Alumina Heat-Resistant Member With Surface Spinel Gradient
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heat-resistant ceramics lack sufficient thermal shock resistance and mechanical strength, particularly when exposed to high-temperature environments and corrosive conditions.
Innovation Solution
A heat-resistant member composed of alumina with a higher content percentage of magnesium aluminate and boron in the surface layer compared to the inner portion, enhancing thermal conductivity and mechanical strength through controlled distribution of spinel and anorthite.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If alumina is used as the main component for heat resistance, then heat resistance is improved, but thermal shock resistance is insufficient
Solution Approach 1:
The patent applies local quality by creating a surface layer with different composition than the inner portion. The surface layer contains higher content of magnesium aluminate (spinel) and boron, which provides lower thermal conductivity at the surface, while the inner portion maintains high alumina content for overall heat resistance. This gradient structure allows the surface to withstand thermal shocks better while the interior maintains thermal insulation.
Solution Approach 2:
The patent uses composite materials by combining alumina with magnesium aluminate (spinel) and boron compounds. The surface layer specifically contains spinel and boron in higher concentrations, creating a composite structure that leverages the low thermal conductivity of spinel and the melting point elevation effect of boron to improve thermal shock resistance while maintaining heat resistance through the alumina base material.
2Temperature
If alumina is used as the main component for heat resistance, then heat resistance is improved, but mechanical strength is insufficient
Solution Approach 1:
The patent applies local quality by concentrating magnesium aluminate (spinel) and boron in the surface layer while maintaining high alumina content in the inner portion. The spinel phase, with its perovskite-like structure, provides enhanced mechanical strength and toughness, particularly at the surface where it forms a protective layer that improves overall mechanical properties while the alumina interior maintains heat resistance.
3Reliability
If magnesium aluminate content is increased in the surface layer, then thermal shock resistance is improved, but composition complexity increases
Solution Approach 1:
The patent deliberately creates composition non-uniformity through local quality, with the surface layer containing higher magnesium aluminate (spinel) and boron content compared to the inner portion. This gradient composition is achieved through controlled sintering processes that promote spinel formation at the surface. The composition stability is maintained through precise control of raw material ratios and sintering conditions, ensuring reproducible thermal shock resistance without excessive complexity.
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 described composition improves thermal shock resistance and mechanical strength, allowing the heat-resistant member to withstand thermal shocks and corrosive environments effectively.
Implementation Method 1
a content percentage of the spinel in the surface layer section including a surface is higher than a content percentage of the spinel in an inner portion deeper than the surface layer section in a depth direction from the surface
Implementation Method 2
the heat-resistant member includes alumina as a main component, and magnesium aluminate and boron
Data Source
AI summary
A heat-resistant member (1) according to the present disclosure contains alumina as a main component, and magnesium aluminate and boron. The content percentage of the magnesium aluminate at the surface is higher than the content percentage of the magnesium aluminate in a surface layer section located directly below the surface.