Metallic Glasses - Half Full or Half Empty

Metals and alloys are usually comfortably crystalline with a number of associated attractive and valued characteristics. What would happen if the atomic order could be compromised and more random structures formed? Very thin sections of metals can be produced with an amorphous or glassy structure if exceptionally high cooling rates can be achieved, but these are of limited utility. It was a surprise when, in the early sixties, certain alloys were identified that could be solidified in a glassy state by conventional preparation methods, such as casting. This served as the impetus to rapidly expand the search and the discovery of more and more systems that exhibited glass formability; several illustrative examples will be given.

Are glassy materials useful? Some show very attractive physical and chemical properties and are currently used for specialized applications. But, although glasses are strong and have some toughness, use as structural elements has been more elusive; it is only recently that Government funded programs have been initiated to explore the potential for engineering applications. The presentation will cover the progress made to date on one such project on Aluminum based alloys. It will describe the criteria used to formulate and design alloys, the processing methods needed to fabricate product and the properties achieved so far. Development is at an interesting stage and the jury is probably still out on the ultimate direction of this new class of materials.

Speaker’s Bio
Dr. Blackburn obtained bachelor (1958) and doctorate (1962) degrees from the University of Cambridge in the United Kingdom . Subsequently he embarked upon a long and successful industrial and government career, of over thirty-six years, with the Boeing Company, the United States Air Force and Pratt and Whitney. He recently retired from the position of Deputy Director of the Material and Process Laboratory at P&W and joined the University of Connecticut as a Research Professor.

Early technical contributions included the definition of phase transformations in titanium systems including the elucidation of the ordering reaction in titanium aluminum alloys and the definition of the nature and structure of the omega phase. New and novel test and analytical methods were developed that provided major insight into environmental cracking phenomena in light alloys. He led the initial development of titanium aluminides and invented nearly all of the first generation alloys; the crystallographic orientation between the alpha two and gamma phases is often referred to as the "Blackburn Relationship". At Pratt and Whitney he was responsible for defining material development strategy, including all titanium technology and applications, and formed close associations with the Design and Manufacturing disciplines. As manager he directed the development of over fifty technologies that are used in gas turbine engines, including powder metal disks, structural castings and super critical shafts. Dr. Blackburn is the author of over fifty publications and holds seven patents.

Current technical interests are reflected in recent contractual involvement and activity. He is presently a task leader for the Accelerated Insertion of Materials DARPA program recently awarded to P&W, and also a task manager in the Structural Amorphous Metals program awarded to the Boeing Company. Both these programs couple University led theoretical definition of property relationships to the industrial design and performance requirements for advanced materials and represent an important new trend in the field. Extensive experience in the testing and certification of structural materials is evident in the development of a new and comprehensive fatigue analysis for Titanium alloys based, in part, on the results of a recent AFOSR Contract.