Composite Machining Guide Composite Machining For decades, the aircraft industry has utilized composite materials in multiple applications, including flight surfaces and some internal cabin parts. Unfortunately, these materials are unique to each design in their fiber layering techniques, resins, and curing processes, which creates great challenges to consistency in manufacturing and assembly. Composite materials are bonded together to form complex structural sub-assemblies that must be either assembled together or attached to other structural components, such as aluminum or titanium. This presents a unique set of challenges that requires radical new technologies. Kennametal has years of experience working with material suppliers, machine tool providers, aircraft OEMs, and parts manufacturers. We have invested substantially to better understand how to machine CFRP/CFRP and CFRP/metals combinations. Our research has led us to become a leader in this field and has resulted in many exciting innovations, like our diamond-coated drills and orbital holemaking solutions. We would like to share some of this knowledge and are pleased to present the following guide to machining composite materials — from understanding their properties to selecting the best technologies. Machining Guides • Composite Machining Guide One of the newest materials using carbon fiber and resins is called CFRP (Carbon-Fiber Reinforced Polymer). Due to attractive properties, such as weight-to-strength ratio, durability, and extreme corrosion resistance, CFRP is used mostly in primary structure applications like aircraft hull and wings.

Machining Guides • Composite Machining Guide Composite Machining Guide Characteristics of Composite Materials Composite materials are generally composed of soft, tough matrix with strong, stiff reinforcements. Fiber-reinforced polymers are the broad class of composites usually targeted. ^ Fiber Reinforcements ^ Polymer Matrix — Carbon fiber/Graphite fiber — Epoxy (high strength or high modulus) — Phenolic — Glass fibers — Polyimide — Ceramic fibers — Polyetheretherketone (PEEK) — Polymer fibers (Kevlar, Polyethylene) — Tungsten fibers • CFRP/carbon-fiber reinforced polymers (particularly...

Composite Machining Guide Types of Fiber Layout Fiber can be laid in the matrix in several different configurations. Two common examples are: • Most common method: Fiber-resin “prepregs” (tape), with one laid over top of another (each tape laid in one or several directions) and one bag/vacuum molded to form a laminate. • Other methods include bulk resin impregnation, compression molding, filament winding, pultrusion, etc. Unidirectional tape Fabric weave Tape-layered composite with each tape having unidirectional fibers in different directions. Surface Quality Rapid Tool Wear — Delamination (separation...

Composite Machining Guide Standard End Milling Tool Design for Composite Routing The standard style end mills generate cutting forces in only one direction. With a positive helix cutter, this will have the tendency to lift the workpiece while causing damage to the top edge. Workpiece damage • Delamination • Fiber pullout Machining Guides • Composite Machining Guide Delamination-free bottom surface Compression End Milling The compression-style router generates cutting forces into the top and bottom surfaces of the workpiece. These forces stabilize the cut while eliminating damage to the workpiece...

End or Face Milling Mill 1–10 The Kennametal Mill 1-10 Indexable Milling Series — Face Milling, up to 100% Engagement with PCD Inserts Ideal for applications utilizing Carbon-Fiber Reinforced Polymer (CFRP). • Aggressive ramping rates, high RPM capabilities, and a superior surface finish — time after time. • Varying axial depth of cut, meeting the challenges of a wide range of applications. • No material breakout or burr formation upon entry or exit of the workpiece. Choose the Mill 1-10 to mill 90˚ walls. Visit www.kennametal.com or contact your local Authorized Kennametal Distributor.

Composite Machining Guide Composite Milling Solutions Kennametal has the right milling solutions designed for machining difficult CFRP (Carbon-Fiber Reinforced Plastic) and non-ferrous components. Our diamond-coated (Grade KCN05™) products provide excellent tool life while producing smooth finishes with improved edge quality. Our unique geometries are free cutting, reducing heat generation and providing high quality machined surfaces. Cutters were originally designed for trimming fiberglass, but also are found to work in CFRP. Excellent temperature control while producing good surface quality....

Composite Machining Guide Compression-Style Routers • KCN05™ Features • Kennametal standard • Through hole capability • Plain shank • Through coolant • Helix angle 25° Application • Slotting and side milling • Ramping capabilities • Aerospace composites and fiberglass Compression-Style • KCN05 • Inch order number catalog number ■ Compression-Style • KCN05 • Metric order number catalog number * Through coolant available on 4-flute styles only. Machining Guides • Composite Machining Guide

Composite Machining Guide Burr-Style Routers • End Cutting • KCN05™ and K600™ Features • Kennametal standard • Plain shank • Helix angle 15° Machining Guides • Composite Machining Guide KENNAMETAL www.kennametal.com

Composite Machining Guide Down-Cut-Style Routers • KCN05™ Additional Burr-styles point styles available upon request: Machining Guides • Composite Machining Guide Down-Cut-Style Routers • KCN05 Features • Kennametal standard • Plain shank • Helix angle 25°

Composite Machining Guide Ball-End-Style Routers • KCN05™ Features • Kennametal standard • Plain shank • Helix angle 30° order number catalog number Machining Guides • Composite Machining Guide ■ Ball-End-Style • KCN05 • Metric order number catalog number KENNAMETAL www.kennametal.com