The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus.
Most materials at low temperatures change their modulus and tend to become brittle. When using these materials in structural components that are likely to be subjected to impact it is important to understand their behavior at low temperatures under dynamic loading. The CRREL split Hopkinson Test Bar...
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ftdtic:ADA190599 2023-05-15T15:55:49+02:00 The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. Dutta, Piyush K Farrell, Dennis Kalafut, John COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH 1987-12 text/html http://www.dtic.mil/docs/citations/ADA190599 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA190599 en eng http://www.dtic.mil/docs/citations/ADA190599 APPROVED FOR PUBLIC RELEASE DTIC AND NTIS Miscellaneous Materials *COLD REGIONS *COMPRESSIVE PROPERTIES *DYNAMICS *ELASTIC PROPERTIES *LIGHTWEIGHT *LOW TEMPERATURE *METALS *RODS *STRESS STRAIN RELATIONS *MATERIALS BEHAVIOR COMPUTER PROGRAMS DATA ACQUISITION DYNAMIC LOADS FREEZING HIGH RATE ICE LOW COSTS MOBILIZATION PRESSURE SOILS STRAIN RATE STRUCTURAL COMPONENTS TEST METHODS WAVEFORMS PE62730A WU019 AST42 Text 1987 ftdtic 2016-02-24T15:25:02Z Most materials at low temperatures change their modulus and tend to become brittle. When using these materials in structural components that are likely to be subjected to impact it is important to understand their behavior at low temperatures under dynamic loading. The CRREL split Hopkinson Test Bar was designed and set up to conduct compressive strain rate tests (up to 1000 strains/s, i.e., in./in. per s) at low temperatures (down to -100 C). The results provide dynamic stress strain relationships of materials at low temperatures by considering the transmission of the stress wave through a test specimen sandwiched between two elastic bars. The specimen is contained in a liquid nitrogen operated cooling environment. During the test an elastic striker impacts the bar; as a result a stress wave passes down the bar. At the specimen a part of the wave is reflected and the rest is transmitted to the second bar. Strain gauges mounted on the bars record the wave shapes, which are analyzed to obtain the dynamic stress-strain relationships. The test bars are 1-1/2 in. in diameter and each is 8 ft long. The apparatus is suitable for testing light metals, plastics, composites, rocks, ice, and frozen soil. The data acquisition and analysis system are completely automatic, using software developed at CRREL, so the system provides for a rapid and low-cost method for high strain rate behavior studies of materials. Keywords: Dynamic strain, Hopkinson bar, Impact shock, Pressure bar, Strain rate, Strain wave, stress wave. Text Cold Regions Research and Engineering Laboratory Defense Technical Information Center: DTIC Technical Reports database |
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Defense Technical Information Center: DTIC Technical Reports database |
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ftdtic |
language |
English |
topic |
Miscellaneous Materials *COLD REGIONS *COMPRESSIVE PROPERTIES *DYNAMICS *ELASTIC PROPERTIES *LIGHTWEIGHT *LOW TEMPERATURE *METALS *RODS *STRESS STRAIN RELATIONS *MATERIALS BEHAVIOR COMPUTER PROGRAMS DATA ACQUISITION DYNAMIC LOADS FREEZING HIGH RATE ICE LOW COSTS MOBILIZATION PRESSURE SOILS STRAIN RATE STRUCTURAL COMPONENTS TEST METHODS WAVEFORMS PE62730A WU019 AST42 |
spellingShingle |
Miscellaneous Materials *COLD REGIONS *COMPRESSIVE PROPERTIES *DYNAMICS *ELASTIC PROPERTIES *LIGHTWEIGHT *LOW TEMPERATURE *METALS *RODS *STRESS STRAIN RELATIONS *MATERIALS BEHAVIOR COMPUTER PROGRAMS DATA ACQUISITION DYNAMIC LOADS FREEZING HIGH RATE ICE LOW COSTS MOBILIZATION PRESSURE SOILS STRAIN RATE STRUCTURAL COMPONENTS TEST METHODS WAVEFORMS PE62730A WU019 AST42 Dutta, Piyush K Farrell, Dennis Kalafut, John The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
topic_facet |
Miscellaneous Materials *COLD REGIONS *COMPRESSIVE PROPERTIES *DYNAMICS *ELASTIC PROPERTIES *LIGHTWEIGHT *LOW TEMPERATURE *METALS *RODS *STRESS STRAIN RELATIONS *MATERIALS BEHAVIOR COMPUTER PROGRAMS DATA ACQUISITION DYNAMIC LOADS FREEZING HIGH RATE ICE LOW COSTS MOBILIZATION PRESSURE SOILS STRAIN RATE STRUCTURAL COMPONENTS TEST METHODS WAVEFORMS PE62730A WU019 AST42 |
description |
Most materials at low temperatures change their modulus and tend to become brittle. When using these materials in structural components that are likely to be subjected to impact it is important to understand their behavior at low temperatures under dynamic loading. The CRREL split Hopkinson Test Bar was designed and set up to conduct compressive strain rate tests (up to 1000 strains/s, i.e., in./in. per s) at low temperatures (down to -100 C). The results provide dynamic stress strain relationships of materials at low temperatures by considering the transmission of the stress wave through a test specimen sandwiched between two elastic bars. The specimen is contained in a liquid nitrogen operated cooling environment. During the test an elastic striker impacts the bar; as a result a stress wave passes down the bar. At the specimen a part of the wave is reflected and the rest is transmitted to the second bar. Strain gauges mounted on the bars record the wave shapes, which are analyzed to obtain the dynamic stress-strain relationships. The test bars are 1-1/2 in. in diameter and each is 8 ft long. The apparatus is suitable for testing light metals, plastics, composites, rocks, ice, and frozen soil. The data acquisition and analysis system are completely automatic, using software developed at CRREL, so the system provides for a rapid and low-cost method for high strain rate behavior studies of materials. Keywords: Dynamic strain, Hopkinson bar, Impact shock, Pressure bar, Strain rate, Strain wave, stress wave. |
author2 |
COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH |
format |
Text |
author |
Dutta, Piyush K Farrell, Dennis Kalafut, John |
author_facet |
Dutta, Piyush K Farrell, Dennis Kalafut, John |
author_sort |
Dutta, Piyush K |
title |
The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
title_short |
The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
title_full |
The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
title_fullStr |
The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
title_full_unstemmed |
The CRREL (Cold Regions Research and Engineering Laboratory) Hopkinson Bar Apparatus. |
title_sort |
crrel (cold regions research and engineering laboratory) hopkinson bar apparatus. |
publishDate |
1987 |
url |
http://www.dtic.mil/docs/citations/ADA190599 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA190599 |
genre |
Cold Regions Research and Engineering Laboratory |
genre_facet |
Cold Regions Research and Engineering Laboratory |
op_source |
DTIC AND NTIS |
op_relation |
http://www.dtic.mil/docs/citations/ADA190599 |
op_rights |
APPROVED FOR PUBLIC RELEASE |
_version_ |
1766391317432107008 |