Cemented Carbide Composition With Dispersed TiNbMCN for Steel Cutting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current hard materials, such as cemented carbides, lack excellent reaction resistance against steel, which is essential for cutting tools and wear-resistant applications, and existing formulations either compromise on mechanical strength or fail to disperse TiNbMCN effectively to prevent aggregation.
Innovation Solution
A cemented carbide composition featuring WC grains, TiNbMCN carbonitride grains with a core-peripheral structure, and an iron group metal binder, where the TiNbMCN is dispersed to prevent solid-state dissolution in WC crystals, achieving balanced distribution and enhanced reaction resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If TiNbMCN is added to improve reaction resistance against steel, then reaction resistance is improved, but TiNbMCN aggregates and mechanical strength deteriorates
Solution Approach 1:
The patent applies local quality by creating a core-peripheral structure where the core portion contains TiNbMCN with specific composition (X=0.1-0.2, Y=0.3-0.6, Z=0-0.02) and the peripheral portion has different composition. This localized compositional variation prevents aggregation while maintaining mechanical strength, as the core region provides reaction resistance and the peripheral region ensures structural integrity.
Solution Approach 2:
The patent uses composite materials by combining WC grains, TiNbMCN carbonitride grains with core-peripheral structure, and iron group metal binder in specific proportions. The composite structure with core-peripheral TiNbMCN grains dispersed in the matrix provides both reaction resistance against steel and mechanical strength, resolving the contradiction between these two properties.
2Reliability
If TiNbMCN is dispersed to prevent aggregation, then reaction resistance is improved, but uniform distribution is difficult to achieve
Solution Approach 1:
The patent applies parameter changes by precisely controlling the composition parameters X, Y, and Z in the TiNbMCN formula (Ti1-X-ZNbXMZC1-YNY), where X=0.1-0.2, Y=0.3-0.6, Z=0-0.02. These parameter optimizations ensure uniform dispersion of TiNbMCN grains while preventing aggregation, achieving both reaction resistance and manufacturability.
3Reliability
If core-peripheral structure is formed to prevent solid-state dissolution, then reaction resistance is improved, but manufacturing complexity increases
Solution Approach 1:
The patent applies preliminary action by forming the core-peripheral structure during the powder preparation stage before sintering. The core portion and peripheral portion are created in the powder mixture, which then maintains this structure through the sintering process. This preliminary formation of the desired structure simplifies the overall manufacturing process while achieving the goal of preventing solid-state dissolution and improving reaction resistance.
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 cemented carbide exhibits improved reaction resistance against steel while maintaining mechanical strength, with the TiNbMCN dispersion preventing aggregation and ensuring effective performance in cutting tools.
Implementation Method 1
obtaining a powder mixture by using a ball mill to mix the powder of the composite carbonitride, a WC powder, and an iron group element powder for more than or equal to 9 hours and less than or equal to 15 hours
Implementation Method 2
obtaining a powder precursor composed of the composite carbonitride by thermally treating the granulated body at more than or equal to 1800° C. under an atmosphere including nitrogen gas
Implementation Method 3
obtaining a sintered material by sintering the molded body
Data Source
AI summary
A cemented carbide includes second hard phase grains, wherein the second hard phase grains includes a core portion, and in a case where a total of 70 unit regions that are each constituted of a square having each side of 8μm are provided by successively arranging 7 unit regions in a longitudinal direction and 10 unit regions in a lateral direction in an electron microscope image of any cross section of the cemented carbide captured at a magnification of 1500×, where the total number of core portions in the total of 70 unit regions is calculated, and where a percentage of the number of core portions in each of the unit regions with respect to the total number of core portions is calculated, the number of unit regions in which the percentage is less than 0.43% or more than 2.43% is less than or equal to 10.