The SAE MOBILUS platform will continue to be accessible and populated with high quality technical content during the coronavirus (COVID-19) pandemic. x

Your Selections

Jones, Peggy
Show Only


File Formats

Content Types








   This content is not included in your SAE MOBILUS subscription, or you are not logged in.


General Motors LLC-Peggy Jones, Margarita Thompson, Yew Sum Leong, Paul Crepeau
General Motors Technical Center India-Virupakshappa Lakkonavar, Swaroop Kavi
  • Technical Paper
  • 2020-01-1072
To be published on 2020-04-14 by SAE International in United States
The market for electric vehicles and hybrid electric vehicles is expected to grow in the coming years, which is increasing interest in design optimization of electric motors for automotive applications. Under demanding duty cycles, the moving part within a motor, the rotor, may experience varying stresses induced by centrifugal force, a necessary condition for fatigue. Rotors contain hundreds of electrical steel laminations produced by stamping, which creates a characteristic edge structure comprising rollover, shear and tear zones, plus a burr. Fatigue properties are commonly reported with specimens having polished edges. Since surface condition is known to affect fatigue strength, an experiment was conducted to determine the effect of sample preparation in stamped specimens. Tensile properties were unaffected by polishing. In contrast, polishing was shown to increase fatigue strength by approximately 10-20% in the range of 105-107 cycles to failure.
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Latest Advances in Aluminum Shape Casting

General Motors LLC-Qigui Wang, Peggy Jones, Yucong Wang, Dale Gerard
Published 2017-03-28 by SAE International in United States
With the increasing use of aluminum shape castings in structural applications in automobiles, assurance of cast product integrity and performance has become critical in both design and manufacturing. In this paper, the latest understanding of the relationship between casting quality and mechanical properties of aluminum castings is summarized. Examples of newly developed technologies for alloy design, melting and melt treatment, casting and heat treatment processes in aluminum casting are reviewed. Robust design and development of high integrity aluminum castings through an Integrated Computational Materials Engineering (ICME) approach is also discussed.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Fatigue Behavior and Life Prediction for Aluminum Castings in the Absence of Casting Flaws

SAE International Journal of Materials and Manufacturing

General Motors Company-Qigui Wang, Peggy Jones
  • Journal Article
  • 2011-01-0193
Published 2011-04-12 by SAE International in United States
Cast aluminum alloys are increasingly used in cyclically loaded automotive structural applications for light weight and fuel economy. The fatigue resistance of aluminum castings strongly depends upon the presence of casting flaws and characteristics of microstructural constituents. The existence of casting flaws significantly reduces fatigue crack initiation life. In the absence of casting flaws, however, crack initiation occurs at the fatigue-sensitive microstructural constituents. Cracking and debonding of large silicon (Si) and Fe-rich intermetallic particles and crystallographic shearing from persistent slip bands in the aluminum matrix play an important role in crack initiation. This paper presents fatigue life models for aluminum castings free of casting flaws, which complement the fatigue life models for aluminum castings containing casting flaws published in [1].
Annotation ability available