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This content will become publicly available on November 29, 2018

Title: Enhanced Dual Confocal Measurement System

A measurement instrument utilizing dual, chromatic, confocal, distance sensors has been jointly developed by General Atomics (GA) and Sandia National Laboratories (SNL) for thickness and flatness measurement of target components used in dynamic materials properties (DMP) experiments on the SNL Z-Machine (Z). Compared to previous methods used in production of these types of targets, the tool saves time and yields a 4x reduction in thickness uncertainty which is one of the largest sources of error in equation of state (EOS) measurements critical to supporting the NNSA’s Stockpile Stewardship program and computer modeling of high energy density experiments. It has numerous differences from earlier instruments operating on the dual confocal sensor principle to accommodate DMP components including larger lateral travel, longer working distance, ability to measure flatness in addition to thickness, built-in thickness calibration standards for quickly checking calibration before and after each measurement, and streamlined operation. Thickness and flatness of 0.2mm-3.3mm thick sections of diamond machined copper and aluminum can be measured to “sub-micron” accuracy. Sections up to 6mm thick can be measured with as-yet undermined accuracy. Furthermore, samples must have one surface which is flat to within 300µm, lateral dimensions of no more than 50mm x 50mm, and heightmore » less than 40mm.« less
 [1] ;  [2] ;  [1] ;  [1] ;  [1] ;  [1]
  1. General Atomics, San Diego, CA (United States)
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Grant/Contract Number:
NA0001808; NA003525
Accepted Manuscript
Journal Name:
Fusion Science and Technology
Additional Journal Information:
Journal Volume: 73; Journal Issue: 2; Journal ID: ISSN 1536-1055
American Nuclear Society
Research Org:
General Atomics, San Diego, CA (United States)
Sponsoring Org:
USDOE National Nuclear Security Administration (NNSA)
Country of Publication:
United States
36 MATERIALS SCIENCE; Dynamic materials properties; Z-Machine; equation of state
OSTI Identifier: