The effects of isothermal deformation and annealing on the microstructure of nickel-aluminum-bronze in relation to the friction stir process
Vazquez, Brian K.
McNelley, Terry R.
MetadataShow full item record
The FSP of Nickel Aluminum Bronze is a novel approach to enhance the microstructural properties of the material through a shear deformation process. This thesis examines the effect on microstructure of isothermal annealing and quenching of as-cast Nickel Aluminum Bronze and, furthermore, reports on investigation of the effects of isothermal hot rolling on microstructure of this material. Quantitative analysis of the microstructure constituents shows that heating to about 800oC results in the formation of beta by reversion of the eutectoid constituent alpha + kappaiii. Further heating in the range of 800- 1000oC results in an approximately linear decrease in the volume fraction of primary alpha and a corresponding increase in the volume fraction of beta transformation products. Isothermal rolling of NAB over this same temperature interval results in deformation of both phases and an elongated, banded distribution of alpha and beta transformation products in the middle of this interval. This suggests that local peak temperature in the stir zone of material that has been subjected to FSP may be estimated by microstructure analysis. The yield and ultimate strengths of NAB are increased and ductility is also increased when rolled material is compared to as-cast NAB. However, strength and hardness appear to be independent of prior rolling temperature.
RightsThis publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.
Showing items related by title, author, creator and subject.
Pierce, Frank Allen (Monterey, California, Naval Postgraduate School, 2004-06);The extreme strain, strain rate and temperature gradients during Friction Stir Processing (FSP) render measurement of key parameters in the stir zone infeasible with common methods. The objective of this research was to ...
The effects of isothermal deformation and annealing on the microstructure of nickel-aluminum-bronze propeller material Nabach, William A. (Monterey, California. Naval Postgraduate School, 2003-06);This thesis is a study of annealing and isothermal deformation characteristics of cast Nickel-Aluminum Bronze (NAB) in relation to Friction Stir Processing (FSP) of this material. Cast NAB is widely utilized by the U.S. ...
Microstructure characterization of friction-stir processed nickel-aluminum bronze through orientation imaging microscopy Cuevas, Assunta Mariela. (Monterey, California. Naval Postgraduate School, 2002-09);The effect of friction-stir processing (FSP) on the microstructure of a cast nickel-aluminum bronze (NAB) material has been characterized by various micro-analytical methods including orientation imaging microscopy (OIM). ...