Production of the IXO glass segmented mirrors by hot slumping with pressure assistance: tests and results

Effective area requirements for the large X-ray mirror of the International X-ray Observatory (IXO) are about 3 m 2 at 1keV, 0.65 m 2 at 6 keV and 150 cm 2 at 30 keV. Because of its large dimension, the telescope cannot be realized as a monolithic structure but rather it requires the integration and assembly in the telescope optical bench of a number of basic module units, called X-ray Optical Unit (XOU). We are currently studying a method for the production of these basic units that is based on the slumping technology for the production of thin glass segmented mirrors. It foresees the implementation of a stacking integration concept based on the use of reinforcing ribs connecting the glass segments in order to create very stiff structures. This paper reports on the last design of the single optical module and describe the results of FEM analyses that show how it is possible to use an innovative approach to the integration of the slumped glass foils.

show abstract

“…Final Wolter 1 shape will be obtained through the integration process. The slumping technology is described in [3].…”

Section: Advantages Of Integration Proceduresmentioning

confidence: 99%

Design of the IXO optics based on thin glass plates connected by reinforcing ribs

et al. 2011

Self Cite

View full text Add to dashboard Cite

show abstract

“…The deformation of glass could take place only under its own weight (that is by gravity) or can be actively supported by the application of additional external forces. The particular process considered in the present work is known as direct hot slumping with pressure assistance [21], and is a direct approach characterized by the active application of pressure to help the glass reaching a full contact with the mould surface, ensuring the absence of mid-frequencies deformations (in the range between few mm and a couple of cm) that degrade the optical performances. During the course of the activities, lots of improvements have been obtained in the hot slumping technology with pressure assistance.…”

Section: The Hot Slumping Process With Pressure Assistancementioning

confidence: 99%

Evaluation of the surface strength of glass plates shaped by hot slumping process

et al. 2013

Self Cite

View full text Add to dashboard Cite

Abstract:The Hot Slumping Technology is under development by several research groups in the world for the realization of grazing-incidence segmented mirrors for X-ray astronomy, based on thin glass plates shaped over a mould at temperatures above the transformation point. The performed thermal cycle and related operations might have effects on the strength characteristics of the glass, with consequences on the structural design of the elemental optical modules and consecutively on the entire X-ray optic for large astronomical missions like for example IXO and ATHENA. The mechanical strength of glass plates after they underwent the slumping process was tested through destructive double-ring tests in the Weibull statistic to assess the current IXO glass X-ray telescope design, in terms of survival probability, when subject to static and acoustic loads characteristic of the launch phase. The paper describes the activities performed and presents the obtained results.

show abstract

“…20 The deformation of glass could take place only under its own weight (that is, by gravity) or can be actively supported by the application of additional external forces. The particular process considered in the present work is known as direct hot slumping with pressure assistance, 21 and is a direct approach characterized by the active application of pressure to help the glass reach full contact with the mold surface, ensuring the absence of mid-frequencies deformations (in the range between a few millimeters and a couple of centimeters) that degrade the optical performances. During the course of the activities, many improvements have been made in the hot slumping technology with pressure assistance.…”

Section: Hot Slumping Process With Pressure Assistancementioning

confidence: 99%

Evaluation of the surface strength of glass plates shaped by hot slumping process

et al. 2014

View full text Add to dashboard Cite

Abstract. Hot slumping technology is under development by several research groups in the world for the realization of grazing-incidence segmented mirrors for x-ray astronomy, based on thin glass plates shaped over a mold at temperatures above the transformation point. The performed thermal cycle and related operations might have effects on the strength of the glass, with consequences for the structural design of the elemental optical modules and, consequently, on the entire x-ray optic for large astronomical missions such as IXO and ATHENA. The mechanical strength of glass plates after they underwent the slumping process was tested through destructive double-ring tests in the context of a study performed by the Astronomical Observatory of Brera with the collaboration of Stazione Sperimentale del Vetro and BCV Progetti. The entire study was done on more than 200 D263 Schott borosilicate glass specimens of dimensions 100 mm × 100 mm and a thickness 0.4 mm, either flat or bent at a radius of curvature of 1000 mm through the pressure-assisted hot slumping process developed by INAF-OAB. The collected experimental data have been compared with nonlinear finite element model analyses and treated with the Weibull statistic to assess the current IXO glass x-ray telescope design, in terms of survival probability, when subjected to static and acoustic loads characteristic of the launch phase. The paper describes the activities performed and presents the obtained results. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

show abstract

Production of the IXO glass segmented mirrors by hot slumping with pressure assistance: tests and results

Cited by 8 publications

References 0 publications

Design of the IXO optics based on thin glass plates connected by reinforcing ribs

Design of the IXO optics based on thin glass plates connected by reinforcing ribs

Evaluation of the surface strength of glass plates shaped by hot slumping process

Evaluation of the surface strength of glass plates shaped by hot slumping process

Contact Info

Product

Resources

About