The microscale drilling performance of a Zr-based bulk metallic glass (BMG) is investigated in this paper. Crystallization, drill temperature, axial force, spindle load (SL), acoustic emissions (AE), chip morphology, hole diameter, and entry burr height are measured and analyzed with varying cutting speed and chip load. The progression of tool wear is assessed using stereo-microscopy techniques. At small chip loads, minimum chip thickness (MCT) is observed to shift cutting mechanics from a shear-dominated to a ploughing-dominated regime. Consequently, evidence of drill instability and larger burr height are observed. As drilling temperatures rise above the glass transition temperature, the BMG thermally softens due to the transition to a super-cooled liquid state and begins to exhibit viscous characteristics. In the tool wear study using tungsten carbide microdrills, rake wear is found to dominate compared to flank wear. This is attributed to a combination of a high rate of diffusion wear on the rake face as well as lower abrasion on the flank due to the decreased hardness from thermal softening-induced viscous flow of BMG.

References

References
1.
Bakkal
,
M.
,
Liu
,
C. T.
,
Watkins
,
T. R.
,
Scattergood
,
R. O.
, and
Shih
,
A. J.
,
2004
, “
Oxidation and Crystallization of Zr-Based Bulk Metallic Glass Due to Machining
,”
Intermetallics
,
12
(
2
), pp.
195
204
.10.1016/j.intermet.2003.09.017
2.
Fujita
,
K.
,
Morishita
,
Y.
,
Nishiyama
,
N.
,
Kimura
,
H.
, and
Inoue
,
A.
,
2005
, “
Cutting Characteristics of Bulk Metallic Glass
,”
Mater. Trans.
,
46
(
12
), pp.
2856
2863
.10.2320/matertrans.46.2856
3.
Samuel
,
J.
,
Sood
,
S.
,
Kapoor
,
S. G.
, and
DeVor
,
R. E.
,
2010
, “
Micro-Scale Machining of Bulk Metallic Glass
,”
The 5th International Conference on Micro-Manufacturing
, April 5–8, 2010, Madison, WI.
4.
Bakkal
,
M.
,
Shih
,
A. J.
,
McSpadden
,
S. B.
,
Liu
,
C. T.
, and
Scattergood
,
R. O.
,
2005
, “
Light Emission, Chip Morphology, and Burr Formation in Drilling the Bulk Metallic Glass
,”
Int. J. Mach. Tools Manuf.
,
45
(
7–8
), pp.
741
752
.10.1016/j.ijmachtools.2004.11.004
5.
Stephenson
,
D. A.
, and
Agapiou
,
J. S.
,
2006
,
Metal Cutting Theory and Practice
,
CRC Press
,
Boca Raton
, FL, Chap. 21.
6.
KT-0200-S Micro-Drill Schematic, Available at: http://www.pmtnow.com
7.
Montgomery
,
D. C.
,
2001
,
Design and Analysis of Experiments
¸
John Wiley
,
New York
.
8.
Bourne
,
K. A.
, and
Kapoor
,
S. G.
,
2012
, “
Process Monitoring During Micro-Drilling via Acoustic Emission, Ultrasonic Sound, and Spindle Load Sensors
,”
International Manufacturing Science and Engineering Conference
, June 4–8, 2012, Notre Dame, IN.
9.
Park
,
K. H.
,
Beal
,
A.
,
Kim
,
D. D. W.
,
Kwon
,
P.
, and
Lantrip
,
J.
,
2011
, “
Tool Wear in Drilling of Composite/Titanium Stacks Using Carbide and Polycrystalline Diamond Tools
,”
Wear
,
271
(
11
), pp.
2826
2835
.10.1016/j.wear.2011.05.038
10.
Lee
,
K.
, and
Dornfeld
,
D. A.
,
2005
, “
Micro-Burr Formation and Miniaturization Through Process Control
,”
Precis. Eng.
,
29
(
2
), pp.
246
252
.10.1016/j.precisioneng.2004.09.002
11.
Jun
,
M. B. G.
,
Goo
,
C.
,
Malekian
,
M.
, and
Park
,
S.
,
2012
, “
A New Mechanistic Approach for Micro End Milling Force Modeling
,”
ASME J. Manuf. Sci. Eng.
,
134
(
1
), p.
011006
.10.1115/1.4005429
12.
Jalisi
,
M. N.
,
2009
, “
Microdrilling Mechanics and Performance
,” Ph.D. thesis, Northwestern University, Evanston, IL.
13.
Oxford
,
C. J.
, Jr.
,
1955
, “
On the Drilling of Metals 1: Basic Mechanics of the Process
,”
Trans. ASME
,
77
, pp.
103
114
.
14.
Kim
,
Y. J.
,
Busch
,
R.
,
Johnson
W. L.
,
Rulison
,
A. J.
, and
Rhim
,
W. K.
,
1996
, “
Experimental Determination of a Time–Temperature-Transformation Diagram of the Undercooled Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 Alloy Using the Containerless Electrostatic Levitation Processing Technique
,”
Appl. Phys. Lett.
,
68
(
8
), pp.
1057
1059
.10.1063/1.116247
15.
Bae
,
D. H.
,
Lim
,
H. K.
,
Kim
,
S. H.
,
Kim
,
D. H.
, and
Kim
,
W. T.
,
2002
, “
Mechanical Behavior of a Bulk Cu-Ti-Zr-Ni-Si-Sn Metallic Glass Forming Nano-Crystal Aggregate Bands During Deformation in the Supercooled Liquid Region
,”
Acta Mater.
,
50
(
7
), pp.
1749
1759
.10.1016/S1359-6454(02)00024-1
16.
Shen
,
J.
,
Wang
,
G.
,
Sun
,
J. F.
,
Stachurski
,
Z. H.
,
Yan
,
C.
,
Ye
,
L.
, and
Zhou
,
B. D.
,
2005
, “
Superplastic Deformation Behavior of Zr41.25Ti13.75Ni10Cu12.5Be22.5 Bulk Metallic Glass in the Supercooled Liquid Region
.”
Intermetallics
,
13
(
1
), pp.
79
85
.10.1016/j.intermet.2004.06.008
17.
Derringer
,
G.
, and
Suich
,
R.
,
1980
, “
Simultaneous Optimization of Several Response Variables
,”
J. Quality Technol.
,
12
(
4
), pp.
214
219
.
18.
Fielitz
,
P.
,
Macht
,
M. P.
,
Naundorf
,
V.
, and
Frohberg
,
G.
,
1999
, “
Diffusion in ZrTiCuNiBe Bulk Glasses at Temperatures Around the Glass Transition
,”
J. Non-Cryst. Solids
,
250
, pp.
674
678
.10.1016/S0022-3093(99)00158-1
19.
Nouari
,
M.
,
List
,
G.
,
Girot
,
F.
, and
Gehin
,
D.
,
2005
, “
Effect of Machining Parameters and Coating on Wear Mechanisms in Dry Drilling of Aluminium Alloys
,”
Int. J. Mach. Tools Manuf.
,
45
(
12–13
), pp.
1436
1442
.10.1016/j.ijmachtools.2005.01.026
20.
El-Wardany
,
T. I.
,
Mohammed
,
E.
, and
Elbestawi
,
M. A.
,
1996
, “
Cutting Temperature of Ceramic Tools in High Speed Machining of Difficult-to-Cut Materials
,”
Int. J. Mach. Tools Manuf.
,
36
(
5
), pp.
611
634
.10.1016/0890-6955(95)00043-7
21.
Dearnley
,
P. A.
,
1985
, “
Rake and Flank Wear Mechanisms of Coated and Uncoated Cemented Carbides
,”
J. Eng. Mater. Technol.
,
107
(
1
), pp.
68
82
.10.1115/1.3225773
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