Failure analysis of sintered B4C due to thermal shock

Spark Plasma Sintering (SPS) Technique in producing Boron Carbide is one of the top choices for defense applications. SPS can produce dense material up to 99 % of its theoretical value in a very short time (few minutes).(U, Jurgen et al.) Boron carbide is widely known for its combination of excellen...

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Main Author: Loh, Debbie Ling Man
Other Authors: Alfred Tok Iing Yoong
Format: Final Year Project
Language:English
Published: 2014
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Online Access:http://hdl.handle.net/10356/55725
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Institution: Nanyang Technological University
Language: English
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spelling sg-ntu-dr.10356-557252023-03-04T15:37:53Z Failure analysis of sintered B4C due to thermal shock Loh, Debbie Ling Man Alfred Tok Iing Yoong School of Materials Science and Engineering DRNTU::Engineering Spark Plasma Sintering (SPS) Technique in producing Boron Carbide is one of the top choices for defense applications. SPS can produce dense material up to 99 % of its theoretical value in a very short time (few minutes).(U, Jurgen et al.) Boron carbide is widely known for its combination of excellent properties of low density, high hardness, good absorption of neutrons and very stable to ionize radiation and many chemicals.(Garrett 1998) However, due to Boron Carbide’s brittleness and particularly susceptible to thermal shock, it has been a real problem, which prevents large-scale production. Therefore, this project will looked into the effects of cooling rate and press force on the mechanical properties, densification and also the ability to stay intact during sintering. SEM images of the surface morphology were also studied to analyze the inhomogeneous sintering due to fast cooling rate. Experimental results shows that although fast cooling rate due to less time taken will gives small gain size thus theoretically leading to high fracture strength. However, results shows that high cooling rate samples have a higher probability of failure. This leads us to another theory of thermal shock where difference in temperature gradient will lead to inconsistent expansion and compression, thus causing material failure. Furthermore, results also show that increase press force applied gives a lower densification and also more likely to stay intact during the sintering process This defies the actual theory of higher press force gives higher densification and we concluded that the effect of cooling rate in densification may be higher than the maximum press force applied. Lastly, the slower rate of press force applied gives higher densification due to electro-migration of ions. Bachelor of Engineering (Materials Engineering) 2014-03-24T03:26:19Z 2014-03-24T03:26:19Z 2014 2014 Final Year Project (FYP) http://hdl.handle.net/10356/55725 en Nanyang Technological University 42 p. application/pdf
institution Nanyang Technological University
building NTU Library
continent Asia
country Singapore
Singapore
content_provider NTU Library
collection DR-NTU
language English
topic DRNTU::Engineering
spellingShingle DRNTU::Engineering
Loh, Debbie Ling Man
Failure analysis of sintered B4C due to thermal shock
description Spark Plasma Sintering (SPS) Technique in producing Boron Carbide is one of the top choices for defense applications. SPS can produce dense material up to 99 % of its theoretical value in a very short time (few minutes).(U, Jurgen et al.) Boron carbide is widely known for its combination of excellent properties of low density, high hardness, good absorption of neutrons and very stable to ionize radiation and many chemicals.(Garrett 1998) However, due to Boron Carbide’s brittleness and particularly susceptible to thermal shock, it has been a real problem, which prevents large-scale production. Therefore, this project will looked into the effects of cooling rate and press force on the mechanical properties, densification and also the ability to stay intact during sintering. SEM images of the surface morphology were also studied to analyze the inhomogeneous sintering due to fast cooling rate. Experimental results shows that although fast cooling rate due to less time taken will gives small gain size thus theoretically leading to high fracture strength. However, results shows that high cooling rate samples have a higher probability of failure. This leads us to another theory of thermal shock where difference in temperature gradient will lead to inconsistent expansion and compression, thus causing material failure. Furthermore, results also show that increase press force applied gives a lower densification and also more likely to stay intact during the sintering process This defies the actual theory of higher press force gives higher densification and we concluded that the effect of cooling rate in densification may be higher than the maximum press force applied. Lastly, the slower rate of press force applied gives higher densification due to electro-migration of ions.
author2 Alfred Tok Iing Yoong
author_facet Alfred Tok Iing Yoong
Loh, Debbie Ling Man
format Final Year Project
author Loh, Debbie Ling Man
author_sort Loh, Debbie Ling Man
title Failure analysis of sintered B4C due to thermal shock
title_short Failure analysis of sintered B4C due to thermal shock
title_full Failure analysis of sintered B4C due to thermal shock
title_fullStr Failure analysis of sintered B4C due to thermal shock
title_full_unstemmed Failure analysis of sintered B4C due to thermal shock
title_sort failure analysis of sintered b4c due to thermal shock
publishDate 2014
url http://hdl.handle.net/10356/55725
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