Scientific EffectElectrical discharge machining: Electrical Discharge Machining

Data Source

PatentEP2593255B1Method for making a construction for an indexable cutting insert
Publication Date: 2016.10.12 ELEMENT SIX LTD
  • EP2593255B1 patent drawingFigure 1A~1B
  • EP2593255B1 patent drawingFigure 2A~2B
  • EP2593255B1 patent drawingFigure 3~4

AI summary

A method of making a construction for an indexable cutter insert, the method including providing a wafer (20) comprising ceramic material, the wafer (20) being substantially unsupported by a cemented carbide substrate and having a mean thickness of at most 2 mm; providing an insert base (30) having proximate and distal major ends (33, 34) connected by peripheral sides (36), the proximate end (33) of the insert base (30) being configured to have at least two corners (35) defined by junctions of the peripheral sides (36); the wafer (20) being configured to have at least two corners (25) corresponding to the two corners (35) of the proximate end (33) of the insert base (30); the method including bonding the wafer (20) to the proximate end (33) by means of a bond material, the corners (25) of the wafer (20) being disposed adjacent the corresponding corners (35) of the proximate end (33) to provide the construction.