LASER PROCESSING OF ORTHOPEDIC BIOMATERIALS - Advanced Biomaterials: Fundamentals, Processing, and Applications - page 289

expected in such bcc alloys. Similar invisibility conditions have been observed at
other locations in the same sample when imaging using g = {112}

β type two - beam

conditions [28] .
Finally, an additional feature observed in these LENS™ deposited samples
was the presence of a modulated contrast as shown in Figures 9.10a and 9.10b.
Figure 9.10a is a lower magnifi cation bright - fi eld TEM image showing the shear
bands and the modulated contrast in the background. A higher magnifi cation

(a)

500 nm

(b)

Figure 9.10. (a) Bright-fi eld
TEM image of a highly refi ned
scale modulated contrast within
the β matrix in addition to the
contrast arising from the shear
bands. (b) A higher magnifi ca-
tion image of the same modu-
lated contrast. This contrast
could possibly be associated
with fi ne scale dendrites in the β
matrix of this LENS™ deposited
alloy. [Rajarshi Banerjee et al.
Laser Deposited Ti - Nb - Zr - Ta Or-
thopedic Alloys (J. Bio. Mater.
Res., 78A (2), 2006), 298.]

100 nm