Friction-surfacingwith protective layers.SOLUTIONS with Effective, Practical Advice
(Sponsored Links) An Article on Friction Surfacing, including a few reference Sources, was published (2) in Issue 49 of Practical Welding Letter for September 2007. To see the article click on PWL#049. A plasticized layer with fine grained, hot-worked microstructure is deposited on the substrate without melting. Dilution is almost absent, Heat Affected Zone is narrow, no cracking or other defects are developed. Friction-surfacing is performed on specially set up dedicated machines, therefore the process is automatic and repeatable, independent on operator skill. The process is applicable on flat or circular surfaces, and also on precise locations like blade tips. Depending on the materials, different parameters, including consumable diameter, rotation speed, applied force and traverse rate must be developed for Friction-surfacing. The thickness of deposited layer is influenced by the type of consumable. Materials resisting to plastic deformation at elevated temperatures like nickel base alloys, deposit layers of 0.5 to 1 mm (0.02 to 0.04"). Austenitic stainless steel can deposit up to about 3 mm on mild steel. Aluminum alloys can leave deposits up to 6 mm thick (0.24"). The main advantage of Friction-surfacing is that it permits deposit-substrate combinations that would be incompatible with fusion welding processes. One of the disadvantages is the lack of good bond at the sides of the deposit, because of locally reduced pressure. For covering larger areas the process is repeated by depositing beads side by side, possibly machining away the weakly bonded width between runs. With proper consumables, Friction-surfacing can produce deposits presenting good wear resistant or corrosion resistant properties. The following combinations were successfully applied:
Depending on production constraints, in certain situations Friction-surfacing can be the most cost effective solution that would be advisable to explore. Any questions or comments or feedback? Write them down and send them to us by e-mail. Click on the Contact Us button in the NavBar at top left of every page.
To reach a Guide to the collection of the most important Articles from Past Issues of Practical Welding Letter, click on Welding Topics. Back Home Important AnnouncementSee our New Page on Metals Knowledge for assembling at no cost an Encyclopedia Online, a rich collection of valuable information on Metals, from expert Internet sources.
 BUILT BY:
Click on this Logo NOW! Copyright (©) 2009, by Elia E. Levi and |
