Air Data Probe Corrosion Protection via ALD Coating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Air data probes made of nickel or nickel alloys experience accelerated corrosion due to sulfur and nitrogen compounds, leading to potential failures in aircraft, and are also susceptible to foreign object damage, which can cause errors in critical readings.

Innovation Solution

A corrosion protection coating system is applied using atomic layer deposition (ALD) for a uniform, pinhole-free first layer to protect against corrosion, followed by a second layer using chemical vapor deposition (CVD), physical vapor deposition (PVD), or electroplating to shield against foreign object impact.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a corrosion barrier coating is applied to protect against sulfur and nitrogen compounds, then corrosion resistance is improved, but the coating may be susceptible to foreign object impact damage

Engineering Contradiction:

Improvecorrosion resistanceVSAvoidimpact resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The protection system is divided into two separate layers: a first layer (50-500 nm thick) applied by atomic layer deposition for corrosion resistance, and a second layer for impact protection. Each layer is optimized for its specific function, with the corrosion-resistant layer being thin and uniform, and the impact-resistant layer being thicker and more robust.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent employs a composite coating structure combining two different materials with complementary properties. The first layer uses materials suitable for corrosion protection (such as aluminum oxide, titanium oxide, or nickel phosphate), while the second layer uses materials optimized for impact resistance, creating a composite system that provides both corrosion and impact protection.

Inventive Principle:

Principle #40Composite materials

2Strength

If a thick protection layer is applied to protect against foreign object impact, then impact resistance is improved, but corrosion protection may be compromised due to pinholes or non-uniformity

Engineering Contradiction:

Improveimpact resistanceVSAvoidcorrosion resistance

Core Design Contradiction:

StrengthVSReliability

Solution Approach 1:

The protective function is segmented between two layers: the first thin layer applied by atomic layer deposition provides uniform, pinhole-free corrosion protection, while the second thicker layer provides impact protection. This segmentation allows each layer to be optimized for its specific protective function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The first corrosion-resistant layer acts as an intermediary between the substrate and the second impact-resistant layer. It provides a reliable corrosion barrier that prevents corrosive environments from reaching the substrate, while also serving as a foundation for the second layer. This intermediary layer ensures that even if the outer layer is damaged, the substrate remains protected from corrosion.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 coating system significantly extends the lifespan of air data probes by reducing corrosion and foreign object damage, ensuring reliable altitude, airspeed, and attitude readings.

Implementation Method 1

a uniform, pinhole-free first protection layer applied by atomic layer deposition (ALD) to reduce corrosion of the body

Methodology Applied

Scientific EffectAtomic layer deposition:

Implementation Method 2

a second protection layer, covering the first protection layer over the external surfaces of the body to protect the air data probe from foreign object impact damage

Methodology Applied

Scientific EffectChemical vapor deposition: Chemical Vapour Deposition

Implementation Method 3

a second protection layer, covering the first protection layer over the external surfaces of the body to protect the air data probe from foreign object impact damage

Methodology Applied

Scientific EffectPhysical vapor deposition: Physical Vapour Deposition

Implementation Method 4

a second protection layer, covering the first protection layer over the external surfaces of the body to protect the air data probe from foreign object impact damage

Methodology Applied

Scientific EffectElectroplating: Electroplating

Data Source

PatentUS11402245B2Air data probe corrosion protection

Publication Date: 2022.08.02 ROSEMOUNT AEROSPACE INC

AI summary

An air data probe with a corrosion protection coating system includes a body with an external and an internal surface and a uniform, pinhole-free first protection layer applied by atomic layer deposition (ALD) to reduce corrosion of the body, including corrosion initiated by sulfur and nitrogen compounds. The air data probe further includes a second protection layer, covering the first protection layer over the external surfaces of the body to protect the air data probe from foreign object impact damage.