First Study on Fracture Toughness Testing of Silicon Nitride by Using Single Edge Precrack V-Notched Beam (SEPVNB).
First Study on Fracture Toughness Testing
of Silicon Nitride by Using Single Edge
Precrack V-Notched Beam (SEPVNB)
Universitas Udayana
Tjokorda Gde Tirta NINDHIA
ASEA-UNINET
Montanuniversität Leoben,
Montanuniversität Leoben,
AUSTRIA
AUSTRIA
Tanja LUBE
Seminar Nasional Tahunan Teknik Mesin XIV (SNTTM XIV)
Banjarmasin, Kalimantan Selatan, 7-8 October 2015
1st International Conference Material, manufacturing, Mechanical
Engineering, Banjarmasin, Kalimantan Selatan, 7-8 October 2015
Advance Ceramic
Why in silicon nitride ?
Gas pressure sintered ceramic containing
3 wt.% Al2O3 and 3 wt.% Y2O3
It may be worst if replacement of the bearing is needed since the location of
the turbine is at high altitude that will increase the cost of maintenance.
Fracture toughness test
methods
Will not
discussed
here
Was developed as ISO standard
ISO/FDIS 23146:2008(E)
Single Edge V-Notched Beam (SEVNB)
Compare
Single Edge Precrack V-Notched
Beam (SEPVNB)
Experimental
The advanced ceramic that will be tested should be mounted on
the ceramic tile by using glue. The glue is made from
thermoplastic that will be melt if it is heated (Fig. 1). The ceramic
tile will be sacrificed and consumable because small part will be
cut of also by the diamond wheel
Serial diamond grinding wheel, and grinding machine
Cutting the sample by using diamond wheel. The sample were glued and
released repetitively
• SEVNB, the fracture toughness conducted based on preparation of bar test
pieces (the sharp-tipped notch is machined)
– Honing the test piece using reciprocating razor blade & diamond
paste.
– Standard based valid condition: Notch-tip with radius range from1 µm
– 20 µm, under well controlled condition.
• Fracture toughness was computed in accordance to ISO/FDIS 23146 & the
value compared to the one that obtained from SCF method.
Initial VNotching
Process by
using diamond
wheel
Sharpening
the notch tip
by using
razor blade
with
diamond
paste
Precracking
K I = σ YI W
*
YI = 0.905α 1 / 2 − 3.358α 3 / 2 + 3.857α 5 / 2 + 1.4425α 7 / 2 − 3.873α9 / 2
α = a/W
Precrac result
Fracture toughness test
Result
Future testing
ACKNOWLEDGEMENTS
The author acknowledges:
1. o.Univ Prof. Dr. Robert Danzer, Assistance Prof. Dr. Tanja Lube and Mr. Ronald Binder of the Institute fur Structural und
Funktion keramik, Montanuniverssitat.
2. ASEA-UNINET
3. The Ernst Mach- nachbetreuungsstipendium (EZA, ICM-2014-07166)
Thank You
of Silicon Nitride by Using Single Edge
Precrack V-Notched Beam (SEPVNB)
Universitas Udayana
Tjokorda Gde Tirta NINDHIA
ASEA-UNINET
Montanuniversität Leoben,
Montanuniversität Leoben,
AUSTRIA
AUSTRIA
Tanja LUBE
Seminar Nasional Tahunan Teknik Mesin XIV (SNTTM XIV)
Banjarmasin, Kalimantan Selatan, 7-8 October 2015
1st International Conference Material, manufacturing, Mechanical
Engineering, Banjarmasin, Kalimantan Selatan, 7-8 October 2015
Advance Ceramic
Why in silicon nitride ?
Gas pressure sintered ceramic containing
3 wt.% Al2O3 and 3 wt.% Y2O3
It may be worst if replacement of the bearing is needed since the location of
the turbine is at high altitude that will increase the cost of maintenance.
Fracture toughness test
methods
Will not
discussed
here
Was developed as ISO standard
ISO/FDIS 23146:2008(E)
Single Edge V-Notched Beam (SEVNB)
Compare
Single Edge Precrack V-Notched
Beam (SEPVNB)
Experimental
The advanced ceramic that will be tested should be mounted on
the ceramic tile by using glue. The glue is made from
thermoplastic that will be melt if it is heated (Fig. 1). The ceramic
tile will be sacrificed and consumable because small part will be
cut of also by the diamond wheel
Serial diamond grinding wheel, and grinding machine
Cutting the sample by using diamond wheel. The sample were glued and
released repetitively
• SEVNB, the fracture toughness conducted based on preparation of bar test
pieces (the sharp-tipped notch is machined)
– Honing the test piece using reciprocating razor blade & diamond
paste.
– Standard based valid condition: Notch-tip with radius range from1 µm
– 20 µm, under well controlled condition.
• Fracture toughness was computed in accordance to ISO/FDIS 23146 & the
value compared to the one that obtained from SCF method.
Initial VNotching
Process by
using diamond
wheel
Sharpening
the notch tip
by using
razor blade
with
diamond
paste
Precracking
K I = σ YI W
*
YI = 0.905α 1 / 2 − 3.358α 3 / 2 + 3.857α 5 / 2 + 1.4425α 7 / 2 − 3.873α9 / 2
α = a/W
Precrac result
Fracture toughness test
Result
Future testing
ACKNOWLEDGEMENTS
The author acknowledges:
1. o.Univ Prof. Dr. Robert Danzer, Assistance Prof. Dr. Tanja Lube and Mr. Ronald Binder of the Institute fur Structural und
Funktion keramik, Montanuniverssitat.
2. ASEA-UNINET
3. The Ernst Mach- nachbetreuungsstipendium (EZA, ICM-2014-07166)
Thank You