Composite Structural Adhesive for High-Voltage Transducer Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional adhesives for ultrasound transducers fail to provide sufficient mechanical strength, durability, and electrical isolation, especially in high-voltage focused ultrasound applications, leading to potential delamination and arcing issues.
Innovation Solution
A composite structural adhesive comprising epoxy resin, fumed silica, and a filler such as micronized mica or bioactive glass powder, which offers high glass transition temperature, structural stability, and electrical insulation, suitable for high-voltage operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional adhesives are used for bonding transducer layers, then the basic mechanical bonding function is achieved, but the adhesive fails to provide sufficient electrical isolation to prevent arcing across bonded elements under high voltage
Solution Approach 1:
The patent employs a composite adhesive formulation consisting of epoxy resin combined with specific filler materials including aluminum oxide (Al2O3), aluminum nitride (AlN), or boron nitride (BN). These fillers provide both mechanical reinforcement and superior electrical insulation properties, enabling the adhesive to withstand high voltages (hundreds to thousands of volts) without breaking down or allowing arcing between adjacent transducer elements. The composite structure allows the adhesive to simultaneously achieve adequate mechanical bonding strength and the required electrical isolation performance.
2Reliability
If the adhesive is designed to tolerate high voltage stresses, then electrical isolation is improved, but mechanical strength and durability may be compromised
Solution Approach 1:
The adhesive formulation combines epoxy resin matrix with high dielectric constant filler materials (Al2O3, AlN, or BN) in optimized ratios. The epoxy provides flexible mechanical bonding and stress distribution, while the fillers contribute electrical insulation and structural reinforcement. This synergistic composite structure enables the adhesive to simultaneously achieve high mechanical strength for withstanding bonding stresses and superior electrical isolation for preventing arcing under high voltage conditions.
Solution Approach 2:
The patent optimizes the composition parameters of the adhesive, including the type and concentration of filler materials, to achieve the desired balance between mechanical and electrical properties. By adjusting the filler loading and selecting specific filler materials with appropriate dielectric properties, the adhesive can be tuned to provide both the required mechanical strength for structural bonding and the electrical isolation necessary for high-voltage operation without compromising either performance aspect.
Data Source
AI summary
The various implementations described herein include adhesive compositions for high-voltage focused ultrasound applications. In one aspect, an ultrasound transducer comprises a plurality of tiles. Each tile includes a first electrically conductive layer, a second electrically conductive layer, a plurality of transducer elements disposed between the first electrically conductive layer and the second electrically conductive layer, and a composite structural adhesive (a) disposed between the first electrically conductive layer and the second electrically conductive layer and (b) disposed between respective adjacent transducer elements of the plurality of transducer elements. The composite structural adhesive includes an epoxy resin, fumed silica, and a powder selected from the group consisting of: (i) micronized mica, (ii) bioactive glass powder, and (iii) micronized mica and bioactive glass powder.