Wave-propagation studies for improved ultrasonic testing of centrifugally cast stainless steel

Technical Report · Mon Aug 01 00:00:00 EDT 1988

OSTI ID:6904936

Rose, J L

Difficulties in the inspection of certain piping materials in the nuclear industry can come about as a result of unusual grain structure resulting from different manufacturing procedures. In centrifugally cast stainless steel, for example, grain structures of either fine or coarse grained equiaxe, or columnar-dentritic can be found. This grain structure leads to material anisotropy, which unfortunately changes were velocity in the materials as a function of angle. As a result, basic aspects of wave propagation and wave interference phenomenon are changed, leading to changes in energy velocity, beam skewing, beam splitting, unsymmetrical field profiles, unusual side lobe formations, unusual focusing and divergence etc. all causing errors in reflector detection, location, classification, sizing, and in overall imaging. Even for mild cases of anisotropy, severe beam distortion can occur. In satisfying the program goal of advancing the state-of-the-art in the ultrasonic NDE of piping materials, we launch a two phase program. The first is associated with material characterization efforts. Once this is accomplished, phase two becomes possible, this phase being associated with optimal penetrations and inspection through a known material for reliable reflector detection and analysis. 25 refs., 36 figs.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (USA); Drexel Univ., Philadelphia, PA (USA). Dept. of Mechanical Engineering and Mechanics
• OSTI ID: 6904936
• Report Number(s): EPRI-NP-5979; ON: TI88016703
• Country of Publication: United States
• Language: English

Related Subjects

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
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Nonbreeding
Light-Water Moderated
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36 MATERIALS SCIENCE
360103 -- Metals & Alloys-- Mechanical Properties
42 ENGINEERING
420500* -- Engineering-- Materials Testing
ACOUSTIC TESTING
ALLOYS
ANISOTROPY
CHROMIUM ALLOYS
CORROSION RESISTANT ALLOYS
CRYSTAL STRUCTURE
CRYSTALS
DENDRITES
FAILURES
FRACTURES
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS TESTING
MATHEMATICAL MODELS
NONDESTRUCTIVE TESTING
PIPES
PWR TYPE REACTORS
REACTORS
SOUND WAVES
STAINLESS STEELS
STEELS
TESTING
ULTRASONIC TESTING
ULTRASONIC WAVES
WATER COOLED REACTORS
WATER MODERATED REACTORS
WAVE PROPAGATION