What is the Thermal Shock Test and the Application?

Thermal shock test, also known as temperature shock test or thermal shock test, is used to assess the adaptability of products to the rapid change of ambient temperature, is an indispensable test in the identification test of equipment design and routine test in the batch production stage, and in some cases can also be used for environmental stress screening test. It can be said that the frequency of application of cold and thermal shock test chambers in verifying and improving the environmental adaptability of equipment is second only to vibration and high and low temperature tests.

Thermal Shock Test Chamber is a necessary test equipment for metal, plastic, rubber, electronics and other material industries, used to test material structure or composite materials, in an instant through extremely high temperature and extremely low temperature continuous environment to endure the degree, in the shortest time to detect the test sample due to thermal expansion and contraction caused by chemical changes or physical damage.

The Purpose of Thermal Shock Test

In fact, as a tool, the purpose of the Thermal Shock Test chamber is different when used in different stages of product development:

1.The engineering development stage can be used to find product design and process defects;

2.Provide a basis for product finalization or design appraisal and acceptance decisions in the batch production stage;

3.When applied as environmental stress screening, the purpose is to eliminate early failures of the product.

Among the many environmental test equipment, Thermal Shock Test Chamber, high and low temperature alternating humidity and heat test chamber occupy an important position, and its use range covers all walks of life. They can do both high temperature tests and low temperature tests, and can also convert from high temperature to low temperature or from low temperature to high temperature, but the conversion time is too long and the rate is too slow to meet the performance test of the sample under the condition of sudden temperature change. As a result, a Thermal Shock Test Chamber was born, which can quickly make the test sample experience temperature change to test its withstand temperature shock and observe its performance change. Thermal Shock Test Chamber is usually divided into two parts: high temperature area and low temperature zone because the temperature change rate requires extremely fast. In order to make the test sample can drop from high temperature to extremely low temperature in an instant, a mobile channel is designed between the high temperature area and the low temperature area, such as moving the hanging basket, the test sample can be moved from the high temperature area to the low temperature area within a few seconds, and the thermal expansion and contraction caused by the hot and cold shock of the experimental article and the related physical and chemical reactions are tested.

Thermal Shock Test Chamber adopts the form of integral combination structure, usually high temperature studio is located at the upper end, low temperature studio is located at the lower end, the test sample can be transmitted between the two, and through the reasonable combination of each system to form a special heat insulation structure, and has the effect of heat storage and cold storage. Thermal Shock Test Chambers are widely used in aerospace, national defense industry, automotive electronics, chemical materials and other fields due to their efficient temperature change to test the physical and chemical evolution and damage of experimental articles in the rapid evolution of high and low temperatures, so as to further improve the quality.

LIB Thermal Shock Test Chamber

The Thermal Shock Test Chamber is divided into three-chamber type and two-chamber type according to the test requirements and test standards. The difference lies in the test method and internal structure. The three-zone type is divided into a cold storage room, a heat storage room and a test room, and the product is placed in the test room during testing. The two-zone type is divided into a high-temperature room and a low-temperature room. The high and low temperature switching is realized through the movement of the basket driven by the motor. The product is placed in the basket and moves with the basket.

Model	TS-500
Inner dimensions of test room	650*650*500mm
Volume of test room	211L
Load of test room	50kg
Upper limit preheat temperature	+220℃
Heating time	Ambient temperature to ~ + 200℃, within in 30 minutes.
Lower limit pre-cool temperature	-75℃
Cooling time	Ambient temperature to ~ -70℃, within in 30 minutes

Test Process

Generally speaking, the operation of the Thermal Shock Test Chamber is divided into five steps: pretreatment, initial inspection, test, recovery, and final inspection. The following LIB will share with you the detailed process content:

1. Pretreatment: Place the tested sample under normal test atmospheric conditions until the temperature is stable.

2. Initial inspection: compare the tested sample with the standard requirements, and put it directly into the Thermal Shock Test Chamber after meeting the requirements.

3. Test:

1) The test sample should be placed in the test chamber according to the standard requirements, and the temperature in the test chamber should be raised to the specified point, and kept for a certain period of time until the test sample reaches a stable temperature.

2) After the high-temperature stage is over, transfer the test sample to a low-temperature test chamber (chamber) adjusted to -55°C within 5 minutes, and keep it for 1 hour or until the test sample reaches a stable temperature.

3) After the low-temperature stage is over, transfer the test sample to a high-temperature test chamber (chamber) adjusted to 70°C within 5 minutes, and keep it for 1 hour or until the test sample reaches a stable temperature.

4) Repeat the above experimental method to complete three cycles. Depending on the size of the sample and the size of the space, the time may have a slight error.

4. Recovery: After the test sample is taken out of the test chamber, it should be recovered under normal test atmospheric conditions until the test sample reaches a stable temperature.

5. Final inspection: evaluate the inspection results against the degree of damage in the standard and other methods.

Features of LIB Thermal Shock Series Chambers

LIB 2-zone hot cold thermal shock test chamber is available in small capacity and large capacity to meet different testing requirements. Test can be performed during thermal shock testing from -70 to +220℃.

The specimen is transferred from cold chamber to hot chamber by basket automatically. The basket slides vertically and smoothly through rails, to make the specimen expose to the two workroom. TS series thermal shock chamber has two independently controlled hot and cold zones, the specimen automatic transferred between different temperature zones. Users can easily observe the product as it’s transferred between different temperature zones through built-in viewing windows.

LIB 3TS series thermal shock test chamber is just one zone for workroom. It circulates cold and hot air through the pneumatic damper on the left and right sides. This design makes external size smaller, and the 3TS series thermal shock chambers can be pre-heated and pre-cooled to achieve faster temperature change.

Maintenance of Thermal Shock Test Chamber

1. The radiator (condenser) of the refrigerating unit of the thermal shock testing machine should be maintained regularly and kept clean. Dust and sticky condenser will cause the high-voltage switch of the compressor to trip and cause false alarms. The condenser should be maintained regularly and monthly. Use a vacuum cleaner to suck off the dust attached to the cooling mesh of the condenser or use a hard brush to clean it after starting the machine or use a high-pressure air nozzle to blow off the dust.

2. When opening and closing the door or taking the test object from the test chamber, do not let the object touch the rubber edge on the door to prevent the rubber edge from being damaged and shortening the life.

3. The ground around and at the bottom of the fuselage should be kept clean at all times to avoid accidents and performance degradation caused by a large amount of dust being sucked into the unit.

4. When the cold and heat shock test machine takes the product after the test time is up, it must be turned off and the staff must wear dry, anti-electricity, and temperature-resistant gloves to take and place the product.

5. Cleaning and maintenance of the inside and outside of the cold and heat shock test machine.

6. The internal impurities (objects) should be removed before the operation of the thermal shock testing machine.

7. The power distribution room should be cleaned at least once a year. When cleaning, please use a vacuum cleaner to remove the indoor dust. The outside of the cabinet must be cleaned more than once a year, and it can be wiped with soapy water when cleaning.

Thermal Shock Test Conditions and Standards

ISO 16750-4

ANSI/UL 60950-1

The thermal shock test is a test method for testing materials to withstand extreme temperature changes. High and low temperature impact tests are commonly used to test the reliability and durability of industrial products such as electronic components, automotive parts and aerospace components. According to the requirements of the standard, the high and low temperature impact test should be carried out in a heating circulation chamber or a cooling circulation chamber that meets the requirements of the ambient temperature. For high and low temperature impact tests, appropriate test conditions should be established according to the use environment of different materials and products, such as minimum temperature, maximum temperature, holding time and cooling time, etc. The test requires multiple cycles, and each cycle includes three stages of rapid heating, holding, and rapid cooling. After each stage is complete, the material or product must be observed and inspected to identify any damage or changes in performance. The results of high and low temperature impact testing are not only widely used in industry, but also of recognized importance in standardization bodies such as the International Organization for Standardization (ISO) and the American National Standards Institute (ANSI). For example, the ISO 16750-4 standard specifies the requirements and procedures for high and low temperature impact tests of automotive electrical equipment, while the ANSI/UL 60950-1 standard specifies the requirements for high and low temperature impact tests for safety electrical equipment. Therefore, the high and low temperature impact test has become one of the necessary tests for industrial quality control and product reliability assurance. Not only does it help determine whether a manufacturer complies with industry standards, but it also helps improve product quality and performance. When conducting thermal shock tests, it is necessary to pay attention to safety issues and comply with the regulations of standardization agencies to ensure the accuracy and reliability of test results.

Application

Thermal Shock Test Chambers can be applied to the following industries:

1. National defense industry industry: defense industry generally refers to the military industry.

2. Auto parts industry: auto parts are a product that constitutes the whole unit of the car and serves the car.

3. Plastic industry: Plastic is widely used and is an indispensable component in home appliances, automobiles, mobile phones, PCs, medical equipment, and lighting appliances.In addition to the above industries, it can also be used in communication components, electronic and electrical components, metals, chemical materials, military industry, aerospace, active parts, PCB base wrench, electronic chip IC, and other industries.

LIB can provide you with professional test solutions and quality thermal shock test chambers. Contact us immediately to get your own test chamber so that you can improve the reliability and durability of your products.