cBN-PSZ Sintered Material With Alumina for Tougher Cutting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Cutting tools face challenges in cutting difficult-to-cut materials like centrifugal cast iron under severe conditions due to insufficient breaking resistance, as existing sintered materials lack the necessary toughness and durability.
Innovation Solution
A sintered material comprising cubic boron nitride and partially stabilized zirconia with a solid solution of alumina, where the nitrogen content is controlled within specific ranges, enhancing fracture toughness and breaking resistance for severe cutting conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If existing sintered materials are used for cutting difficult-to-cut materials under severe conditions, then cutting capability is maintained, but breaking resistance is insufficient
Solution Approach 1:
The patent employs a composite material system consisting of cubic boron nitride (cBN) particles dispersed in a partially stabilized zirconia (PSZ) matrix containing alumina solid solution. This composite structure combines the extreme hardness and wear resistance of cBN with the high fracture toughness and thermal stability of PSZ, achieving both cutting capability and breaking resistance required for severe cutting conditions.
Solution Approach 2:
The patent optimizes specific parameters including nitrogen content in the alumina solid solution (0.001-1 mass%) and alumina concentration (5-90 atomic%) to control the microstructure and properties of the PSZ matrix. These parameter changes enhance the breaking resistance while maintaining the material's ability to cut difficult-to-cut materials under severe conditions.
2Strength
If nitrogen content is increased to enhance breaking resistance, then fracture toughness improves, but excessive nitrogen may degrade material performance
Solution Approach 1:
The patent precisely controls the nitrogen content parameter within the range of 0.001-1 mass% in the alumina solid solution. This optimized parameter range allows nitrogen to enhance fracture toughness through solid solution strengthening and defect engineering, while avoiding excessive nitrogen that would create harmful defects or degrade the material's thermal and mechanical stability.
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 sintered material achieves significant breaking resistance and fracture toughness, enabling effective cutting of difficult-to-cut materials under severe conditions, with optimal nitrogen content ranges ensuring enhanced performance.
Implementation Method 1
partially stabilized zirconia with a solid solution of alumina formed therein
Data Source
AI summary
A sintered material comprises cubic boron nitride and a first material that is a partially stabilized ZrO2 with Al2O3 dispersed therein at crystal grain boundaries and/or in crystal grains, the sintered material comprising 20% by volume or more and 80% by volume or less of the cubic boron nitride, the sintered material comprising 0.001% by mass or more and 1% by mass or less of nitrogen in the first material when the first material is measured through secondary ion mass spectrometry.