Diamond-Coated Cutting Blade with Uniform CVD Crystallinity

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In diamond-coated tools, uneven thickness and crystallinity of the diamond layer lead to increased wear and peeling, reducing tool life.

Innovation Solution

A diamond-coated tool with a diamond layer of uniform thickness and crystallinity is achieved by controlling the temperature distribution during the hot filament CVD process, ensuring the thickness ratio and crystallinity measurements meet specific criteria across the blade, thereby extending tool life.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a diamond layer is formed on a base material by conventional CVD process, then the tool has wear resistance, but the diamond layer thickness and crystallinity become uneven, leading to increased wear and peeling

Engineering Contradiction:
Improvetool lifeVSAvoiddiamond layer thickness uniformity
Core Design Contradiction:
ReliabilityVSManufacturing precision

Solution Approach 1:

The patent applies parameter changes by precisely controlling the temperature distribution during the CVD process. By maintaining the temperature distribution within 5% uniformity, the diamond layer thickness and crystallinity become uniform across the blade surface, eliminating the unevenness that causes premature wear and peeling. This parameter control directly resolves the contradiction between achieving wear resistance and maintaining manufacturing precision.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent implements feedback control through temperature monitoring and adjustment during the CVD process. By measuring the actual temperature distribution and adjusting heating parameters to maintain uniformity within 5%, the system ensures consistent diamond layer quality. This feedback mechanism prevents thickness variation and crystallinity defects, thereby extending tool life while maintaining manufacturing precision.

Inventive Principle:
Principle #23Feedback

2Ease of manufacture

If the diamond layer thickness varies across the blade, then the coating process is simpler, but the wear and peeling occur more frequently, reducing tool life

Engineering Contradiction:
Improvecoating process simplicityVSAvoidtool life
Core Design Contradiction:
Ease of manufactureVSDuration of action of moving object

Solution Approach 1:

The patent maintains the simplicity of the CVD coating process while introducing precise temperature control as a critical parameter. By focusing on controlling the temperature distribution uniformity (within 5%) rather than complicating the overall process, the patent achieves uniform diamond layer thickness and crystallinity. This approach extends tool life without significantly increasing manufacturing complexity.

Inventive Principle:
Principle #35Parameter changes

3Productivity

If the temperature distribution during CVD is not controlled, then the manufacturing process is faster, but the diamond layer crystallinity becomes uneven, increasing wear and peeling

Engineering Contradiction:
Improvemanufacturing speedVSAvoiddiamond layer crystallinity uniformity
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent introduces temperature distribution control as a key parameter during the CVD process. By maintaining temperature uniformity within 5%, the diamond layer achieves consistent crystallinity across the blade surface. This parameter control prevents the formation of weak spots that would lead to premature wear and peeling, thereby improving reliability without significantly reducing manufacturing speed.

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

The uniform diamond layer results in reduced wear and peeling, significantly extending the tool's lifespan and maintaining performance.

Implementation Method 1

forming a diamond layer on the base material by a hot filament CVD process

Methodology Applied
Scientific EffectChemical Vapour Deposition: Chemical Vapour Deposition

Data Source

PatentEP4056728A1Diamond-coated tool and method for manufacturing same
Publication Date: 2022.09.14 SUMITOMO ELECTRIC HARDMETAL CORP
  • EP4056728A1 patent drawingFigure 1
  • EP4056728A1 patent drawingFigure 2
  • EP4056728A1 patent drawingFigure 3

AI summary

In a diamond-coated tool provided with a blade which includes a base material and a diamond layer formed on the base material, when a length of the blade along an extending direction thereof is denoted by L, and a thickness of the diamond layer of the blade is measured at a total number of 11 points which are arranged from one end of the blade along the extending direction thereof and separated from each other at an interval of L/10, the thickness is the same at all of the 11 points, or a ratio dmin/dmax between a minimum value dmin of the thickness and a maximum value dmax of the thickness is 0.7 or more and less than 1.