Deburring and Edge Blending for Aerospace Parts

Burrs, sharp surface edges, and surface roughness can injure workers, cause mechanical and electrical problems, and reduce the service life of components. Surface irregularities can also increase friction and wear, reduce fatigue limits, create excessive stress concentrations, and produce unwanted build-ups of plating and paint. As a recent SME blog entry explains, burr removal and edge blending are especially important in the aerospace industry, where part failure can have catastrophic consequences. 

Heat, Friction, Stress, and Strain – Burrs and Sharp Edges

In aircraft engines, the mating surfaces of moving parts must be surface-finished to minimize friction.  Excessive heat can change the properties of metal surfaces, and excessive surface roughness can cause greater material wear. Rotating parts also require a surface finish that optimizes lubrication. When more of a part’s surface comes into contact with a lubricant, there’s more heat transfer from the lubricant to the moving part. That’s why the automotive industry recommends surface finishes that retain engine oil.

In the aerospace industry, surface finishing challenges include hole polishing and chamfer blending. Sharp edges and burr holes can increase both stress and strain. If excessive strain occurs, material failure can happen because of cracking. To keep strain under the yield limit, aerospace companies need to radius edges, deburr holes, and improve surface finish. Parts manufacturers also round-off or radius sharp interior and exterior corners.

Flexible Honing for Burr Removal and Surface Finishing

Brush Research Manufacturing (BRM) supplies Flex-Hone® technology to aerospace companies, aircraft manufacturers, jet engine builders, and aviation MROs. A resilient, flexible honing tool with a soft cutting action, the BRM Flex-Hone® removes burrs, blends edges, and improves surface finish at the same time. Available in a variety of sizes and abrasive types, this cylinder honing tool is also used for chamfer blending and hole-polishing.

With their abrasive globules bonded to flexible nylon filaments, Flex-Hone® tools have a distinctive appearance that’s earned them nicknames such as ball hones and dingleberry hones.  In the aerospace industry, however, BRM’s flexible honing tools are best known for solving tough surface finishing challenges. From high-quality hole finishing at a U.S. Naval Air Station to heavy-duty scale cleaning at Sikorksy Helicopter, BRM flexible honing tools are a proven solution. 

Solving Surface Finishing Challenges

For surface finishing hard materials, BRM recommends Diamond Flex-Hone® tools.  With their resin-bonded crystals, these diamond hones are ideal for aerospace materials and space age alloys such as type 302, 304, 416 and 17-4 stainless steels; Hasteloy®, Monel®, and Inconel® 718; Titanium 6AL-4V; and specialty aluminum alloys. Versatile and easy-to-use, Flex-Hone® tools feature a double-wire metal stem that’s suitable for mounting in most machine spindles. Aircraft mechanics can also use flexible hones with electric hand drills.

For aerospace applications that require optimum lubrication, Flex-Hone® technology is also the right choice. The plateau finish that flexible honing imparts removes the peaks produced by prior and honing operations to create a flat, smooth, cross-hatched surface with oil-retaining grooves. By eliminating elevated surface areas, plateau hones  remove burrs, smooth sharp surface edges, and eliminate surface roughness.