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First Study on Fracture Toughness Testing of Silicon Nitride by Using Single Edge Precrack V-Notched Beam (SEPVNB)

Montanuniversität Leoben,

Tjokorda Gde Tirta NINDHIA

Seminar Nasional Tahunan Teknik Mesin XIV (SNTTM XIV) Banjarmasin, Kalimantan Selatan, 7-8 October 2015

Montanuniversität Leoben, AUSTRIAASEA-UNINETUniversitas Udayana

1st International Conference Material, manufacturing, Mechanical Engineering, Banjarmasin, Kalimantan Selatan, 7-8 October 2015

Tanja LUBE

Montanuniversität Leoben, AUSTRIA

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

hereWas developed as ISO standard

ISO/FDIS 23146:2008(E) Single Edge V-Notched Beam (SEVNB)

Single Edge Precrack V-Notched Beam (SEPVNB)

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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 V-Notching Process by using diamond wheel

Sharpening the notch tip by using razor blade with diamond paste

Precracking

WYK I*

I σ=2/9873.34425.1857.3358.3905.0Y 2/72/52/32/1

I α−α+α+α−α=

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