The CTMA Connector

Friction Stir Welding - Workshop to be Held September 23 - 24.

The Friction Stir Welding (FSW) project team held a preliminary meeting on August 13 to begin the process of identifying the project champions and project technical themes.

FSW themes will be presented in two frameworks:

Applications projects: repair applications for the defense industry. Three repair applications were identified as candidates: a) aerospace door repair, b) crack repair, c) friction plug-welding
User group(s): the examination of joining similar and dissimilar materials, differing thicknesses of materials, computer simulation (FME) for optimal design and performance using friction stir technologies to achieve various geometries including tubes and blanks, for the commercial and defense sectors.

The next meeting will be a two day workshop jointly hosted by NCMS and NASA on September 23 and 24 at NASA in Huntsville, AL. In addition to the CTMA project planning activities, the workshop will include tech transfer briefings by NASA and FSW demonstrations including friction plug-welding equipment. A tour of NASA's Marshall Space Flight Center will also include the demonstration of the Variable Polarity Plasma Arc Welding, used to fabricate the external tanks on the shuttle.

Applications to participate in the workshop should be sent to gburkart@charter.net by September 15.

Super-hard, Chemically and Mechanically Resistant Protective Coatings

A new polymer coating system (PAMAMOS) that was discovered at Michigan Molecular Institute and is now being set up for small-level production at Dendritech, Inc. can coat most any material surface with a super-hard mechanically resistant coating. Once optimized, this coating will provide unprecedented scratch, abrasion and wear resistance, corrosion resistance, chemical warfare agent resistance, and solvent resistance. Initial costs can be reduced by the need to apply only a single coating rather than a series of heavy metal-based corrosion resistant undercoats and layer upon layer of protective primers and topcoats.

A preliminary demonstration of the potential use of PAMAMOS for hard coating applications, a stainless steel coupon was coated and cured at 140ºC for one hour. The resulting coating was transparent, adherent, scratch resistant, and tough. The coating was exposed to 20 vol.% sulfuric acid, acetone, paint remover, was immersed in saturated sodium chloride solution for hours, hung over the salt solution at 35ºC for several hours, was sandpapered, kept in a freezer for several days and spray coated with an enamel paint, which was not removed while immersed in salt solution nor by adhesive tape. Dropping one-half inch steel balls onto the coating from a height of five feet did not crack the coating. The material passed the ASTM cross hatch 180º tape peel test with no loss of adhesion. With subsequent immersion in sodium chloride solution after cutting through the coating with a razor blade, the PAMAMOS coating did not lose adhesion.

We envision a project to optimize this material for applications of interest to participants including:

Protection of steel and steel-made components
Chemical protection
Tool steel protection

Interested parties can contact Chuck Ryan at 734-995-4905.

Zn-Al Alloys

Zn-Al alloys are potentially cost and energy effective, environmentally friendly material systems for substituting several ferrous and non-ferrous alloys. With these attributes, these alloys could be used in replacement parts in repair depots. One area of interest is the use of Zn-Al alloys as bearing materials in place of more traditional materials such as bronze. The use of Equal Channel Angular Extrusion has been shown to improve the ductility and strength of Zn-Al alloys. During the process the grain size is also reduced. The project would work on materials and process development for optimizing properties to specific applications.

Interested parties can contact Chuck Ryan at 734-995-4905.