The application of acoustic
emission technique for detailed understanding of dislocation dynamics,
deformation process, detection of early fatigue damage and oxidation
processes. He discovered acoustic amplification during deformation.
For the first time, Dr.
Baldev Raj has identified couplant independent ultrasonic spectral parameters
for characterization of microstructures in steels, thus paving the way for
online process monitoring applications.
Through systematic analysis
of ultrasonic data, he has brought out a new correlation between two
independent elastic properties, the ultrasonic shear wave velocity and
Poissonís ratio, in a wide variety of isotropic solid materials, such as pure
metals, ceramics, polymers and intermetallics.
Dr. Baldev Raj has applied
for the first time, anywhere in the world, an advanced impact echo technique
for assessing the integrity of the ring beam, one of the critical components
of a nuclear reactor containment building. He has extended this technique to
Delhi Iron Pillar, a monument of international significance dating back to
early 4th Century.
Dr. Baldev Raj has proposed
a two stage process of irreversible magnetic domain wall movement during
magnetization of ferromagnetic materials to correlate the Magnetic Barkhausen
emission parameters with evolving microstructures during tempering, tensile
deformation and fatigue damage.
He has developed more than
ten innovative sensors and associated instrumentation, which have found
applications and resulted in patents. An example of application is an
in-house state-of-the-art intelligent imaging system, using artificial neural
network, for automatic eddy current testing and three dimensional
characterization of defects in electrically conducting materials such as the
austenitic stainless steel plates and welds.
Dr. Baldev Raj has
developed and patented a colloidal force microscope, for in-situ measurement
of very weak forces (10-13N to 10-11N) between
individual colloidal particles that provides valuable insights into colloidal