Biomedical Engineering Reference
In-Depth Information
where t is the un-deformed chip thickness (or depth of cut) and t
c
is the
measured chip thickness. The machining of bone was conducted at such a
small scale that it was difficult to measure t. Therefore r was calculated using
the equation:
tan
r
(13)
cos
sin
tan
which yields r=0.425 and therefore t=4.25 μm. This is in excellent agreement
with Merchant and Zlatin's [2] nomograph for shear angles and the calculation
can be made in confidence. Shear strain γ is found from,
Cos
(14)
Sin
Cos
(
)
γ was found to be 2.55, this can be independently verified from Merchant
and Zlatin's nomograph [2] for shear strain which yields a value of 2.51.The
cutting velocity V is found using:
V
T
(15)
td
where V is 9.1 m/s. The chip velocity is found from applying the following
equation:
Sin
V
c
(16)
Cos
(
)
where V
c
is equal to 3.9 m/s, this can also be found from
V
c
rV
(17)
The two results are in agreement with each other. The shear velocity V
s
is
given by:
VCos
V
s
(18)
Cos
(
)
