Linear Friction Welding
The development of Linear Friction Welding (LFW) in 1959, with further refinement in the 1980s, expanded friction welding into a broad range of new applications. Manufacturing Technology, Inc. is uniquely positioned in the aerospace market with the experience to design, manufacture and install Linear Friction Welding machines.
Linear Friction Welding is a solid-state joining process similar to rotary friction welding, in which materials are forged using frictional heat through the controlled, relative movement of two components under high contact load. However, Linear Friction Welding is distinct from rotary friction welding. Instead of rotating one work piece, the relative motion of the moving work piece is generated by a linear motion or oscillation - typically in a sine wave. The frequency and amplitude of oscillation are the energy inputs for Linear Friction Welding. The axial load (forge force) is applied perpendicular to the axis of oscillation.
The Linear Friction Welding process is very similar to the Direct Drive Friction Welding process and its four-weld cycle phases.
- Pre Weld Thrust- Part contact under load without linear reciprocating motion (oscillation)
- 1st Friction Phase- Initial contact under light load and oscillation
- 2nd Friction Phase - Axial shortening of the part while under load and oscillation
- Forge Phase - Rapid cessation of motion and application of forge-force
Linear Friction Welding was originally applied to the manufacture of blades-to-disk (blisk) and integrally bladed rotors (IBR) used in the aerospace industry. Eventually, end users would like to use this technology to repair blisks and replace blades. (Linear Friction Welding is the only process by which a hollow fan blade can be integrally attached to a fan hub without slots.) Today, Linear Friction Welding is being recognized as a rapid, low cost fabrication process for manufacturers in many industrial markets, and is becoming a go-to technology in the automotive, power generation and distribution, and structural engineering industries.
MTI offers cost-effective, in-house Linear Friction Welding at our plant in South Bend, Indiana.
- Forged-quality welds for complex geometries of nearly any metal type
Able to join non-rounded, complex part geometries, Linear Friction Welding joints are of forged-quality, with a 100-percent butt joint weld through the contact area. Dissimilar metals, even some considered incompatible or unweldable, are able to be joined with the same end-benefits of traditional rotary friction welding.
- Quick welding process meets the demands of any supply chain
The Linear Friction Welding process is at least twice - and up to 100 times - as fast as other welding techniques.
- Minimal joint preparation reduces prep time and speeds up production
Joint preparation isn't critical in the Linear Friction Welding process - machined, saw cut, and even sheared surfaces are weldable.
- Ecologically friendly and energy efficient
Linear Friction Welding is an ecologically clean process that requires no consumables - no flux, filler material or shielding gases - to run and does not emit smoke, fumes, or gases that need to be exhausted on the backend. Plus, the process is energy efficient. Power requirements for MTI's Linear Friction Welders are as much as 20 percent lower than those required for conventional welding processes.
- Defect-free welding decreases waste and saves money
By reducing the number of defective parts fabricated, your investment of time and materials is put to its best use. Since there is no melting, no solidification defects occur in Linear Friction Welding - meaning gas porosity, segregation, or slag inclusions are virtually eliminated. MTI's machine-controlled process also eliminates human error - making weld quality completely independent of an operator's skill level.
- Scalable welding sizes for any magnitude of applications
The size of an MTI Linear Friction Welder is limited only by the amount of mass that can be moved under servo-hydraulic power. The actual welding process is completely scalable to produce any size weld.
MTI has developed an entire line of Linear Friction Welding machines, including laboratory machines ranging from 10-ton to 100-ton forge force, and production blisk machines up to 100 tons of forge force. MTI is currently the only company in the world that has produced and successfully installed a production Linear Friction Welder.
MTI's Linear Friction Welding system offers the advantages of cost-effectiveness, reduced OEM manufacturing costs, and lighter weight components.
Linear Friction Welders from MTI also offer these value-added features:
- Flash Removal
- Manufacturing Cell Integration (Including Material Handling, Automatic Loading and Unloading, Robot Integration, Flash Removal, Bar Coding, Quality Control, and Part Destruction)
- Custom Design Machine Diagnostics and Maintenance Schedule for Full Preventive Maintenance
- Custom Applications