The Experts below are selected from a list of 105 Experts worldwide ranked by ideXlab platform
Jeffrey A. Hawk - One of the best experts on this subject based on the ideXlab platform.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 °C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.
Michael J. Hoffmann - One of the best experts on this subject based on the ideXlab platform.
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determination of subcritical crack growth parameters in polymer derived sioc ceramics by biaxial bending tests in water environment
Journal of the American Ceramic Society, 2010Co-Authors: K G Schell, Rainer Oberacker, Ethel C Bucharsky, Michael J. HoffmannAbstract:Polymer-derived SiOC ceramics were prepared by field-assisted sintering at 1600°C. In order to characterize this material, X-ray diffractometry, density measurements, and mechanical tests were performed. It was determined that the material is dense and predominantly amorphous with fine crystalline regions of β-SiC. A fracture toughness of 0.84 MPa · m 1/2 was determined from single edge, v-notched bending tests. Inert strength and subcritical crack growth parameters were derived from the ball-on-three-balls tests carried out at different loading rates. The inert strength of 212 MPa and the crack growth exponent n of 15 are on a similar Level as commonly expected for silica-based glasses. Because of an enhanced crack growth parameter A 0 , the crack velocity of the SiOC material at a given stress intensity Level is significantly reduced compared with silica glasses.
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Determination of Subcritical Crack Growth Parameters in Polymer‐Derived SiOC Ceramics by Biaxial Bending Tests in Water Environment
Journal of the American Ceramic Society, 2010Co-Authors: K G Schell, Rainer Oberacker, Ethel C Bucharsky, Michael J. HoffmannAbstract:Polymer-derived SiOC ceramics were prepared by field-assisted sintering at 1600°C. In order to characterize this material, X-ray diffractometry, density measurements, and mechanical tests were performed. It was determined that the material is dense and predominantly amorphous with fine crystalline regions of β-SiC. A fracture toughness of 0.84 MPa · m 1/2 was determined from single edge, v-notched bending tests. Inert strength and subcritical crack growth parameters were derived from the ball-on-three-balls tests carried out at different loading rates. The inert strength of 212 MPa and the crack growth exponent n of 15 are on a similar Level as commonly expected for silica-based glasses. Because of an enhanced crack growth parameter A 0 , the crack velocity of the SiOC material at a given stress intensity Level is significantly reduced compared with silica glasses.
K. A. Rozman - One of the best experts on this subject based on the ideXlab platform.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 °C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.
K G Schell - One of the best experts on this subject based on the ideXlab platform.
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determination of subcritical crack growth parameters in polymer derived sioc ceramics by biaxial bending tests in water environment
Journal of the American Ceramic Society, 2010Co-Authors: K G Schell, Rainer Oberacker, Ethel C Bucharsky, Michael J. HoffmannAbstract:Polymer-derived SiOC ceramics were prepared by field-assisted sintering at 1600°C. In order to characterize this material, X-ray diffractometry, density measurements, and mechanical tests were performed. It was determined that the material is dense and predominantly amorphous with fine crystalline regions of β-SiC. A fracture toughness of 0.84 MPa · m 1/2 was determined from single edge, v-notched bending tests. Inert strength and subcritical crack growth parameters were derived from the ball-on-three-balls tests carried out at different loading rates. The inert strength of 212 MPa and the crack growth exponent n of 15 are on a similar Level as commonly expected for silica-based glasses. Because of an enhanced crack growth parameter A 0 , the crack velocity of the SiOC material at a given stress intensity Level is significantly reduced compared with silica glasses.
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Determination of Subcritical Crack Growth Parameters in Polymer‐Derived SiOC Ceramics by Biaxial Bending Tests in Water Environment
Journal of the American Ceramic Society, 2010Co-Authors: K G Schell, Rainer Oberacker, Ethel C Bucharsky, Michael J. HoffmannAbstract:Polymer-derived SiOC ceramics were prepared by field-assisted sintering at 1600°C. In order to characterize this material, X-ray diffractometry, density measurements, and mechanical tests were performed. It was determined that the material is dense and predominantly amorphous with fine crystalline regions of β-SiC. A fracture toughness of 0.84 MPa · m 1/2 was determined from single edge, v-notched bending tests. Inert strength and subcritical crack growth parameters were derived from the ball-on-three-balls tests carried out at different loading rates. The inert strength of 212 MPa and the crack growth exponent n of 15 are on a similar Level as commonly expected for silica-based glasses. Because of an enhanced crack growth parameter A 0 , the crack velocity of the SiOC material at a given stress intensity Level is significantly reduced compared with silica glasses.
Jamie J Kruzic - One of the best experts on this subject based on the ideXlab platform.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 °C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.
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Fatigue Crack Growth Behavior of Nickel-base Superalloy Haynes 282 at 550-750 C
Journal of Materials Engineering and Performance, 2015Co-Authors: K. A. Rozman, Jamie J Kruzic, Jeffrey A. HawkAbstract:The fatigue crack growth rates for nickel-based superalloy Haynes 282 were measured at temperatures of 550, 650, and 750 °C using compact tension specimens with a load ratio of 0.1 and cyclic loading frequencies of 25 Hz and 0.25 Hz. Increasing the temperature from 550 to 750 °C caused the fatigue crack growth rates to increase from ~20 to 60% depending upon the applied stress intensity Level. The effect of reducing the applied loading frequency increased the fatigue crack growth rates from ~20 to 70%, also depending upon the applied stress intensity range. The crack path was observed to be transgranular for the temperatures and frequencies used during fatigue crack growth rate testing. At 750 °C, there were some indications of limited intergranular cracking excursions at both loading frequencies; however, the extent of intergranular crack growth was limited and the cause is not understood at this time.