ASTM D6742/D6742M is a standard practice used to run filled-hole tension and compression strength testing on polymer matrix composite laminates. It is commonly used when a drilled hole is present and a close-tolerance pin or fastener is installed in the hole to represent a “filled-hole” condition.
This practice is typically used alongside open-hole composite tensile and compressive test methods, with added requirements for the filled-hole setup and reporting. If you need help determining whether filled-hole testing is the right approach for your laminate and joint design, talk with our team.
ASTM D6742/D6742M – Standard Practice for Filled-Hole Tension and Compression Testing of Polymer Matrix Composite Laminates
ASTM D6742/D6742M provides instructions for modifying established open-hole tension and open-hole compression testing so that filled-hole tensile strength and filled-hole compressive strength can be determined.
The practice is intended for continuous-fiber reinforced polymer matrix composite laminates that are symmetric and balanced relative to the test direction.
Quick definition
Document type: Standard practice (procedural guidance used with other test methods).
What it measures: Filled-hole tensile strength and filled-hole compressive strength of specified composite laminate forms, using a close-tolerance pin or fastener installed in the hole.
Where it fits: A supplements-and-reporting practice used with open-hole tensile and compression test methods for polymer matrix composites.
What This Standard Covers
This practice describes how to adapt open-hole composite tension and compression testing when the hole is “filled” by installing a close-tolerance fastener or pin. The practice focuses on the filled-hole condition and the additional variables that must be controlled and documented for repeatability.
Importantly, multiple filled-hole specimen details can significantly affect results, and the practice expects those details to be specified and reported (for example, hardware selection and installation approach).
Why This Standard Matters in Testing
Composite structures frequently include drilled holes and mechanical fasteners. Filled-hole strength testing provides a way to quantify how a laminate performs when a close-tolerance pin or fastener is installed, rather than evaluating an open-hole coupon alone.
Because the practice builds on existing open-hole tensile and compressive test methods, consistent execution depends on matching the appropriate base method, specimen configuration, and reporting expectations to the exact project requirement.
Common Materials, Product Types, or Applications Covered
Material class: Continuous-fiber reinforced polymer matrix composite laminates.
Laminate constraints: The practice limits applicability to laminates that are symmetric and balanced with respect to the test direction.
Typical use cases: Engineering allowables, design verification, material/process comparisons, and QA/QC programs where a filled-hole condition is specified for tensile and/or compression strength.
Common Test or Verification Workflow
Filled-hole testing to ASTM D6742/D6742M is usually executed as a modified version of open-hole tension and open-hole compression testing, with additional steps to define and control the hardware and installation condition.
- Select the appropriate base open-hole method for the loading direction (tension or compression).
- Prepare laminate coupons meeting the laminate form limitations stated by the practice and the chosen base method.
- Produce the hole and install a close-tolerance pin or fastener in a defined manner.
- Run uniaxial tension or compression to failure following the base method, while applying the filled-hole provisions and reporting expectations from this practice.
- Report results along with key filled-hole variables (hardware and installation details) so results are reproducible and comparable.
Equipment Commonly Used for This Standard
Because ASTM D6742/D6742M is a practice that supplements other composite test methods, equipment selection typically follows the base open-hole method first, then adds tooling and controls needed for the filled-hole setup.
Common equipment families: Universal testing machine (servo-electric or servo-hydraulic), calibrated load cell, appropriate composite grips and/or compression fixtures aligned to the chosen base method, and a data acquisition/control system.
Filled-hole-specific needs (application dependent): Close-tolerance pins or fasteners, defined installation tooling (for example, torque/preload tools if required by the test plan), and metrology to document hole and hardware fit.
If you are selecting load frame capacity, grips/fixtures, and hardware-handling tooling for a specific laminate thickness and test direction, you can request a detailed quote for an equipment configuration matched to your setup.
How to Read This Designation or Revision
D6742/D6742M: The combined designation indicates the practice is published with both inch-pound and SI unit conventions. In ASTM usage, the “/M” identifier is used to denote the metric (SI) companion designation.
-23 (example: D6742/D6742M-23): The suffix indicates the year of the cited edition. Always match the edition year specified by your customer, drawing, or internal qualification plan.
Units note: The standard states that SI and inch-pound values are to be treated separately, and mixing values between systems may lead to nonconformance.
Related Standards, Methods, or Frameworks
ASTM D6742/D6742M is designed to be used as a supplement to specific open-hole composite strength methods, with significance and use guidance referenced separately.
- ASTM D5766/D5766M: Open-hole tensile testing method referenced by this practice for the underlying tension test approach.
- ASTM D6484/D6484M: Open-hole compression testing method referenced by this practice for the underlying compression test approach.
- ASTM D8509: Guide referenced by this practice for significance and use guidance.
Talk to an applications engineer
For ASTM D6742/D6742M, the most important quoting details are usually the base method (tension vs. compression), laminate form and thickness range, and the specific filled-hole hardware and installation condition you need to control and report. Share your test requirement and we’ll help map it to an equipment and fixturing package—contact our team to discuss your setup.