ISO 6310:2009

Overview

ISO 6310:2009 - Road vehicles - Brake linings - Compressive strain test methods - specifies standardized laboratory methods to measure the compressive displacement (compressibility) of brake linings and brake pad assemblies under load and elevated temperature. The standard covers both coupon samples cut from friction material and complete disc brake pad assemblies, and it includes procedures to assess thermal swell, pad growth, and temperature transfer of backing plates during a hot contact test.

Key topics & technical requirements

• Two alternative test methods
  • Test method A - Coupon samples / air‑brake pad: measures compressive strain (ε) by applying a unit-area contact pressure. Typical maximum contact face pressures are given (e.g., up to 8 MPa for commercial vehicle disc pads; alternatives for drum linings are listed).
  • Test method B - Hydraulic disc brake pad assembly: measures compressive deflection/compressibility (C) while simulating hydraulic line pressures (commonly 10 MPa or 16 MPa).
• Thermal (hot) test: heating platen surface temperature specified at (400 ± 10) °C to measure hot compressibility (C400), temperature transfer to backing plate (ΔT), pad thermal swell (dS) and pad thermal growth (dG).
• Test apparatus & instrumentation
  • Uniaxial compressibility test stand or load frame, loading ram/piston fixtures, heated platen, force transducer (1% full‑scale accuracy), displacement gauge (0.001 mm accuracy), thermocouples (platen TC embedded 3 mm), data acquisition and micrometer for thickness.
• Procedures & data
  • Sample conditioning at (23 ± 5) °C, 50 ± 10% RH recommended.
  • Minimum sample counts: 5 at room temperature, 3 at elevated temperature.
  • Compensate for apparatus deflection; report platen temperature, applied pressure, measured compressibility/strain, and test method used.
• Important notes
  • Results from test methods A and B are not directly comparable.
  • Test stand verification with reference samples is required; detailed reporting format and example report are included.

Applications & who uses it

ISO 6310:2009 is used by:

• Brake component manufacturers and materials suppliers for product development, material selection and quality control.
• Automotive OEMs and test laboratories for pad characterization, verifying brake pedal travel expectations, and assessing propensity for judder or noise related to pad compressibility.
• Research & development teams investigating friction material behavior under thermal loading and simulating hydraulic calliper effects.

Keywords: ISO 6310:2009, brake linings, compressive strain, compressibility test, brake pad assemblies, thermal swell, temperature transfer, disc brake pad test.

Related standards

• ISO 611 - Road vehicles - Braking vocabulary (normative reference cited in ISO 6310:2009).
• ISO 6310:2009 replaces the earlier ISO 6310:2001 (third edition prepared by ISO/TC 22/SC 2).