Temperature cycling vs. thermal shock testing?

Temperature Shock Test:

Heating up The cooling rate is not less than 30 minutes. The temperature varies widely, and the severity of the test increases with the rate of temperature change.

The difference between the temperature shock test and the temperature cycle test is mainly due to the different stress load mechanisms. The temperature shock test mainly investigates the failure caused by creep and fatigue damage, while the temperature cycling mainly investigates the failure caused by shear fatigue.

Two-tank test device is allowed for temperature shock testing; The temperature cycle test is carried out using a single-tank test setup. In a two-tank chamber, the temperature change rate is greater than 50 minutes.

Causes of temperature shock: Severe temperature changes in manufacturing and repair processes such as reflow soldering, drying, reprocessing, and repair.

Accelerated stress test: Accelerated test is an accelerated test performed on a test sample in a shorter time than in a real-world environment to investigate its failure mechanism. The acceleration of the test is to use the method of increasing stress to make the test sample fail in a short period of time.

However, care must be taken to avoid failure mechanisms caused by other stress causes.

Temperature Cycling Test:

Temperature cycling is the exposure of the test sample to a set test environment with alternating high and low temperatures. In order to avoid the effects of temperature shock, the rate of temperature change during the test must be less than 20 minutes. At the same time, in order to achieve the effect of creep and fatigue damage, it is recommended that the test temperature cycle is 25 100, or the cycle test of 0 100 can also be used according to the use of the product, and the exposure time is 1 5 minutes each.

First, the use is different.

The effects of temperature cycling are as follows:

1.It can accurately simulate complex natural environments such as low temperature, high temperature, high temperature and high humidity, low temperature and low humidity, and is suitable for product reliability testing in various industries such as plastics, electronics, food, clothing, vehicles, metals, chemicals, building materials, etc.

2.This machine provides a high temperature and high humidity environment to compare the material changes and the degree of attenuation of strength before and after rubber and plastic tests; This machine can also simulate the container environment, in order to detect the discoloration and shrinkage of rubber and plastic at high temperature and high humidity, and this machine is specially designed to test the heat resistance, cold resistance and moisture resistance of various materials.

The uses of the thermal shock test chamber are as follows.

It is mainly used for battery safety performance testing, furnace thermal test, heating test, etc.

2. There is no humidity in the thermal shock test chamber.

Difference Between Temperature Cycling and Thermal Shock Test:

1. The temperature conversion rate is different. The temperature conversion speed of the thermal shock test is very fast, and the temperature is a sudden change process, such as the temperature conversion time of the two-box basket type thermal shock test chamber of Hongzhan Technology is 10s, while the general temperature cycle test does not pursue the sudden change of temperature conversion, and the temperature rise and fall speed is about 1 3 min.

2. There is no humidity test for the cold and thermal shock test, and the humidity test can be selected for the temperature cycle test.

3. The difference between the thermal shock test and the temperature cycle test is mainly due to the different stress load mechanism. The thermal shock test mainly investigates the failure caused by creep and fatigue damage, while the temperature cycling mainly investigates the failure caused by shear fatigue.

4. The two-tank test device is allowed for the thermal shock test, and the single-tank test device is required for the temperature cycle test.

1. The time of shelving at room temperature is different, that is: the temperature cycle is generally that after the object is taken out at a cold or hot temperature, the object should be restored to room temperature at room temperature, and the next hot or cold ambient temperature will be entered after more than half an hour; The cold coarse thermal shock immediately enters the next temperature environment;

2. The biggest difference between cold and heat (temperature cycle} and temperature shock is the difference in the temperature change rate, which leads to the difference in the performance of thermal expansion and cold contraction of substances in the case of different temperature change rates.

The inside of the thermal shock box is divided into two areas, one part is high temperature and one part is low temperature, and the conversion between high and low temperature is generally carried out within 15 seconds. At the same time, this is not humidity control.

The indicators of constant temperature and humidity chamber are mainly temperature and humidity, and the temperature change rate of different boxes is not the same, and the temperature change is a period of time during this test. The temperature and humidity curve of the box can be used to determine the test limit that the box can do. The thermal shock time is fast, 80 degrees to minus 20 degrees Celsius in 3 seconds, and the temperature cycle is different, slowly changing from one temperature to another, and the temperature change time is long.

Hello, Temperature Shock and Temperature Cycling are 2 different test items:

The temperature shock test has a temperature rise and cooling rate of no less than 30 minutes, and the temperature change range is large, and the severity of the test also increases with the increase of the temperature change rate.

Temperature cycling is to expose the test sample to a set test environment with alternating high and low temperatures, and the temperature change rate must be less than 20 minutes during the test.

If you need to do these two tests, you can send me a private message.

Both the high and low refrigeration cycles use the reverse Karo cycle, which consists of two isothermal processes and two adiabatic processes. The process is as follows: the refrigerant is adiabatic and compressed to a higher pressure by the compressor, and the work is consumed to increase the exhaust temperature, and then the refrigerant is athermally exchanged with the surrounding medium through the condenser to transfer heat to the surrounding medium.

After the refrigerant expands through the valve adiabatic expansion to do work, then the refrigerant temperature decreases. Finally, the refrigerant is athermally absorbed from the hotter object through the evaporator, reducing the temperature of the cooled object. This cycle repeats itself to achieve the purpose of cooling.

Impact in different temperature sections: the multi-stage evaporator structure is cut off accordingly, the evaporation area is controlled to match the refrigeration capacity expansion valve, and the output of the refrigeration system is used to reasonably reduce the output of the heater to achieve constant energy saving; There is also a separate ventilation valve that brings in ambient air during exhaust (normal temperature recovery).

The air inlet draws in outside air when the ambient temperature is exposed.

The exhaust port discharges hot gas from the mechanical room and the test area.

The test start time is pre-set, and the test chamber automatically starts and is ready to start the test.

Exposure time reduction function.

The downwind temperature of the test area reaches the exposure temperature and then switches to the next exposure.

Pre-processing Post-processing function.

Before or after the start of the cyclic test, the specimen is exposed to high temperatures (heat treatment) for a certain period of time.

Dry running function.

A certain amount of time is in operation under the test finish.