Stephan Kallee:

Gilbert D. Sylva (died 13 September 2015) was an American engineer and friction stir welding expert.

Gil Sylva graduated at Illinois Institute of Technology. He started his career by working for 13 years from 1986 to 1999 as an engineer at Martin Marietta Astronautics in Denver, Colorado. At that time, he represented his employer in the first Group Sponsored Project that developed friction stir welding at TWI in Cambridge, UK.^{[1] [2] [3]}

Then, he worked for about two years from August 1999 to October 2001 as Senior Engineer/Scientist at the Boeing, Delta IV Facility in Decatur, Alabama. In August 2005 he moved as to Spirit AeroSystems, where he worked for more than 5 years until August 2010 as Sr. FSW Engineer MR&D. Starting in 2011, he worked as Sr. Engineer, Materials and Processes for 2 years at Eclipse Aerospace, Inc until 2013.^[3]

He died on September 13, 2015, after sustaining a head injury during a fall, from which he was unable to recover.^[4]

"Melting a material can actually decrease the strength of the weld," said Gil Sylva, who was part of the Group Sponsored Project at TWI, in which FSW was developed from laboratory curiousity to the first industrial applications.^[2]

"In FSW, you’re not adding anything to the metal that is lower in strength. Rotational and downward force plasticize the metal by generating friction heating, forming a joint with a grain structure that is finer than the parent metal, making for a virtually seamless and extremely strong joint."^[2]

• R. Edwards and G. Sylva: Recent Advances in Welding of Aluminum Alloys using a Self Reacting Pin Tool (SRPT). Approach with Application Examples. Trends in Welding Research 2005: Proceedings of the 7th International Conference, pages 191–199. AMS, 2005.
    
• G. Sylva, R. Edwards, and T. Sassa, 'A Feasibility study for self Reacting Pin Tool Welding of Thin section Aluminium', TWI's Fifth International Symposium on Friction Stir Welding, Metz, France, 14-16 September 2004.
    
• Thomas W M, Sylva G: 'Developments in Friction Stir Welding', ASM Materials Solutions 2003, Conference & Exposition, 13-15 October 2003 Pittsburgh, Pennsylvania, USA.
    
• Christner B, Hansen M, Skinner M, Sylva G. 2003. Friction stir welding system development for thin gauge aerospace structures. In: Proceedings of the 4th International Symposium on Friction Stir Welding, TWI. 2003.
    
• Christner, B.K. and Sylva, G.D., “Friction stir weld developments for aerospace applications”, International Conference on Advances in Welding Technology Joining of High Performance Materials, 6–8 November 1996, Columbus, Ohio, USA.

• Dynamic calibration assembly for a friction stir welding machine. US 8079276 B2.

1.  LinkedIn.
     
2. AAR First to Apply Advanced Welding Technology to Build Military Shelters. 29 February 2012.
     
3. NearEMPTiness, Kuru, Josve05a, Greyjoy, Sxg169, Kj cheetham, Engineerchange et al.: Gil Sylva on Wikipedia.
     
4. Tim Haynie: Gil Sylva departs.