An Aerospace Manufacturing Perspective

1. Introduction to Fastener Technology Part 2 An Aerospace Manufacturing Perspective

2. Fasteners in Aviation • Fastener Overview: • Types of Fastener: • Permanent Fastening • Welding • Adhesive Bonding • Riveting • Temporary Fastening • Threaded • Non-Threaded

3. Permanent Fastening • Welding • Adhesive Bonding • Riveting

4. Welding • Fastening methods that join together two pieces of metal by melting the base metals and adding a filler material to form a pool of molten material • Can be carried out by the use of heat or pressure or both and with or without added metal.

5. Types of Welding • Most aerospace industry utilizes: • MIG Welding • TIG Welding • Friction Stir Welding (FSW)

6. MIG or GMAW Welding • Metal Inert Gas (MIG) welding / Gas Metal Arc Welding (GMAW): • Easiest welding process • Able to bond a wide range of material types and thicknesses • Easily adapted for automation and semi-automation welding applications

7. MIG or GMAW Welding • Metal Inert Gas (MIG) welding / Gas Metal Arc Welding (GMAW) Equipment: 1) Welding torch 2) Work piece 3) Power source 4) Wire feed unit 5) Electrode source 6) Shielding gas supply.

8. MIG or GMAW Welding • Metal Inert Gas (MIG) welding / Gas Metal Arc Welding (GMAW) Area: 1) Direction of travel 2) Contact tube 3) Electrode 4) Shielding gas 5) Molten weld metal 6) Solidified weld metal 7) Work piece.

9. TIG or GTAW Welding • Tungsten Inert Gas (TIG) welding sometimes referred by Gas Tungsten Arc Welding (GTAW) : • Most complicated welding process • Requires both hands to work; one hand is used for feeding a filler metal, while the other hand is use to control the welding torch. • Like GMAW, it has the ability to bond a wide range of material types

10. TIG or GTAW Welding • Equipment : • A welding torch • Constant-current welding power supply • Shielding gas source GTAW system setup

11. Friction Stir Welding (FSW) • Unique solid-state welding • Maintain the original metal characteristic • Typically used on a large piece of metal • Discovering a greater use in aerospace industry applications, such as: • Very low distortion and shrinkage • No fumes, sparks, or porosity • Repeatable • Cost and weight reduction • Improved joint quality

12. FSW process A. Two discrete metal work pieces butted together, along with the tool (with a probe). B. The progress of the tool through the joint, also showing the weld zone and the region affected by the tool shoulder.

13. Friction Stir Welding (FSW) • Used to manufacture some of the Airbus component such as the wing rib

14. Welding Geometry • Five basics types of weld joints are: • Butt Joint • Lap Joint • Corner Joint • Edge Joint • T-Joint

15. Adhesive Bonding • Benefits of Adhesive bonding • The ability to reduce significant amount of fasteners weight in the aerospace structures • Improve the aerospace aerodynamic and performance • Able to adjust rapid temperature changes, from sub-zero temperature in the stratosphere to ground-level temperatures in desert climates

16. Adhesive Bonding • Substances that are able to bond two materials together by : • Adhesion • Force between adhesive and substrate • Cohesion • Internal strength of adhesive itself.

17. Examples of Adhesive Bonding • Internal structures with lightweight honeycomb sheets

18. Riveting • Smooth cylindrical shaft with a head on one end • One of the earliest methods of fastening metal together and most popular choices in today’s applications for it is known as the most reliable fasteners • Aerospace industries use hundreds of thousands of solid rivets to assemble structural parts of an aircraft • Classic materials for aircraft rivets are aluminum, titanium, and nickel based alloys