ASTM D638-22 PDF

Full title and description

ASTM D638-22 — Standard Test Method for Tensile Properties of Plastics. This standard specifies a laboratory test method for determining the tensile properties (tensile strength, tensile modulus, elongation at break and yield, and optionally Poisson’s ratio) of unreinforced and reinforced plastic materials using standard dumbbell-shaped specimens under defined conditioning and test conditions.

Abstract

ASTM D638-22 provides procedures for preparing specimens, selecting specimen types, conditioning, and performing tensile tests to produce comparable tensile-property data for control, specification, research, and development of plastic materials. It includes guidance on specimen thickness limits, optional determination of Poisson’s ratio, and references to related test methods where appropriate.

General information

• Status: Active.
• Publication date: July 1, 2022 (current edition: D638-22).
• Publisher: ASTM International.
• ICS / categories: 83.080.01 (Plastics in general).
• Edition / version: D638-22. (Supersedes D638-14).
• Number of pages: 16 pages.

Scope

This test method covers determination of the tensile properties of unreinforced and reinforced plastics using standard dumbbell-shaped specimens tested under controlled pretreatment, temperature, humidity, and testing machine speed. It applies to materials up to 14 mm (0.55 in.) in thickness (thicker materials must be machined) and notes that thin sheeting/film less than 1.0 mm (0.04 in.) is generally covered by ASTM D882. The standard also includes the option to determine Poisson’s ratio and references other relevant test methods for special materials (for example, D3039/D3039M for high-modulus fiber-reinforced composites).

Key topics and requirements

• Specimen types and dimensions (standard dumbbell specimens; common types I–V used to represent different material behaviors and thicknesses).
• Specimen preparation and conditioning requirements to ensure repeatable results (surface finish, machining, annealing/conditioning where required).
• Test-machine and instrument requirements, including calibration, appropriate grips, and use of extensometers for accurate strain measurement.
• Test speeds and procedures tied to specimen type and expected material behavior to obtain tensile modulus, yield strength, ultimate tensile strength, and elongation at break.
• Optional determination and reporting of Poisson’s ratio at room temperature.
• Reporting conventions: units (SI preferred), specimen type and dimensions, conditioning, test speed, extensometer details, and measured properties with test uncertainty as applicable.

Typical use and users

ASTM D638-22 is commonly used by materials and mechanical engineers, quality-control laboratories, test houses, plastics manufacturers, research and development teams, and regulatory/standards bodies. Typical applications include specification verification, comparative material characterization, product development, failure analysis, and acceptance testing of plastic components and materials.

Related standards

Key related standards and documents referenced in or commonly used alongside D638 include: ASTM D882 (tensile properties of thin plastic sheeting/film), ISO 527-1 (tensile testing of plastics — general principles; similar subject matter with technical differences), ASTM D3039/D3039M (tensile properties of polymer matrix composite materials), and other ASTM test methods such as D229 and D651 for certain electrical/phenolic materials. D638-22 revises the earlier D638-14 edition.

Keywords

tensile properties, tensile strength, tensile modulus, elongation at break, Poisson’s ratio, plastics testing, specimen types, ASTM D638-22, specimen conditioning, extensometer, test method.

FAQ

Q: What is this standard?

A: ASTM D638-22 is the Standard Test Method for Tensile Properties of Plastics, a laboratory procedure used to measure tensile strength, modulus, elongation, and related tensile properties of plastic materials using standard dumbbell-shaped specimens.

Q: What does it cover?

A: It covers specimen selection, preparation and conditioning, test-machine and instrument requirements, test procedures (including speeds and extensometer use), and reporting formats for tensile tests on plastics up to 14 mm thickness; it also notes preferred alternate methods for very thin films and for certain high-modulus composites.

Q: Who typically uses it?

A: Materials engineers, QC/test laboratories, plastics manufacturers, R&D teams, and standards/regulatory bodies use D638-22 for material specification, comparison, product development, and acceptance testing.

Q: Is it current or superseded?

A: D638-22 is the current active edition (approved/published in 2022). As of February 21, 2026 the standard remains active; a related ASTM work item (WK97748) was initiated in January 2026 to consider a revision to address new specimen types for additive manufacturing, indicating ongoing maintenance rather than being superseded.

Q: Is it part of a series?

A: D638-22 is maintained by ASTM Committee D20 (Plastics), Subcommittee D20.10 (Mechanical Properties), and sits alongside other ASTM test methods for plastics (for example D882 and D3039) and international standards such as ISO 527-1 that address similar test objectives.

Q: What are the key keywords?

A: Tensile strength, tensile modulus, percent elongation, Poisson’s ratio, plastic materials, specimen conditioning, extensometer, ASTM D638-22.