Ceramic Member Manufacturing via Layered Metallic Paste Sintering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for manufacturing ceramic members with high void ratios in gas sensor and fuel cell devices face challenges such as incomplete sintering of electrodes, leading to reduced electrical conductivity and increased resistance, which necessitates higher drive voltages and increased electricity consumption.
Innovation Solution
A method involving the formation of a stacked compact using metallic paste layers with varying metal component concentrations, where a second metallic paste layer with a higher mass percentage of metal component M1 contains ceramic powder, allowing for diffusion and sintering, resulting in a ceramic member with a lump containing layer and metal layers that enhance void ratio and electrical properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a metal layer is formed with high void ratio by printing metal powder and firing at the same time as ceramics, then gas permeability is improved, but sintering of the electrode does not proceed sufficiently and electrical conductivity decreases
Solution Approach 1:
The patent applies preliminary action by forming the metal electrode layer before ceramic sintering, allowing the metal to sinter at lower temperatures first. The metal layer is printed and partially sintered to achieve sufficient electrical conductivity, then the ceramic is sintered at higher temperatures to create the desired void ratio and gas permeability without compromising the already-formed electrode structure.
2Ease of manufacture
If simultaneous firing of ceramics and electrode metal is performed, then manufacturing process is simplified, but electrode sintering is insufficient and resistance increases
Solution Approach 1:
The patent segments the firing process into distinct stages: first firing the metal electrode layer at a lower temperature to achieve sufficient sintering and electrical conductivity, then separately firing the ceramic at a higher temperature to achieve the desired void ratio and gas permeability. This segmentation allows each material to be processed at its optimal temperature without compromising the other.
3Reliability
If metal component concentration is increased in metallic paste layer, then electrical conductivity is improved, but void ratio decreases
Solution Approach 1:
The patent applies local quality by creating different metal component concentrations in different regions of the metallic paste layer. The layer adjacent to the ceramic green sheet has a lower metal component concentration to maintain high void ratio and gas permeability, while other regions have higher metal component concentration to ensure sufficient electrical conductivity. This spatial variation in composition allows simultaneous optimization of both electrical conductivity and gas permeability.
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
This approach enables the production of ceramic members with improved electrical conductivity and durability, reducing the need for higher drive voltages and increasing the efficiency of devices like gas sensors and fuel cells.
Implementation Method 1
As the stacked compact is fired with the mass percentage X of the metal component M1 differentiated (concentration gradient) between the metallic paste layers that adjoin via the ceramic green sheet, it is made possible to cause the metal component M1 to diffuse through the ceramic layer from a layer having higher the mass percentage X to a layer having lower the mass percentage X.
Implementation Method 2
The ceramic powder contained in the second metallic paste layer coagulates to some extent and is sintered, thereby forming a plurality of ceramic lumps.
Data Source
AI summary
A ceramic member in which the metal layers with high void ratio are sufficiently sintered to lower a residue of resin is produced. The method for manufacturing a ceramic member which comprises a step of forming a stacked compact from a plurality of metallic paste layers containing a metal component M1 that are stacked one on another via ceramic green sheets, and a step of firing the stacked compact, wherein at least one of plural metallic paste layers is formed as a second metallic paste layer that has the mass percentage X higher than that of the metallic paste layer that adjoin therewith in the stacking direction and a ceramic powder is contained in the second metallic paste layer in the step of forming the stacked compact, the mass percentage X being the proportion of the metal component M1 to the total metal content in the metallic paste layer.