Hinge-Type Sample Holder for Low-Temperature Brittleness Testing

Overview

The Hinge-Type Sample Holder is a precision-engineered mechanical fixture designed specifically for low-temperature brittleness testing of leather surface coatings in accordance with GB/T 22888–2021 and ISO 17233:2017. It operates on the principle of controlled mechanical bending under cryogenic conditions to determine the critical temperature at which coated leather substrates undergo brittle fracture upon hinge deformation. This device is not a standalone instrument but an integral component of standardized low-temperature embrittlement test systems—typically integrated into programmable environmental chambers (e.g., −70 °C to +50 °C range) where thermal stabilization and reproducible mechanical actuation are essential. Its hinged architecture ensures uniform angular displacement across all mounted specimens while maintaining consistent clamping force and positional repeatability—key requirements for inter-laboratory comparability and regulatory compliance.

Key Features

• Compliant hinge mechanism engineered for precise 90° bending motion without slippage or torsional deviation during thermal cycling
• Modular sample carriage accommodating up to six (6) standard specimens simultaneously, enabling high-throughput evaluation per test cycle
• Robust stainless-steel construction with passivated surface finish to resist condensation-induced corrosion in sub-zero environments
• Tool-free specimen loading via spring-loaded clamping jaws calibrated to apply 12–15 N clamping force—sufficient to prevent lateral shift yet avoid substrate compression artifacts
• Dimensionally traceable to GB/T 22888–2021 Figure 1 and ISO 17233:2017 Annex A, including exact mounting hole spacing and pivot axis alignment tolerances (±0.1 mm)
• Integrated reference marks for optical alignment verification using digital calipers or stereo microscopy during setup and audit

Sample Compatibility & Compliance

The holder accepts rectangular leather specimens measuring 90 mm × 10 mm (L × W), with thicknesses ranging from 0.5 mm to 3.0 mm—covering typical automotive upholstery, footwear, and furniture-grade coated leathers. Specimen height is constrained by chamber internal clearance; the holder’s overall footprint (130 mm × 130 mm) and mass (1.0 kg) ensure stable placement on standard chamber shelves without vibration coupling. It satisfies mechanical interface requirements for ASTM D2137–22 (Standard Test Methods for Rubber Property—Brittleness Point of Elastomers) when adapted via optional adapter plates. Full traceability documentation—including dimensional inspection reports and material certification (AISI 304 SS)—is provided with each unit to support GLP-compliant laboratory audits and ISO/IEC 17025 accreditation.

Software & Data Management

As a passive mechanical fixture, the Hinge-Type Sample Holder does not incorporate embedded electronics or firmware. However, it is fully compatible with industry-standard environmental chamber control software (e.g., Binder VISION, ESPEC WinTest, or custom LabVIEW-based systems) that log temperature ramps, dwell times, and event-triggered image capture. When used with synchronized high-speed imaging (≥500 fps), the holder enables frame-by-frame fracture onset analysis. All test parameters—including bend angle, cooling rate, and hold duration—are defined externally per method protocols and recorded in structured CSV or XML formats compliant with FDA 21 CFR Part 11 requirements when paired with validated electronic lab notebooks (ELNs) such as LabArchives or Benchling.

Applications

• Determination of cold-flex resistance for polyurethane-, acrylic-, and nitrocellulose-based leather topcoats
• Quality assurance screening of batch-to-batch consistency in OEM automotive interior trim materials
• Development-stage evaluation of novel bio-based coating formulations under accelerated thermal stress profiles
• Failure mode analysis of delamination or microcracking at the coating–substrate interface during low-temperature flexing
• Supporting technical submissions to regulatory bodies requiring ISO 17233-conformant test evidence for CE marking or REACH compliance

FAQ

Is this holder compatible with non-leather substrates such as synthetic textiles or polymer films?

Yes—provided specimens meet the 90 mm × 10 mm geometry and can be securely clamped without edge deformation. Validation per ISO 17233 Annex B is recommended for non-leather applications.
Does NYX provide calibration services or certified reference samples?

NYX supplies dimensional verification templates and torque-specification tools for user-performed functional checks. Third-party accredited calibration (e.g., ISO/IEC 17025) is available through authorized partners upon request.
Can the holder be retrofitted into existing environmental chambers from other manufacturers?

Yes—the base plate features universal M4 threaded inserts spaced at 50 mm intervals, enabling secure mounting on most commercial chamber shelves using standard hardware.