Laminated TiAlN Coating Structure for Wear-Resistant Cutting Tools
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current surface coated cutting tools, particularly those with TiAlN layers, face limitations in wear resistance and fracture resistance when processing high-speed stainless steel, leading to reduced tool life due to insufficient utilization of high hardness Al content in the coating layers.
Innovation Solution
A coated cutting tool with an alternately laminated structure comprising a first layer of (AlaTi1-a)N and a second layer of (AlbMcTi1-b-c)N, where a and b are atomic ratios within specific ranges, and the inclusion of Si or B, enhancing hardness and oxidation resistance, and a lower layer and upper layer to improve adhesion and wear resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the proportion of TiAlN layer with low Al content is increased in the coating layer, then the coating layer achieves better ductility and adhesion, but the wear resistance deteriorates due to insufficient effect of high Al content layer
Solution Approach 1:
The patent applies parameter changes by precisely controlling the Al atomic ratio in TiAlN layers to be within 0.20≤a≤0.40, and controlling layer thickness ratios and overall coating thickness to optimize the balance between adhesion and wear resistance
Solution Approach 2:
The patent uses composite materials by creating an alternately laminated structure of TiAlN layers and TiN layers, where each layer type contributes different properties: TiAlN layers provide oxidation resistance and adhesion, while TiN layers provide hardness and wear resistance
2Productivity
If the cutting speed is increased for high-speed processing, then the productivity is improved, but the tool life deteriorates due to insufficient wear resistance and fracture resistance
Solution Approach 1:
The patent employs composite materials through the alternately laminated structure of TiAlN and TiN layers, where TiAlN layers provide oxidation resistance at high temperatures while TiN layers provide hardness and wear resistance, enabling high-speed cutting with extended tool life
Solution Approach 2:
The patent applies local quality by creating regions with different compositions and properties within the coating layer, where TiAlN layers specifically address oxidation resistance at the cutting zone while TiN layers address wear resistance, allowing the coating to withstand high-speed cutting 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 coated cutting tool exhibits improved wear resistance, fracture resistance, and extended tool life by optimizing the atomic ratios and layer compositions, suppressing hexagonal crystal formation and peeling, and enhancing the adhesiveness between layers.
Implementation Method 1
suppressing hexagonal crystal formation
Implementation Method 2
enhancing the adhesiveness between layers
Implementation Method 3
enhancing hardness and oxidation resistance
Data Source
AI summary
A coated cutting tool including a substrate and a coating layer formed on the substrate, wherein the coating layer has an alternately laminated structure of a first layer and a second layer, the first layer contains a compound having a composition represented by (AlaTi1-a)N (0.80≤a≤0.95), the second layer contains a compound having a composition represented by (AlbMcTi1-b-c)N (M represents at least one of Si or B, 0.80≤b≤0.95, and 0<c≤0.20), a and b satisfy |a−b|≤0.05, and an average thickness of the alternately laminated structure is 1.0 μm or more and 10.0 μm or less.