At Hansen Aerospace, our chemical etching service is designed to support metallurgical evaluations to identify cracks and other issues that can compromise the integrity of aerospace components and materials.
What is Chemical Etching?
Chemical etching, sometimes called chemical milling or macro etching, is a process where a surface layer of material is selectively removed using chemical solutions.
This method enables the clear exposure of a component’s grain structure. It helps our experienced inspectors detect and analyze abnormalities such as voids, laps, or cracks which, left undetected, could compromise structural integrity or lead to in-service failure.
At Hansen Aerospace, chemical etching plays a key role in failure investigations, material evaluation, and process validation. The process is especially useful when visual confirmation of an internal structure is required without the use of mechanical cutting.
Chemical Etching Applications
Aerospace Industry
In the aerospace industry, chemical etching, also referred to as chemical milling, is used to expose internal defects in high-performance metals, including turbine disks, blades, and welded assemblies.
At Hansen Aerospace, chemical etching is utilized as part of our metallurgical evaluation process, supporting the inspection of grain structure and helping to identify laps, cracks, and other defects that could affect component integrity.
Etch Line: Enhancing the Chemical Etching Process
What is an Etch Line?
The etch line in chemical etching is a critical indicator of process control. It marks where the etching solution has interacted with the surface, forming a visible boundary where different microstructures or material phases react at varying rates.
Any inconsistencies in the etch line may indicate contamination, temperature fluctuation, or incorrect exposure time. A well-defined etch line also allows inspectors to identify shifts in grain orientation, changes in surface hardness, or the presence of welds and joints.
Importance of Etch Lines in Precision Work
An etch line is essential for documenting the consistency and effectiveness of the chemical etching process. It helps identify changes in material properties, surface treatments, and hidden structural faults that may otherwise go undetected.
Consistent etch lines are key to ensuring reliable analysis during inspections and failure investigations.
Benefits of Chemical Etching
Precision and Accuracy
Chemical etching, also known as chemical milling and macro etch, is a reliable method for metallurgical assessment where precision is critical. It enables controlled removal of surface material, revealing microstructural details that may not be visible through mechanical or visual inspection alone.
Cost-Effective for Complex Parts
The chemical etching process is well-suited for analyzing complex shapes and internal surfaces, as it is non-mechanical and carries a lower risk of distortion. It also avoids tool wear and can be easily scaled for batch testing without compromising part integrity, making it a more cost-effective testing solution.
Suitable for Various Materials
The process of chemical etching can be conducted on various metals and alloys commonly used in aerospace, including:
- Titanium
- Stainless steel
- Inconel
- Aluminum
Macro Etching is Ideal for Complex Designs
Components with intricate geometries, internal grooves, or welds can be inspected using chemical etching without causing damage.
The process reveals details that may be difficult to detect by other methods, making it especially useful for parts with coatings, treated surfaces, or weld joints.
Why Choose Hansen Aerospace?
Availability
We provide 24/7/365 access to our management team and senior executives, ensuring we’re always available to support our customers.
Partnerships
We have a proven ability to grow alongside our customers, proactively assessing their future capacity needs and ensuring a long-term, successful collaboration.
Experience and Expertise
With unmatched ultrasonic testing expertise, we are proud to have the largest concentration of IUT testing capacity for jet engine parts in the world, setting us apart as a leader in the industry.
Service
We are committed to providing exceptional customer service, as consistently praised by our clients. As a US-based NDT house, we strive to exceed expectations with every interaction.
Quality and Trust
Our commitment to quality is unwavering. With 4 decades of excellence, we have consistently passed every audit and maintained all necessary certifications, reinforcing the trust our customers place in us.
Chemical Etching FAQs
What is chemical etching?
Chemical etching, also known as chemical milling, is a controlled process used in inspection and evaluation to remove surface material using chemical solutions. It reveals grain structures, defects, or joints within the component.
What is the process of etching?
The chemical etching process involves applying a chemical solution to a metal surface to selectively dissolve material, forming an etch line that highlights structural features or inconsistencies.
What is the common chemical for etching?
Common chemicals used in chemical etching depend on the material being etched and the desired clarity of the etch line, but often include acids such as nitric or hydrochloric.
What is macro etching used for in aircraft?
Macro etching (chemical milling) is often used in the aerospace industry to expose the internal structure of crucial component parts such as turbine disks or welded assemblies. The process helps to identify cracks, laps, and other defects without causing any damage to the component.