A System for Conducting Sophisticated Mechanical Tests in Situ with High Energy Synchrotron X-Rays Final Technical Report

Jeremy Weiss

关键词: ALIGNMENT;    BENDING;    COMPRESSION;    CONTROL SYSTEMS;    DESIGN;    DIFFRACTION;    ENGINEERS;    FEEDBACK;    FLEXIBILITY;    FRACTURES;    MACHINERY;    MECHANICAL TESTS;    POWER GENERATION;    SAFETY;    SHEAR;    SYNCHROTRON RADIATION;    SYNCHROTRONS;    TORSION Fracture;    Fatigue;    Mechanical Testing;    Load Frame;    X-Ray Diffraction;    Synchrotron Radiation;    In Situ Loading;   

DOI  :  10.2172/1047279
RP-ID  :  DOE-MSI-04846
PID  :  OSTI ID: 1047279
Others  :  TRN: US201217%%328

学科分类：材料科学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

This is the final technical report for the SBIR Phase I project titled 'A System for Conducting Sophisticated Mechanical Tests in Situ with High Energy Synchrotron X-Rays.' Experiments using diffraction of synchrotron radiation that help scientists understand engineering material failure modes, such as fracture and fatigue, require specialized machinery. This machinery must be able to induce these failure modes in a material specimen while adhering to strict size, weight, and geometric limitations prescribed by diffraction measurement techniques. During this Phase I project, Mechanical Solutions, Inc. (MSI) developed one such machine capable of applying uniaxial mechanical loading to a material specimen in both tension and compression, with zero backlash while transitioning between the two. Engineers currently compensate for a lack of understanding of fracture and fatigue by employing factors of safety in crucial system components. Thus, mechanical and structural parts are several times bigger, thicker, and heavier than they need to be. The scientific discoveries that result from diffraction experiments which utilize sophisticated mechanical loading devices will allow for broad material, weight, fuel, and cost savings in engineering design across all industries, while reducing the number of catastrophic failures in transportation, power generation, infrastructure, and all other engineering systems. With an existing load frame as the starting point, the research focused on two main areas: (1) the design of a specimen alignment and gripping system that enables pure uniaxial tension and compression loading (and no bending, shear, or torsion), and (2) development of a feedback control system that is adaptive and thus can maintain a load set point despite changing specimen material properties (e.g. a decreasing stiffness during yield).