Method for determining time-delayed changes of temperature-dependent or stress-dependent physical quantities of a glass or a glass ceramic

A glass-ceramic, time-delayed technique used in the manufacture or furnishing of glass or glass-ceramic articles

Active Publication Date: 2015-07-01
SCHOTT AG
View PDF0 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In addition, the rate of temperature change during operation ranges from <0.17K / h, thus much smaller than the typical measured rate of 36K / h

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for determining time-delayed changes of temperature-dependent or stress-dependent physical quantities of a glass or a glass ceramic
  • Method for determining time-delayed changes of temperature-dependent or stress-dependent physical quantities of a glass or a glass ceramic
  • Method for determining time-delayed changes of temperature-dependent or stress-dependent physical quantities of a glass or a glass ceramic

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0063] Within the glass transition range (transition temperature T as defined in ISO 7884-8 g Nearby) the mathematical modeling of atomic structure relaxation and stress relaxation is known and used in the mathematical modeling of thermomechanical processing methods of glass in the glass manufacturing and processing industry. Implement the model in FEM calculation software (such as ANSYS). From O.S.Narayanaswamy, "A model of structural relaxation in glass", J.Am.Ceram.Soc.54,491-498 (1971), it is known that the glass transition temperature T g A range of models that describe these structural relaxations with sufficiently good modeling quality. Structural relaxation is viewed as a transition from a non-equilibrium state of the glass structure to an equilibrium state (atomic rearrangement process).

[0064] Glasses are distinguished by the fact that non-equilibrium states can solidify. Depending on the thermal conditions (fast / slow cooling), the glass solidifies in different ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention generally relates to manufacturing or providing of glass or glass ceramic products. The invention is based on the object to allow for providing glass or glass ceramic products having very accurately characterized thermo-mechanical properties. For this purpose, a deformation of the glass or glass ceramic material is measured at least twice as a function of time with different rates of change in temperature or a mechanical stress. Based on the measurements, relaxation times and weighting factors are determined by modelling. Then, based on the relaxation times and weighting factors related to the distribution of relaxation processes occurring in the product, a time-delayed change of a temperature- dependent or stress-dependent physical quantity, such as thermal expansion or refractive index, is calculated as a function of a predefined temperature change or stress change. The invention is used for selecting during manufacturing suitable glass products exhibiting selected time-delayed properties.

Description

technical field [0001] The present invention generally relates to the manufacture or provision of glass or glass-ceramic articles. More specifically, the present invention relates to a method enabling the characterization, production and / or selection of glass and glass-ceramic articles on the basis of precisely defined thermomechanical properties. Background technique [0002] Special glass and glass-ceramic articles developed and manufactured in a custom-made manner for specific applications set very different requirements, due to the different requirements of the specific application for thermo-mechanical quantities such as thermal expansion and structural relaxation, manufactured glass or glass-ceramic components The stated requirements must be met. Examples of such custom products include telescope mirror substrates and components made of glass ceramics for microlithography. [0003] Glass ceramics exhibit low thermal expansion in different application temperature rang...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G01N25/02G01N33/38G01M11/08
CPCG01N25/02G01N33/386G01M11/005G01N19/00G02B1/00G02B5/08
Inventor 拉尔夫·让达齐克克里曼斯·库尼施思罗夫·约翰逊
Owner SCHOTT AG
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap