Low-temperature endurance test

Low‑Temperature Endurance Testing Service – Comprehensive Evaluation of Material and Component Durability Under Sustained Sub‑Zero Exposure

As an ISO/IEC 17025 accredited independent testing laboratory, we offer specialised low‑temperature endurance testing services to manufacturers, engineering contractors, and quality assurance teams across the automotive, aerospace, defence, energy, electronics, and cold‑chain logistics sectors. Low‑temperature endurance – the ability of a material, component, or assembly to maintain its mechanical integrity, dimensional stability, and functional performance over prolonged exposure to sub‑zero temperatures – is a critical performance attribute for products destined for cold‑climate markets, high‑altitude operations, or refrigerated storage environments. Our test protocols simulate the sustained cold temperatures that products may experience during storage, transport, or service, evaluating changes in mechanical properties, electrical characteristics, dimensional stability, and sealing integrity. All methods are aligned with ISO, ASTM, EN, and GB/T standards, including ISO 6722 (Road vehicles – cables), ASTM D746 (Brittleness temperature of plastics), ISO 812 (Rubber – Low‑temperature brittleness), ASTM D1329 (Rubber – Low‑temperature retraction), IEC 60068‑2‑1 (Cold test), GB/T 2423.1 (Cold test), ISO 148‑1 (Charpy impact test), and ASTM E208 (Drop‑weight tear test). Our inspection and test reports are recognised by the National Medical Products Administration (NMPA), the State Administration for Market Regulation (SAMR), the Ministry of Industry and Information Technology (MIIT), and international certification bodies for product registration, type approval, and quality assurance.

Materials and Products We Regularly Test

Our low‑temperature endurance test facilities accommodate a wide range of material types, product forms, and assemblies. Typical test articles include:

Polymers and elastomers – plastics (PVC, PE, PP, PA, PC, POM), rubbers (EPDM, NBR, silicone, FKM), seals, gaskets, O‑rings, hoses, and grommets
Metals and alloys – structural steels, stainless steels, aluminium alloys, titanium alloys, and welded assemblies for cold‑climate structures
Electrical and electronic components – cables, connectors, sensors, relays, circuit boards, and control modules
Automotive components – interior trims, door seals, suspension bushings, fuel lines, braking system components, and battery packs
Construction materials – insulation panels, sealants, adhesives, waterproofing membranes, and concrete elements
Packaging materials – flexible films, rigid containers, adhesive tapes, and protective packaging for cold‑chain logistics
Aerospace and defence equipment – avionics, actuators, hydraulic components, and structural parts
Lubricants, fluids and greases – for low‑temperature pumpability and viscosity stability

Low‑Temperature Conditioning – Achieving Uniform and Stable Sub‑Zero Temperatures

Environmental chambers – temperature range from +20 °C to -70 °C (extendable to -100 °C on request) – We use computer‑controlled environmental chambers with a temperature uniformity of ±1 °C and a stability of ±0.5 °C. The chambers are equipped with forced‑air circulation to ensure uniform temperature distribution around the test specimens.
Liquid‑bath conditioning – for precise temperature control at extremely low temperatures – For small components and material specimens, we use temperature‑controlled liquid baths (using silicone oil, methanol, or liquid nitrogen‑cooled baths) to achieve temperatures down to -196 °C (liquid nitrogen). The liquid‑bath method provides faster and more uniform cooling than air‑based chambers.
Thermocouple monitoring – for verifying specimen temperature – We attach calibrated thermocouples (type T or K, accuracy ±0.2 °C) to the specimen surface to monitor the temperature during the conditioning and the testing phases, ensuring that the specimen reaches the target temperature.
Conditioning duration – ensuring thermal equilibrium – The specimens are conditioned at the specified low temperature for a minimum of 4‑24 hours (or until the specimen reaches thermal equilibrium, as confirmed by the thermocouple readings). The conditioning duration is determined by the specimen size, the thermal conductivity of the material, and the test standard.

Mechanical Property Testing at Low Temperatures – Retained Strength, Ductility and Toughness

Low‑temperature tensile testing – ASTM D638 / ISO 527 / ASTM E8 / ISO 6892‑1 – We perform tensile tests at the specified low temperature (e.g., -20 °C, -40 °C, -60 °C) using a temperature‑controlled chamber attached to the universal testing machine. We record the tensile strength (in MPa), the elongation at break (in %), and the modulus of elasticity (in MPa). The low‑temperature values are compared to the room‑temperature values to determine the retained strength and ductility. A retention of ≥ 80 % of the room‑temperature strength is typically required for most applications.
Low‑temperature flexural testing – ASTM D790 / ISO 178 / GB/T 9341 – We perform three‑point or four‑point bending tests at the specified low temperature to evaluate the flexural strength (in MPa) and the flexural modulus (in GPa). The test is used to assess the resistance of plastics and composites to cold‑induced cracking and brittle failure.
Low‑temperature impact testing – Charpy and Izod – ISO 179 / ASTM D256 / ASTM E23 / ISO 148‑1 – We perform Charpy and Izod impact tests on notched and unnotched specimens at the specified low temperature (e.g., -20 °C, -40 °C, -60 °C) to evaluate the toughness and the ductile‑to‑brittle transition behaviour. The impact strength (in kJ/m² or J/m) and the fracture appearance (percentage of shear fracture) are recorded.
Low‑temperature compression set – ASTM D395 / ISO 815 / GB/T 7759 – For elastomeric seals and gaskets, we measure the compression set (the permanent deformation after compression) at the specified low temperature. The specimen is compressed to 25 % of its original thickness, conditioned at the low temperature for 24‑72 hours, and then released. The permanent deformation is expressed as a percentage of the original thickness.
Low‑temperature brittleness temperature – ASTM D746 / ISO 812 / GB/T 1682 – We determine the temperature at which 50 % of the specimens fracture under a specified impact force (using a brittleness tester). The brittleness temperature is a measure of the material's resistance to cracking at low temperatures.

Electrical and Functional Testing at Low Temperatures – Maintaining Performance in Cold Environments

Low‑temperature electrical resistance – ASTM D257 / IEC 60093 / GB/T 1410 – We measure the electrical resistance (and volume/surface resistivity) of insulating materials and components at the specified low temperature. The resistance is measured after the specimen has been conditioned at the low temperature for a minimum of 4 hours.
Low‑temperature dielectric strength – ASTM D149 / IEC 60243‑1 / GB/T 1408 – We perform dielectric breakdown tests at the specified low temperature to assess the insulation integrity of electrical components and cable assemblies. The breakdown voltage (in kV) and the dielectric strength (in kV/mm) are recorded.
Cold start and functional check – for electronic assemblies, sensors and actuators – After conditioning at the specified low temperature (e.g., -40 °C), we perform a functional check of the component (e.g., power‑up, signal transmission, response time) to verify that it operates correctly. Any failure to start, erratic operation, or performance degradation (> 10 % change in key parameters) is recorded as a failure.
Low‑temperature cable flex and bend testing – ISO 6722 / SAE J156 / GB/T 2951.14 – We perform a flex test on cables and wire harnesses at the specified low temperature, bending the cable around a mandrel of specified diameter at a specified speed. The test assesses the resistance of the insulation and the conductor to cracking and breakage.
Low‑temperature connector and terminal performance – for assessing the contact resistance and insertion/withdrawal force – We measure the contact resistance and the insertion/withdrawal force of connectors and terminals at the specified low temperature, using a calibrated micro‑ohmmeter and a force gauge.

Dimensional Stability and Thermal Contraction – Assessing the Risk of Warping and Mismatch

Coefficient of thermal expansion (CTE) – ASTM E228 / ISO 11359‑2 / GB/T 4339 – We measure the linear thermal expansion of the material over a temperature range (e.g., -50 °C to +20 °C) using a dilatometer. The CTE (in ppm/°C or µm/m·°C) is calculated and used to predict the dimensional changes in assemblies and mating components.
Low‑temperature shrinkage – ASTM D2732 / ISO 11501 / GB/T 12027 – We measure the shrinkage (the permanent reduction in length) of polymer films, tapes, and tubing after conditioning at the specified low temperature. The test assesses the dimensional stability of the material under cold exposure.
Warpage and distortion measurement – for large‑area and multi‑material assemblies – We measure the flatness and the out‑of‑plane distortion of large panels and assemblies after conditioning at the specified low temperature, using a laser profilometer or a coordinate measuring machine (CMM).

Environmental and Durability Testing – Simulating Real‑World Cold‑Climate Conditions

Thermal cycling and thermal shock – IEC 60068‑2‑14 / GB/T 2423.22 – We subject the test article to a defined number of temperature cycles (typically 50‑200 cycles) between low and high temperatures (e.g., -40 °C to +85 °C) to simulate the thermal stresses experienced during diurnal and seasonal temperature variations. After the cycling, we perform a functional and mechanical check to detect any cracking, delamination, or loosening.
Combined temperature‑humidity cycling – for assessing the effect of condensation and frost – We cycle the temperature and humidity simultaneously (e.g., from -20 °C / 95 % RH to +20 °C / 50 % RH) to simulate the condensation and frost formation that can occur during temperature transitions. The test assesses the resistance of the material to moisture ingress and to frost‑induced damage.
Freeze‑thaw cycling – for concrete, stone, and porous materials – ASTM C1262 / GB/T 50082 – We subject concrete and masonry specimens to repeated freeze‑thaw cycles (e.g., -20 °C to +20 °C, in water) for up to 100 cycles, and measure the weight loss and the compressive strength retention. The test is used to assess the frost resistance of construction materials.
Low‑temperature salt spray and corrosion testing – ASTM B117 / ISO 9227 / GB/T 10125 – We combine low‑temperature conditioning with salt spray exposure (5 % NaCl, 35 °C) to simulate the severe corrosion conditions experienced by components in cold‑climate, coastal, and de‑icing salt environments.

Regulatory Compliance and Product Certification – Supporting Cold‑Climate Market Access

Our low‑temperature endurance testing services are performed in accordance with the most widely used international and national standards. The most commonly requested include:

IEC 60068‑2‑1 – Environmental testing – Part 2‑1: Tests – Test A: Cold – the international standard for cold testing of electrical and electronic equipment
GB/T 2423.1 – Environmental testing – Part 2: Test methods – Test A: Cold – the Chinese national standard for cold testing
ISO 6722 – Road vehicles – 60 V and 600 V single‑core cables – Test methods – for low‑temperature testing of automotive cables
ASTM D746 – Standard Test Method for Brittleness Temperature of Plastics and Elastomers by Impact – for brittleness temperature of plastics
ISO 812 – Rubber, vulcanised – Determination of low‑temperature brittleness – for brittleness temperature of rubbers
ASTM D1329 – Standard Test Method for Evaluating Rubber Property – Retraction at Lower Temperatures (TR Test) – for low‑temperature retraction of rubbers
ASTM E208 – Standard Test Method for Conducting Drop‑Weight Tear Tests on Steel – for evaluating the fracture toughness of steel at low temperatures
ISO 148‑1 – Metallic materials – Charpy pendulum impact test – Part 1: Test method – for Charpy impact testing at low temperatures

Report Acceptance and Regulatory Recognition

All low‑temperature endurance tests are conducted under our ISO/IEC 17025 accreditation, using calibrated environmental chambers, universal testing machines, and instrumentation, all traceable to national and international reference standards. Our final test reports include: a complete description of the test article (material, dimensions, manufacturer), the test method and conditions (temperature, test duration, loading rate), the measured parameters (tensile strength retention, elongation retention, impact strength, compression set, electrical resistance, dimensional change), a statistical summary (mean, standard deviation, coefficient of variation), and a clear pass/fail verdict against your specified acceptance criteria. These reports are accepted by the National Medical Products Administration (NMPA), the State Administration for Market Regulation (SAMR), the Ministry of Industry and Information Technology (MIIT), and international certification bodies for product registration, type approval, and quality assurance. Bilingual (English/Chinese) versions are available to facilitate submissions to domestic and international authorities and to support your global market access.