cBN Sintered Body Composition for Ceramic Coating Adhesion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional cubic boron nitride (cBN) sintered bodies exhibit inadequate adhesiveness to ceramic coating films, leading to peeling and defects during cutting and grinding of high hardness materials, particularly at discontinuous portions and high hardness steel surfaces.
Innovation Solution
A cBN sintered body with a composition of 60.0 to 90.0% cBN and a binder phase containing W2NixCo(1-x)B2, TiB2, and other compounds, sintered under specific conditions to enhance wear resistance, defect resistance, and adhesiveness to ceramic coatings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If a ceramic coating film is applied to improve heat resistance, then heat resistance is improved, but adhesiveness deteriorates causing peeling during cutting
Solution Approach 1:
The invention changes the chemical composition parameters of the binder phase by incorporating specific compounds (W2NixCo(1-x)B2 with controlled x values, TiB2, Al compounds) in precise proportions. This compositional parameter optimization creates a binder phase that provides both thermal stability for heat resistance and chemical bonding capability for adhesiveness to ceramic coating films.
Solution Approach 2:
The invention creates a composite binder phase system combining multiple elements (W, Ni, Co, Ti, Al, B) in specific compounds. This composite material approach allows the binder phase to simultaneously provide heat resistance through refractory compounds and adhesiveness through controlled chemical interactions with ceramic coating films, resolving the contradiction between these two properties.
2Stability of the object's composition
If conventional binder phases are used to maintain structural integrity, then structural stability is maintained, but adhesiveness to ceramic coating films deteriorates
Solution Approach 1:
The invention modifies the binder phase composition parameters by incorporating W2NixCo(1-x)B2 compounds with controlled Ni content (x=0.1-0.6), TiB2 in specific amounts (0.5-5.0 wt%), and Al compounds. These parameter changes maintain structural stability through the robust W-Co-Ni-B matrix while introducing elements that enhance chemical bonding to ceramic coatings.
Solution Approach 2:
The composite binder phase combines refractory W-based compounds for structural stability with TiB2 and Al compounds that provide interfacial bonding capabilities. This multi-component composite system simultaneously achieves structural integrity and improved adhesiveness to ceramic coating films.
3Productivity
If high bias voltage is applied in PVD method to improve coating deposition, then deposition efficiency is improved, but adhesiveness deteriorates
Solution Approach 1:
The invention changes the surface chemical composition parameters of the cBN sintered body by incorporating specific binder phase compounds. This creates a surface chemistry that is more tolerant to high bias voltage PVD conditions while maintaining or improving adhesiveness, allowing efficient deposition without the usual adhesion penalty.
Solution Approach 2:
The optimized binder phase acts as an intermediary layer between the cBN sintered body and the ceramic coating film deposited by PVD. This intermediary composition facilitates better stress distribution and chemical bonding during high bias voltage deposition, preventing adhesion failure even under aggressive deposition conditions.
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 modified cBN sintered body demonstrates improved adhesiveness to ceramic coatings, extending tool life and reducing processing costs by preventing peeling and defects during cutting and grinding of difficult-to-cut materials.
Implementation Method 1
a cBN sintered body obtained by increasing cBN content, mixing blended raw materials including a Ni source, and cBN, and sintering the mixture to produce W2NixCo(1-x)B2 in the binder phase
Data Source
AI summary
There are provided a cubic boron nitride sintered body having a surface also excellent in adhesiveness to a ceramic coating film, while having excellent wear resistance and defect resistance, and a manufacturing method thereof, and a tool. The cubic boron nitride sintered body of the present invention includes 60.0 to 90.0% by volume of cubic boron nitride, the remainder being a binder phase, wherein the binder phase contains: at least any of a nitride, a boride, and an oxide of Al; at least any of a carbide, a nitride, a carbonitride, and a boride of Ti; and a compound represented by the following formula (1):W2NixCo(1-x)B2(0.40≤x<1) (1).