Synchrotron Radiation Monochromator Crystal Surface Shape Control Technology

Power and power density produced by the third generation synchrotron radiation facility light source, improve two number-lever than that of the second generation synchrotron radiation facility light source due to utility of dulator,upgrading of electronic energy and degrading of electronic group scatering.High heat load resuts in preventing components performance degrading or invalid.Monochromator separates X-rays as one of central components of synchrotron radiation facility. Monochromatic component is sensitive for high heat load and lower power density resuts in great distortion of component. The focuses of the thesis with the surface distortions of the monochromator diffraction crystal which is Monochromatic component of monochromator as principal axis, are as follows:(1) The surface distortions of the monochromator diffraction crystal is one of monochromator design targets,and in order to taking measurements to maintain the slope error of crystal minnium,all kinds of factors resulting in the slope error of crystal surface are studied and analysed.The factors includes that three different kinds of distortions with general bowing,thermal bump and the change in the spacing between the crytak planes,occur in the crystal due to the high heat load, that the distortions is due to directly cooling water pressure and negative pressure of high vacuum surroundings, and that the distortions is due to mechanical fabrication and assembly hold stress et.al.(2) The surface distortions of the monochromator diffraction crystal results in rocking curve of the monochromator broadening width,performance debase,and extremely invalidation.Eergy differentiation,ransfer and diffraction efficiency,and beamline facula dispersion are studied and analysed.(3) Removing heat absorbing on crystal surface and preventing crystal distortion can improve diffraction performance.Choosing appropriate structure and cooling media,optimizing structure parameter of crystal in high heat load,releasing machining stress by CMP,taking beforehand distortion assembly,and cooling with bending et.al remove crystal surface distortions of the monochromator due to heat load.(4) The third generation synchrotron radiation facility is first developed with excessively high heat load. We design and analyse the first advanced water-cooling crystal system with develping SSRF sagitally focusing double-crystal monochromator .The diffraction crystal of two part are assembled by diffusion bonded,which solves the problem of airproof and distortion of crystal surface.The testing result on lines shows that rocking curve is excellent.