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How to Choose a Temperature and Humidity Chamber Meeting -70℃ for Composite Materials Testing

Jan 28 2026

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The “Environmental Memory” of Composite Materials

Composite materials are highly sensitive to temperature and humidity. Before conducting mechanical tests such as tensile, compression, or bending, environmental conditioning is crucial to ensure reliable and reproducible results. Minor variations in temperature or humidity can significantly impact material performance, particularly in high-end applications like aerospace and deep-sea exploration.

The Significance of -70℃

For aerospace, deep-sea, and extreme environment applications, -70℃ is not just a low temperature—it represents a realistic simulation of harsh operating conditions. Only a temperature and humidity chamber capable of reliably reaching -70℃ can accurately evaluate the low-temperature performance of composite materials.

Common Challenges

Conventional chambers often struggle under extreme low temperatures, resulting in:

Large temperature drift affecting test accuracy
Failure of humidity control due to frosting
Slow cooling rates, extending test cycles

A high-quality temperature and humidity chamber can overcome these limitations. LIB industry’s ultra-low temperature humidity chambers provide a stable, precise, and reproducible testing environment, ensuring reliable composite materials testing results.

Key Selection Criteria for a Temperature and Humidity Chamber

1. Cooling System — The Heart of the Temperature Humidity Chamber

Achieving ultra-low temperatures relies on cascade refrigeration technology. Compared with single-stage compressors, cascade systems can:

Stably reach -70℃
Achieve rapid cooling rates
Use environmentally friendly refrigerants

LIB industry cascade refrigeration systems ensure rapid, stable cooling from room temperature to -70℃, guaranteeing the accuracy and efficiency of composite materials mechanical testing.

2. Humidity Control at Extreme Low Temperatures

Low temperatures make humidity control challenging, as moisture tends to freeze. Selection criteria include:

Anti-frost design
Fast-response dehumidification
Precision chamber sealing and heat-stress-resistant materials

LIB industry temperature and humidity chambers feature multi-layer vacuum insulated observation windows and high-density polyurethane insulation, maintaining stable humidity even at -70℃.

3. Uniformity and Fluctuation — Ensuring Reliable Test Data

Referenced Standards: ASTM D5229, GB/T 2573
Forced air circulation design ensures uniform temperature and humidity across the chamber

LIB industry chambers are optimized for airflow distribution, achieving ±0.5℃ temperature uniformity to ensure consistent test results for all composite material samples.


Model	TH-100	TH-225	TH-500	TH-1000
Interior Volume	100L	225L	500L	1000L
Heat load	1000W
Temperature Range	A : -20℃ ～ +150 ℃ B : -40℃ ～ +150 ℃ C: -70℃ ～ +150 ℃
Temperature Fluctuation	± 0.5 ℃
Temperature Deviation	± 2.0 ℃
Humidity Range	20% ~ 98% RH
Humidity Deviation	± 2.5% RH
Cooling Rate	1 ℃ / min
Heating Rate	3 ℃ / min
Controller	Programmable color LCD touch screen controller,PC Link, LAN interface for remote control
Cooling system	Mechanical compression refrigeration system
Refrigerant	Environmentally friendly refrigerant,compliant with the GWP standards requirements
Water supply system	Automatic water supply; Water purification system
Interior Material	SUS304 stainless steel

Special Requirements for Composite Materials Testing

High-Precision Sensors

Using PT100 high-precision sensors ensures accurate temperature and humidity measurements.

Data Recording and Traceability

Supports USB data export and remote control, meeting laboratory accreditation requirements and ensuring full traceability of experimental data.

Sample Rack Design

Optimized internal layout allows efficient placement of multiple composite material specimens while maintaining airflow uniformity.

LIB industry offers customizable sample racks to maximize space utilization and test efficiency for batch composite testing.

Composite Materials Testing Process and Standards

Typical Testing Process

Sample Preparation: Cut composite material specimens to standard dimensions according to ASTM or GB/T guidelines and label each sample.
Environmental Conditioning: Place samples in the temperature and humidity chamber at the target temperature (e.g., -70℃) and humidity, allowing the material to reach equilibrium.
Mechanical Testing: Conduct tensile, compression, or bending tests under stable conditions to ensure reliable data.
Data Recording and Analysis: Use built-in sensors or external devices to monitor temperature and humidity, generating a complete traceable data chain.

Referenced Standards

ASTM D5229 / D5529M: Moisture absorption and mechanical performance testing for composite materials
GB/T 2573: Environmental testing methods for composite materials
ISO 9142 / ISO 14126: Conditioning and environmental performance testing

LIB industry chambers support full environmental simulation and data recording, ensuring compliance with international and domestic testing standards for research and quality certification purposes.

Laboratory Deployment Recommendations

Power Requirements

Ultra-low temperature chambers consume high power; confirm laboratory electrical capacity in advance.

Space for Heat Dissipation

Cascade refrigeration systems generate significant heat; provide adequate maintenance and ventilation space.

After-Sales Support and Technical Services

Extreme low-temperature equipment is complex; evaluate manufacturer maintenance and support capabilities.

Choosing LIB industry temperature and humidity chambers ensures:

3-year warranty
Lifelong technical support
24/7 English-speaking service
Globally stocked spare parts
Professional commissioning and installation

Guaranteeing safe, efficient, and continuous operation for every composite materials test.

Frequently Asked Questions About Temperature and Humidity Test Chamber

What language options are available for the Temperature and Humidity Test Chamber controller? Will it increase the cost?

To support global users, LIB industry temperature and humidity test chamber controllers are supplied with English and Chinese interfaces as standard, ready for immediate use at no extra cost.

Optional languages such as French, German, Russian, and Polish are available upon request, helping users operate the chamber smoothly in different regions.

Can curves be drawn during the Temperature and Humidity Test Chamber test process?

Yes. Real-time curve display is a standard feature of LIB industry temperature and humidity test chambers.

Temperature and humidity curves are generated and displayed during the test process, allowing users to clearly monitor environmental changes. Data is automatically recorded once per minute, with continuous storage supported for up to three years, ensuring stable, complete, and traceable test data.

If a custom test port or viewing window is required, will there be delivery delays?

For standard test ports or regular viewing window adjustments, there is no impact on delivery time compared to standard temperature and humidity test chamber models.

For special custom designs, production is arranged according to technical requirements to ensure timely delivery.
If an optical glass viewing window is required, the delivery time is typically extended by 5–10 days, with close coordination to minimize waiting time.

What is the maximum fast temperature change rate? Can it reach 20 °C/min?

The standard temperature change rate of LIB industry temperature and humidity test chambers is 5–10 °C/min.

For advanced applications, customized solutions can achieve 20 °C/min or higher, fully supporting non-standard requirements for accelerated and high-demand environmental testing.

Conclusion and Call to Action

If your laboratory is planning -70℃ environmental simulation for composite materials testing, contact LIB industry technical experts to receive a customized selection report, ensuring every mechanical test is efficient, accurate, and safe.

References