50 Years of Characterizing Structural Ceramics and Glasses: Recognizing the Contributions of George Quinn: Standards/Mechanical Testing & Design
Sponsored by: ACerS
Program Organizers: Jeffrey Swab, Army Research Laboratory; Andrew Wereszczak, Oak Ridge National Laboratory
Wednesday 8:00 AM
October 12, 2022
Room: 404
Location: David L. Lawrence Convention Center
Funding support provided by: Corning Inc., 3M, Orton, and Bomas
Session Chair: Jeffrey Swab, US Army Research Laboratory; Andrew Wereszczak, Oak Ridge National Laboratory
8:00 AM Introductory Comments
8:10 AM Invited
On the Controversies during the Creation of Flexure Strength Standards MIL STD 1942 and ASTM C 1161
: George Quinn1; 1NIST
Flexural strength test standards MIL STD 1942 and ASTM C 1161 were created in the 1980s by the author while at the U.S. Army Materials Technology Laboratory in Watertown, Massachusetts. They revolutionized how the flexural strength of structural ceramics is measured. The U. S. Army Military Standard MIL STD 1942 came first in 1983. It was my first Standard and was created from scratch, unlike many standards that are clones of earlier documents. The MIL STD had as its foundation a comprehensive error analysis created by Frank Baratta. I corrected some of his analyses and used my own materials science, fractographic, and statistics know-how to craft the MIL STD. It was very controversial at the time and there were dramatic incidents and confrontations along the way. I recount a few of these that helped prepare me for the twenty-four standards that I created or coauthored over the years.
8:50 AM Invited
A Quintessential Standards Writer and the Tangible Benefits of Standards: Michael Jenkins1; Janine Gallego1; 1Bothell Engineering and Science Technologies
George Quinn has shown extraordinary leadership and technological prowess in the development and application of standards. Since the 1980’s Mr. Quinn wrote standards based on his empirical and analytical experiences first as Military standards and then transitioning these to ASTM and ISO standards. He does not stop at writing standards, he verifies and implements standards through organization/execution of round robins, development/marketing of standard reference materials and assisting/consulting in materials development. Mr. Quinn is the quintessential standards writer: meticulous in detail, but clear in thought and presentation keeping the end user and end use in mind without compromising technical rigor and high quality. Through his example as a standards writer as well as his administrative leadership, Mr. Quinn has recruited/inspired a new generation of standards writers. This presentation focuses on a keen and visionary goal of Mr. Quinn to demonstrate the importance of standards by showcasing their tangible benefits.
9:20 AM Invited
Static and Dynamic Compression Strength of Ceramics and Glasses: Jeffrey Swab1; John Pittari III1; Christopher Meredith1; 1Army Research Laboratory
The intrinsic compression strength of ceramics and glasses can be difficult to determine. The specimen geometry and test fixture, if not properly designed, can result in the generation of undesirable tensile stresses that can lead to misleadingly low strength values. Since compression strength is a parameter in numerous modeling and simulation packages used to predict impact performance it is imperative that it is properly measured. A variety of ceramics and glasses were machined into a dumbbell-shaped specimen that was designed to increase the likelihood of fracture initiating in the gage section. Quasi-static experiments were performed using a screw-driven load frame while a split-Hopkinson pressure bar system was used for high-strain rate experiments. High speed imaging recorded the fracture process in all tests. This presentation will summarize the results to date on boron carbide, silicon carbide, and alumina, as well as materials such as spinel and AlON and a few glasses.
9:50 AM Invited
Advanced Proof Testing for Structural Ceramics: Osama Jadaan1; Noel Nemeth2; Eric Baker3; 1University of North Florida; 2Retired; 3Connecticut Reserve Technologies
Proof testing is used to remove weak ceramic components from a manufactured batch in turn truncating the lower end of the strength-failure probability distribution. This presentation advances the early work done on proof test theory, which was limited to simple stress states, to include more general stress and material states. The theory introduced takes into account practical conditions often encountered in industrial applications such as multiaxial transient service and proof test thermomechanical loads, non-alignment (off-axis) loading between service and proof test stress states and changing material behavior with time, for both fast fracture and time-dependent failure conditions. This advanced proof test theory was coded into the integrated design code CARES/Life (Ceramic Analysis and Reliability Evaluation of Structures/Life), which is a postprocessor to commercially available Finite Element software. Examples will be presented.
10:20 AM Break
10:40 AM Invited
Sectored-flexural and Rotational-Flexural-strength Testing of Brittle Material Cylinders and Tubes: Andrew Wereszczak1; Osama Jadaan2; Emily Steiner1; Brian Oistad3; Randy Wiles1; Brett Kuwik4; 1Oak Ridge National Laboratory; 2University of North Florida; 3Saint-Gobain Research North America; 4Johns Hopkins University
Although George Quinn did not have a formal role in the development of the sectored flexural strength and rotational flexural strength test methods, George’s storied body of work and his personal commentary influenced their developments. The sectored flexural strength test measures axial tensile failure stress of brittle material cylinders and tubes and enables harvesting of multiple specimens and generation of multiple data points out of a cylinder or tube. The rotational flexure strength testing of a whole cylinder or tube superimposes continuous rotation and monotonically increasing flexure and, in principle, will desirably cause fracture to occur from the largest strength-limiting flaw on the circumference. This presentation reviews both methods, shows examples, their efficiencies, and discusses imposed effective sizes pertaining to strength-size-scaling as well as other considerations.This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy.
11:10 AM Invited
On the Elastic Isotropy of the Entropy-stabilized Oxide (Mg, Co, Ni, Cu, Zn)O Compound: Edgar Lara-Curzio1; Krishna Pitike1; Andres Marquez-Rossy1; Alexis Flores-Betancourt1; De Xin Chen1; Santosh KC1; Valentino Cooper1; 1Oak Ridge National Laboratory
The elastic properties of the entropy-stabilized oxide (Mg, Co, Ni, Cu, Zn)O compound were determined by nanoindentation and estimated using first principles calculations. Values of the indentation modulus obtained on grains with a wide range of crystallographic orientations revealed a high degree of elastic isotropy.First principles calculations predict mild elastic anisotropy for the paramagnetic structure, which decreases when the system is considered to be non-magnetic. When the antiferromagnetic state of CoO, CuO, and NiO is accounted for, a slight increase in elastic anisotropy is predicted, suggesting a coupling between magnetic ordering and the orientation dependent elastic properties. An examination of the local structure reveals that the isotropy is favored through local ionic distortions of Cu and Zn, due to their tendencies to form tenorite and wurtzite phases. The relationships between the elastic properties of the multicomponent oxide and those of its constituent binary oxides are reviewed
11:40 AM Invited
Observations in Fracture Toughness Testing of Glasses and Optical Ceramics: Jonathan Salem1; 1NASA GRC
Fracture toughness is a critical structural design parameter and an excellent metric to rank structural materials. It determines fracture strength by way of the flaws, both inherent and induced, and defines the endpoint of the slow crack growth (SCG) curve. The fracture toughnesses of glasses and structural and optical ceramics as measured by the techniques in ASTM C1421 are compared. When good metrology is employed, the results are very comparable with two exceptions: materials exhibiting crack growth resistance (R-curve) and those with low SCG exponents. For materials exhibiting R-curves, the result is a function of extension and can be minimized with short cracks. For materials with low SCG exponents, such as glasses, elimination of the corrosive media and/or increasing the stress intensity rate produces consistent results. A summary of values is given for optical materials and glasses. ASTM C1421 is applicable with some modifications.