Calibration and error analysis approaches for optimum use of dual radiation gauges for on-line aluminum thickness measurement

Conference · Tue Jan 01 04:00:00 EST 1991 · Transactions of the American Nuclear Society; (United States)

OSTI ID:5764901

Dobbs, C L; Szalanski, J; King, E O ^[1]; Gardner, R P; Elhentaty, W; Verghese, K ^[2]

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1. Aluminum Co. of America, Alcoa Center, PA (United States)
2. North Carolina State Univ., Raleigh (United States)

In aluminum sheet metal production, it is essential to have the capability to measure sheet thickness with an accuracy of {approximately}0.1% for many commercial alloys. Nuclear gauges provide the primary means for these measurements, but they must be designed to be sufficiently insensitive to alloy composition (and density) variations, pass-line variations, temperature variations, and statistical counting rate fluctuations. It appears that properly designed dual radiation gauges may fill this need. A new generalized calibration and use approach is presented in this paper for dual radiation gauges that is capable of the required accuracy. Basically, it consists of using accurate semiempirical mathematical models of the gauges that include composition (and density) as well as thickness. Then the nominal (or best average) composition (and density) of the alloy being measured is used in the gauge models with experimental data on standards to provide the best possible calibration by appropriate least-squares methods. After these accurate semiempirical calibration models of the dual gauges are obtained, there are several possible methods of use in actual measurement.

• OSTI ID: 5764901
• Report Number(s): CONF-910603--
• Conference Information: Journal Name: Transactions of the American Nuclear Society; (United States) Journal Volume: 63
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101 -- Metals & Alloys-- Preparation & Fabrication
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400101* -- Activation
Nuclear Reaction
Radiometric & Radiochemical Procedures
ACCURACY
ALUMINIUM
CALIBRATION
CHEMICAL COMPOSITION
DIMENSIONS
ELEMENTS
ERRORS
FABRICATION
FUNCTIONS
GAMMA RADIOGRAPHY
INDUSTRIAL RADIOGRAPHY
MATERIALS WORKING
MEASURING INSTRUMENTS
METALS
ON-LINE MEASUREMENT SYSTEMS
ON-LINE SYSTEMS
RADIOMETRIC GAGES
RESPONSE FUNCTIONS
ROLLING
SENSITIVITY
SHEETS
THICKNESS
THICKNESS GAGES