Dr. Dwight Burford

Dr. Dwight Burford joined the Advanced Materials and Manufacturing Processes Institute (AMMPI) and the Center for Friction Stir Processings (CFSP) at UNT in September 2019 as a Research Professor.  After receiving his doctorate from the Colorado School of Mines in 1987, Dr. Burford conducted postdoctoral studies at Ohio State University.  In 1989, he joined Boeing in Wichita, Kansas, where, as an Associate Technical Fellow, he conducted research and development in metal forming, machining, welding, and heat treating.  Beginning in the fall of 2000, Dr. Burford’s R&D work in friction stir welding led to production flight hardware on 747-400F aircraft in mid-2005.  From the fall of 2005 to the summer of 2012 he directed the NIAR Advanced Joining Lab at Wichita State University (WSU), and from 2007 to 2012 he directed the WSU Site of the Center for Friction Stir Processing (CFSP), an NSF I/UCRC. Since mid-2012, Dr. Burford has worked as a metallurgical engineering consultant.

Google Scholar citations | Curriculum Vitae | email: dwight.burford [@] unt.edu

 
Current Research Projects include the following topics:

 


Submerged Bobbin Tool Tunneling Technology

An Agile Approach to Fabricating Enclosed Curvilinear Integral Channels

Submerged bobbin tools, or SBTs, are designed to form integral sub-surface channels (tunnels) within components having internal pathways for wiring, gases, fluids, powders, tubing, composites, etc. Example uses are in heat exchangers, cooling plates, vacuum tools, and structural components. Like a conventional bobbin tool (BT) used in friction stir welding (FSW), an SBT has two opposing shoulders spaced apart along the bobbin or probe section of the tool.  Unlike a conventional BT, however, an SBT is used to form enclosed internal channels by the shoulder located at the terminal end of the bobbin being submerged within the workpiece while the opposite shoulder rides along on an outer surface of the workpiece.

Similar to other BT designs, the opposing shoulders of SBT designs serve to contain a substantial portion of stirred material generated throughout the progression of the process.   As a result, process forces produced parallel to the tool’s axis of rotation are reacted between the opposing shoulders.  Compared to single-sided tool designs having one shoulder, SBT tools therefore produce relatively lower out-of-plane forces that must be supported by the fabrication equipment.  In turn, fabrication equipment for internal channel production by SBTs have reduced force and stiffness requirements compared to equipment for single-sided channeling methods.  With this innovation, then, new opportunities exist for industrial robots to produce 3-D curvilinear subsurface integral channels in complex-shaped parts.

Opportunities

As a solid state fabrication technology, SBT FSP offers new benefits in the production of components having internal channels to meet internal fluid and gas flow requirements. Due to low out-of-plane force applications, it is ideal for robotic applications, thereby opening up the possibility for producing low cost 5-axis internal pathways for wiring, fluids, gases, powders, etc.

[pdf copy]

Inventors / Technical Contacts

  • Dwight Burford
    • Research Professor
    • email: dwight.burford [@] unt.edu
  • Rajiv Mishra
    • University Distinguished Research Professor
    • email: rajiv.mishra [@] unt.edu

Patent(s) Pending

Steven Tudor, Director of Licensing
Office of Innovation and Commercialization
email: steven.tudor [@] unt.edu

 


Impact Spot Welding (ISW) Fastener System

The focus of this collaborative effort is on establishing Impact Spot Welding (ISW) as a mature production fastener system that competes directly with mechanical fasteners (rivets, etc.), resistance spot welding, and other discrete joining technologies.  It is based on the work of Professor Glenn Daehn and his research group at Ohio State University.  Preliminary data show this new joining technology can rapidly install solid-state joints which meet or exceed the performance of comparable mechanically fastened and integral joints. 

Our ultimate objective in this collaborative effort is to prepare ISW for deployment as a robust approach to producing solid-state joints at a relatively low cost in time and effort via robotic cells and other nimble platforms.  In working toward achieving this objective, we also aim to generate initial design data and draft performance standards for selected ISW joints as a function of joint thickness.

Here are some of the reasons we are focusing on developing ISW into a production-ready process:

  • As a solid-state impact joining technology, ISW rapidly and efficiently produces discrete joints between similar and dissimilar materials. 
  • Joints produced by ISW typically do not show a significant heat affected zone. 
  • High pressure shock waves intrinsic to ISW tend to reduce distortion related to residual stresses when compared to localized heat-intensive joining technologies like fusion welding and friction stir welding. 
  • Vaporizing foil actuators (VFAs) can be produced in differing shapes to offer design engineers non-conventional joint configuration options, including elongated and irregularly-shaped (non-circular) joints.
  • Solid-state lap joints can be produced by ISW between coated materials without disturbing the visual appearance of the exterior coating.  This benefit is especially noteworthy in terms of reducing the complexity of assembly sequences.

We would like to provide you with coupons joined by ISW for your evaluation as part of this program.  If you supply us with the materials to be joined, this will help ensure these ISW coupons are relevant to your interests. 

What type and size of ISW fastener(s) would benefit your company most at this time?  From your perspective, are there particular joint configurations or applications that we should focus our efforts on initially?  Or, are there particular joint sizes, stack-ups, sets of materials, types of coatings, etc., that we could set for a benchmark to begin this initiative?

Technical Contacts
  • Dwight Burford
    • University of North Texas
    • Research Professor
    • email: dwight.burford [@] unt.edu
  • Glenn Daehn
    • Ohio State University
    • Mars G. Fontana Professor of Metallurgical Engineering
    • email: daehn.1 [@] osu.edu

 


Novel Solid-State Additive Manufacturing Approach

Details coming soon!