ASTM C1422/C1422M-20a PDF

Full title and description

ASTM C1422/C1422M-20a — Standard Specification for Chemically Strengthened Flat Glass. This specification defines requirements, classification criteria, and test methods for flat glass that has been chemically strengthened by an ion-exchange process to produce a compressive surface layer (surface compression and case depth) for use in building, transportation, solar, electronic and display applications.

Abstract

ASTM C1422/C1422M-20a covers chemically strengthened flat glass produced by ion-exchange techniques (immersion in a molten salt bath containing larger alkali ions). The standard classifies products by laboratory measurements of surface compression and case depth rather than by modulus of rupture, and it includes test methods for measuring case depth and surface compression (including an optically guided-wave technique). Techniques excluded from this specification include ion implantation, dealkalization, etch-strengthening, and glaze coatings. The document provides SI and inch-pound unit options and notes that it does not address end-use performance or all safety concerns associated with handling or processing.

General information

• Status: Active / Published (current edition in force).
• Publication date: 2020 (designation C1422/C1422M-20a; published January 8, 2020; includes amendment dated September 29, 2020).
• Publisher: ASTM International.
• ICS / categories: 81.040.20 (Glass in building) — Flat glass and glass products.
• Edition / version: C1422/C1422M-20a (current edition, amendment “-20a”).
• Number of pages: 8 pages (standard text length).

Scope

The standard applies to chemically strengthened flat glass intended for architectural, transportation, solar, electronic/display and other applications where enhanced surface strength is required. It specifies classification criteria based on measured surface compression and case depth (depth of compression) and includes test procedures for determining those parameters. The scope excludes strengthening methods other than ion-exchange (for example, ion implantation, dealkalization, etch-strengthening, and glaze coatings) and does not attempt to address final end-use performance or workplace safety procedures.

Key topics and requirements

• Definition and classification of chemically strengthened flat glass by surface compression and case depth.
• Requirements for product identification and conformance to measured compression and case depth limits.
• Primary test methods: a laboratory method for measuring case depth and surface compression (Section 8) and an alternate optically guided-wave measurement method (Section 9).
• Referenced test methods and related ASTM standards for stress measurement and glass specifications (e.g., C770, C1279, C1036, C162, C978 and other related methods).
• Units of measurement: both SI and inch-pound systems are provided but must be used independently.
• Notes on exclusions (other strengthening techniques) and statement that end-use performance is not covered.

Typical use and users

Manufacturers and processors of chemically strengthened glass, glass specifiers, architects, façade and glazing engineers, electronics and display manufacturers (smartphones, tablets, monitors), transportation component designers, test laboratories performing glass stress and case-depth measurements, and standards or quality personnel who need to verify or specify ion-exchanged glass properties.

Related standards

Standards commonly referenced alongside C1422/C1422M-20a include ASTM C770 (measurement of glass stress — optical coefficient), C1279 (photoelastic measurement of surface/edge stresses), C1036 (specification for flat glass), C162 (terminology for glass products), C978 (photoelastic determination of residual stress), C1648 (guide for index of refraction methods), and related committee C14 flat-glass specifications (for heat-strengthened/tempered and laminated glass).

Keywords

chemically strengthened glass, ion-exchange, surface compression, case depth, depth of compression, flat glass, glass stress measurement, optically guided-wave, ASTM C1422, C1422/C1422M-20a

FAQ

Q: What is this standard?

A: ASTM C1422/C1422M-20a is the ASTM specification that defines requirements and test methods for chemically strengthened flat glass produced by ion-exchange processes, including classification by surface compression and case depth.

Q: What does it cover?

A: It covers the definition, classification, measurement methods (including an optical/guided-wave alternative), and general product requirements for ion-exchanged, chemically strengthened flat glass used in building, transportation, solar and electronic/display applications. It excludes other strengthening techniques such as ion implantation, dealkalization, etch-strengthening, and coatings.

Q: Who typically uses it?

A: Glass manufacturers and processors, test laboratories, product specifiers (architects and engineers), electronics and display manufacturers, and purchasers who require verification of surface compression and case depth for chemically strengthened flat glass.

Q: Is it current or superseded?

A: The documented edition is C1422/C1422M-20a (2020 with amendment “-20a”). As of this edition the standard is active; users should confirm whether a newer revision or work item is in progress before final procurement or specification.

Q: Is it part of a series?

A: It belongs to the ASTM Committee C14 flat-glass family of standards and is commonly used alongside other flat glass specifications and optical/stress test methods (for example C1036, C1048, C1279, C770 and related test-method standards).

Q: What are the key keywords?

A: Ion-exchange, chemically strengthened, surface compression, case depth, flat glass, glass stress, ASTM C1422.