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GB/T 2423.5-2019 PDF in English

GB/T 2423.5-2019 (GB/T2423.5-2019, GBT 2423.5-2019, GBT2423.5-2019)
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GB/T 2423.5-2019: PDF in English (GBT 2423.5-2019)

GB/T 2423.5-2019
Environmental testing--Part 2. Test methods--Test Ea and guidance. Shock
ICS 19.040
National Standards of People's Republic of China
Replaces GB/T 2423.5-1995, GB/T 2423.6-1995
Environmental tests. Part 2. Test methods
Test Ea and guidelines. Impact
(IEC 60068-2-27..2008, Environmental testing-Part 2-27. Tests-
TestEaandguidance. Shock, IDT)
Published on May 10,.2019
2019-12-01 Implementation
State Administration of Market Supervision
Published by China National Standardization Administration
Foreword I
1 range 1
2 Normative references 1
3 Terms and definitions 2
4 Test equipment description 2
4.1 Feature Requirements 2
4.2 Measurement system 5
4.3 Installation 6
5 Severity 6
6 Pretreatment 7
7 Initial inspection and function test 7
8 Test 7
9 Recovery 8
10 Final inspection 8
11 Information to be given in the relevant regulations 8
12 Information to be given in the test report 8
Appendix A (Normative Appendix) Waveform Selection and Application Guidelines10
Appendix B (Informative) Other characteristics of the impulse response spectrum and pulse waveform 16
Appendix C (Informative) Comparison of Impact Tests 21
References 22
GB/T 2423 "Environmental Test Part 2" is divided into several parts according to the test method.
This part is Part 5 of GB/T 2423.
This section is drafted in accordance with the rules given in GB/T 1.1-2009.
This section replaces GB/T 2423.5-1995 "Environmental Tests for Electrical and Electronic Products Part 2. Test Methods Test Ea and Guidelines. Impact
Strike "and GB/T 2423.6-1995" Environmental Tests for Electrical and Electronic Products Part 2. Test Methods Test Eb and Guidelines. Collisions ". Headquarters
The content of GB/T 2423.5-1995 and GB/T 2423.6-1995 is integrated. With GB/T 2423.5-1995, GB/T 2423.6-
Compared with.1995, the main technical changes are as follows.
--- Added the requirement of cut-off frequency when using low-pass filter in 4.2 measurement system;
--- In Chapter 5, the requirement for the number of impacts in each direction has been added;
--- The table in Figure 4 combines the original Figure 4 of GB/T 2423.5-1995 and the table of Figure 2 of GB/T 2423.6-1995;
--- The severity level of Table 1 has increased.
This section uses the translation method equivalent to IEC 60068-2-27..2008 "Environmental Tests Part 2-27. Test Test Ea and Guide
Then. Shock.
The Chinese documents that have a consistent correspondence with the international documents referenced normatively in this section are as follows.
--- GB/T 2421.1-2008 Environmental Test Part 1. Overview and Guidelines (IEC 60068-1. 1988, IDT);
--- GB/T 2423.39-2018 Environmental test Part 2. Test method Test Ee and Guide. Bulk cargo test includes
Bounce (IEC 60068-2-55..2013, IDT);
--- GB/T 4798.1-2005 Environmental conditions for the application of electric and electronic products Part 1 Storage (IEC 60721-3-1..1997,
--- GB/T 4798.5-2007 Environmental conditions for the application of electric and electronic products Part 5. Ground vehicle use (IEC 60721-3-
5..1997, MOD).
The following editorial changes have been made in this section.
--- Modified the standard name.
This section is proposed and managed by the National Technical Committee for Environmental Conditions and Environmental Testing of Electrical and Electronic Products (SAC/TC8).
This section was drafted. the Fifth Institute of Electronics of the Ministry of Industry and Information Technology, Guangzhou Intelligent Equipment Research Institute Co., Ltd., Shanghai Quality Supervision
Supervision and Inspection Technology Research Institute, Wuhu Saibao Information Industry Technology Research Institute Co., Ltd.
The main drafters of this section. Cheng Debin, Lu Zhaoming, Xie He, Hou Weiguo.
This section replaces GB/T 2423.5-1995 and GB/T 2423.6-1995.
The previous releases of GB/T 2423.5-1995 are.
--- GB/T 2423.5-1981.
The previous releases of GB/T 2423.6-1995 are.
--- GB/T 2423.6-1981;
--- GB/T 2424.4-1981.
Environmental tests. Part 2. Test methods
Test Ea and guidelines. Impact
1 Scope
This part of GB/T 2423 provides standard procedures for determining the ability of a sample to withstand non-repetitive or repetitive impacts of specified severity.
The purpose of this test is to expose the cumulative damage and degradation caused by mechanical weaknesses and/or performance degradation and impact, and to facilitate
Use these materials in conjunction with relevant specifications to determine whether the sample is acceptable. In some cases, this impact test can also be used to determine
Product structural integrity, or as a means of quality control (see A.2).
This test is mainly for samples without packaging and samples whose packaging can be considered as part of the product under transport conditions. if not
Carry out the test with the packaged item and assign it to the test sample. However, if the item is packaged, treat the product and its packaging as one
Test sample. GB/T 2423.43-2008 introduces the acceptance test of packaging products.
This section is written for pulse waveforms, Appendix A gives guidelines for selecting and using these pulse waveforms, and Appendix B discusses
Characteristics of various waveforms.
If possible, the severity of the test and the shock pulse waveform applied to the sample mimic as much as possible the actual transport or
The effect of the working environment; the purpose of the test is to evaluate the structural integrity and compliance with the design requirements (see A.2 and A.4).
During the test, the sample is always fixed to the impact tester table directly or through a fixture.
Note. This section uses the term "shock testing machine" and does not exclude other methods of generating pulse waveforms.
Where applicable, one of the responsibilities of the Technical Committee is to use basic safety publications in the preparation of publications.
2 Normative references
The following documents are essential for the application of this document. For dated references, only the dated version applies to this article
Pieces. For undated references, the latest version (including all amendments) applies to this document.
GB/T 2423.43-2008 Environmental test for electric and electronic products Part 2. Test methods Vibration, shock and similar dynamics
Installation of test samples (IEC 60068-2-47..2005, IDT)
IEC 60068-1 Environmental Testing Part 1. Overview and Guidelines (Environmental testing-Part 1. General and
IEC 60068-2-55 Environmental Tests Part 2-55. Test Ee and Guidelines. Bounce (Environmentaltesting-Part 2-
55. Tests-TestEeandguidance. Bounce)
IEC 60721-3-1 Environmental Classification Conditions Part 3. Environmental Classification Parameters and Their Harshness Section 1. Storage
(Classificationofenvironmentalconditions-Part 3. Classificationofgroupsofenvironmentalparame-
tersandtheirseverities-Section1. Storage)
IEC 60721-3-5 Environmental Classification Conditions Part 3. Environmental Classification Parameters and Their Severity Section 5. Ground Vehicle Use
(Classificationofenvironmentalconditions-Part 3. Classificationofgroupsofenvironmentalparame-
tersandtheirseverities-Section5. Groundvehicleinstalations)
Guide104 Preparation of safety publications, basic safety publications, and series of safety publications (Thepreparationofsafety
3 terms and definitions
The following terms and definitions apply to this document.
Note. Most of the terms used are defined in ISO 2041 [1] 1) or IEC 60068-1. The following additional terms and definitions also apply to this section.
1) Numbers in square brackets refer to references.
One of the fixed points, and in any case rigidly connected to the fixed point.
Note 1. The test requirements are guaranteed by several checkpoints.
Note 2. If there are more than 4 fixed points, the relevant specifications should specify 4 representative fixed points for inspection.
Note 3. In special cases, such as for large or complex samples, if the inspection point is not required to be close to the fixed point, it is specified in the relevant specifications.
Note 4. When a large number of small samples are installed on a fixture, or when a small sample has many fixed points, a single checkpoint (i.e., reference point) can be selected.
Export control signals. This signal reflects the characteristics of the fixture, not the sample's fixed point. This is only the lowest total
It is only feasible when the vibration frequency is much higher than the upper limit of the test frequency.
The part where the sample is connected to the fixture or impact test bench is usually the place where the sample is fixed.
Note. If the actual installation structure of the sample is used as a fixture, the fixing point is on the installation structure and not on the sample.
The standard acceleration produced by the gravity of the earth varies with altitude and geographic latitude.
Note. For ease of use, this section rounds the gn value to an integer value of 10m/s2.
Repetition rate
Number of impacts per second.
Shock severity level shockseverity
The severity level of the impact test includes peak acceleration, nominal pulse duration, and number of impacts.
Velocity change
Absolute value of sudden change in speed due to application of prescribed acceleration.
Note. If the speed change occurs in a time shorter than the basic period of the excitation pulse involved, it is usually considered a sudden change.
4 Test equipment description
4.1 Feature requirements
When the specimen is mounted on the impact test bench with or without a clamp, the impact pulse applied at the inspection point shall be similar to Figures 1 and 2
And one of the acceleration vs. time curves shown by the dashed lines in FIG.
4.1.1 Basic pulse waveform
This section includes three types of waveforms. half-sine wave, post-peak sawtooth wave and trapezoidal wave. The choice of waveform depends on several factors, this section
The priority order of waveform selection is given (see A.3).
The prescribed basic pulse waveform is as follows (see A.3).
--- Half sine wave. half cycle of sine wave, as shown in Figure 1;
--- Back peak sawtooth wave. asymmetric triangle with short fall time, as shown in Figure 2;
--- Trapezoidal wave. Symmetrical trapezoid with short rise and fall times, as shown in Figure 3.
The actual pulse should be within the tolerance indicated by the solid line in the relevant figure.
Note. When it is not possible to obtain pulse waveforms that fall within the specified tolerance range, the relevant specifications should specify another method that can be used (see A.5).
Figure 1.Waveform and tolerance range of a half sine wave
Explanation (applies to Figures 1 to 3).
. Nominal pulse line;
. Tolerance range line;
D. the duration of the nominal pulse;
A. The peak acceleration of the nominal pulse;
T1. The shortest time for pulse monitoring when an impact is generated with a traditional impact test bench;
T2. The shortest time for pulse monitoring when an impact is generated with an electric vibration test bench.
Figure 2 Waveform and tolerance range of the post-peak sawtooth wave
Figure 3 Waveform and tolerance range of trapezoidal wave
4.1.2 Repetition rate
The repetition rate should ensure that the relative motion inside the sample between the two impacts is basically zero, and the acceleration value at the checkpoint should be as shown in Figure 1.
Within the tolerances shown (see A.7).
Note. For the evaluation formula of repetition rate, see A.7.
4.1.3 Tolerance of speed change
For all pulse waveforms, the actual speed change should be within ± 15% of its corresponding nominal pulse value.
When the speed change is determined by the integration of the actual pulse, it should be integrated from 0.4D before the pulse to 0.1D after the pulse, where D is the nominal
The duration of the pulse.
Note. If the speed variation tolerance cannot be obtained due to the lack of an accurate integration device, the relevant specifications should specify another method that can be used (see A.5
And A.6).
4.1.4 Lateral motion
When the method of 4.2 is used, the positive or negative peak acceleration perpendicular to the predetermined impact direction at the check point should not exceed the predetermined square.
Up to 30% of the nominal peak pulse acceleration.
Note. If the error requirements of the lateral movement are not met, the relevant specifications should specify another method that can be used (see A.5).
4.2 Measurement system
The characteristics of the measurement system shall ensure that the tolerances required for the actual pulses in the predetermined direction of the checkpoint are measured in Figures 1, 2 and 3.
Within range. The requirements of Figure 4 apply to the frequency response of a control signal measurement system without a low-pass filter. When a low-pass filter is used, the filter
The cut-off frequency fg (-3dB point) of the wave filter characteristics is not lower than.
fg =
fg --- the cut-off frequency of the low-pass filter, the unit is kilohertz (kHz);
D --- pulse duration, unit is millisecond (ms).
Can have an important impact on measurement accuracy.The frequency response of the entire measurement system including the accelerometer should be within the tolerance of Figure 4.
Within (see A.5).
Note. The duration of the impact is equal to or less than 0.5 ms.It is not necessary to have such high frequencies as f3 and f4 in Figure 4.Therefore, relevant specifications should specify
Substitute value.
Pulse duration
Low cut-off frequency
High cut-off frequency
Frequency at which the response may rise by 1dB
f1 f2 f3 f4
0.2, 0.3 20 120 20 40
0.5 10 50 15 30
2,3 2 10 5 10
11 0.5 2 1 2
16,18,30 0.2 1 1 2
Figure 4 Frequency characteristics of the measurement system
4.3 Installation
The sample shall be installed on the table of the impact tester or mounted on the table by a clamp according to IEC 60068-2-47.
5 Severity
Relevant specifications should give both pulse waveform and shock severity levels. The relevant specifications should specify that the shock applies to all three axes.
Positive and negative directions. The effect of gravity should be considered when focusing on the attitude of the test. Unless the actual conditions of use are known or otherwise specified,
Use one of the waveforms given in 4.1.1 and the corresponding severity levels in Table 1. Bold is the preferred combination. The corresponding speed change is also in Table 1.
Given in.
The number of impacts in each direction can be selected from the following values.
3 ± 0
100 ± 5
500 ± 5
1000 ± 10
5000 ± 10
Note. If the severity level here cannot simulate the impact of the known environment on the sample, the relevant specifications can use the standard pulse shown in Figure 1, Figure 2 and Figure 3.
One of the waveforms (see A.4) specifies other suitable test severity levels.
Table 1 Severity level of impact test
Peak acceleration
Pulse duration
Half sine
Δν =
πAD × 10
Back peak jagged
Δν = 0.5AD × 10-3
Δν = 0.9AD × 10-3
m/s2 gn ms m/sm/sm/s
50 5 6 0.2a 0.2 0.3
50 5 30 1 0.8 1.4
60 6 11 0.4 0.3 0.6 b
100 10 16 1 0.8 1.4
100 10 11 0.7 0.6 1 c
100 10 6 0.4 0.3 0.5
150 15 6 0.6 0.5 0.8 c
150 15 11 1.1 0.8 1.5
200 20 11 1.4 1.1 2 b
250 25 6 1 0.8 1.4 c
300 30 6 1.1 0.9 1.6
300 30 18 3.4 2.7 4.9
400 40 6 1.5 1.2 2.2 c
400 40 11 2.8 2.2 4
500 50 3 1 0.8 1.4
500 50 11 3.5 2.8 5
Table 1 (continued)
Peak acceleration
Pulse duration
Half sine
Δν =
πAD × 10
Back peak jagged
Δν = 0.5AD × 10-3
Δν = 0.9AD × 10-3
m/s2 gn ms m/sm/sm/s
800 80 6 3.1 2.4 4.3 c
1000 100 2 1.3 1 1.8 c
1000 100 6 3.8 3 5.4
1000 100 11 7 5.5 9.9
2000.200 3 3.8 3 5.4
2000.200 6 7.6 6 10.8
5000 500 1 3.2 2.5 4.5
10000 1000 1 6.4 5 9
15000 1500 0.5 4.8 3.8 6.8
30000 3000 0.2 3.8 3 5.4
30000 3000 0.3 5.7 4.5 8.1
50000 5000 0.3 9.5 7.5 13.5 d
100000 10000 0.2 12.7 10 18 d
a Bold pulse waveforms are preferred.
b RTCADO160E/F recommends. "Functional impact" 6gn, 3 times in each direction; "Crash impact" 20gn, 1 time in each direction.
c Preferred for repeated impacts.
d These shocks may not be fully realized in accordance with the strict requirements of this section.
6 Pretreatment
Relevant specifications can put forward pre-processing requirements.
7 Initial inspection and function test
The appearance, size and function of the sample shall be tested in accordance with the relevant specifications.
8 Test
Shocks shall be applied in each of the three orthogonal axes of the sample a number of times specified in the relevant specification. When multiple identical samples are tested, the
In order to arrange the samples properly, impact in three axes simultaneously (see A.7).
When installing or transporting, the attitude of the sample is known.Since the impact is most sensitive in a certain direction of an axis, the relevant specifications should stipulate that
Number of impacts on this axis, direction and attitude. Otherwise, the test should be performed in both directions of the three axes. For example, usually the largest shock plus
The speed is along the vertical direction. When the attitude during transportation is known, the impact should be in the direction of the vertical axis. When the attitude is unknown, the relevant specifications should stipulate
Number of impacts per axis (see A.7).
Relevant specifications should specify whether the sample works during the test and whether the function is monitored.
9 Recovery
It is sometimes necessary to provide a period of time after the test and before the final test to bring the sample to the same conditions as the initial test, such as temperature.
Relevant specifications should stipulate the conditions for restoration.
10 Final inspection
The samples shall be inspected for appearance, size, function, and other requirements specified in the relevant specifications.
Relevant specifications should give criteria for sample acceptance or rejection.
11 Information to be given in the relevant specifications
When the relevant specification adopts this test, as long as it is applicable, the writer of the specification should provide the following information. Pay special attention to the asterisk (*) mark
Project because this information is required.
Article number
a) Pulse waveform * 4.1.1, A.3
b) Tolerance 4.1.1, A.5
c) Speed change 4.1.3, A.6
d) Lateral motion 4.1.4
e) Excitation axis, test attitude and test axis * Chapter 8
f) Installation method * 4.3
g) Severity rating * Chapter 5, A.4
h) Impact direction and number of impacts * Chapter 5, Chapter 8
i) Preprocessing Chapter 6
j) Chapter 7 of Initial Inspection and Functional Inspection
k) Chapter 7 of Functional Testing
l) Work Mode and Function Monitoring Chapter 8
m) Recover Chapter 9
n) Criteria for acceptance and rejection * Chapter 10
o) Final Inspection Chapter 10
12 Information to be given in the test report
The test report should give at least the following information.
a) the customer (name and address);
b) laboratory (name and address);
c) test report (issue date, unique identification number);
d) test date;
e) test purpose (development test, verification test, etc.);
f) test standard, version (procedures related to the test);
g) sample description (unique identification number, picture, photo, quantity, evaluation of the first inspection of the sample, etc.);
h) installation of samples (fixture characteristics, pictures, photos, excitation axes);
i) excitation axis (test attitude and excitation axis);
j) the performance of the test equipment (transverse motion, etc.);
k) measurement system, sensor location (description, picture, photo, etc.);
l) measurement system uncertainty (calibration data, last date and next date);
m) initial, intermediate or final measurements;
n) demanding severity levels (from test specifications);
o) Test severity and documentation (from checkpoints);
p) Test conclusions (evaluation of sample conditions);
q) test situation records;
r) test summary;
s) the person in charge of the test (name and signature);
t) Send (Report Distribution List).
Note. Test logs should be written in the test records, for example, a chronological list of test runs with test parameters, observations and actions taken during the test,
And measured data sheets. Test logs can be attached to test reports.
Appendix A
(Normative appendix)
Waveform Selection and Application Guidelines
A.1 Introduction
This section provides a test method that reproduces how the sample was affected during transport or use. This test is not a reproduction of reality
In order to enable different people to obtain consistent test results in different laboratories, the parameters specified in this test are
Over-standardized with appropriate tolerances. Standardization of values can also enable components to withstand some of the test rigors specified in this section.
Cool level ability to classify.
A.2 Application scope of the test
Many samples are susceptible to shock during use, storage, handling, and transportation. The magnitude of these shocks varies widely and is complex
The impact test provides a simple method for determining the non-repetitive and repetitive impact of a sample. This test is to mount the sample on
The test is performed on the fixture or impact test bench. If the sample is repeatedly impacted in bulk when installed or transported, it should
Test in accordance with IEC 60068-2-55 (see Appendix C).
Impact tests are also applicable to structural integrity tests performed on component samples for identification and/or quality management. In these cases
In general, high-acceleration impacts are usually used.The main purpose is to apply a known impact to the internal structure of the sample (especially the cavity sample).
Strike force (see Chapter 1).
To ensure the integrity of all test information, the author of the specification should refer to Chapter 11 of this section.
A.3 Pulse waveform (see Chapter 1)
According to the purpose of the test, three commonly used "classic" shock pulse waveforms can be used (see 4.1.1 and Table 1).
Semi-sinusoidal pulses are suitable for simulating the impact of a linear system's impact or the deceleration of a linear system, such as the elastic structure.
Back peak sawtooth pulses have a more uniform response spectrum than half-sine pulses and back peak saw pulses.
Trapezoidal pulses can produce a higher response over a wider frequency spectrum than half-sine pulses. If the purpose of the experiment is to simulate
This kind of shock waveform can be used for the impact of the impact environment caused by the explosion bolt of the space detector or satellite launch section.
Note. The most commonly used are half-sine pulses, trapezoidal pulses are basically not used for component samples.
See Appendix B for information on the shock response spectrum associated with these pulses.
When the impact response spectrum of the working or transport environment is known, Figure A.1, Figure A.2 and Figure A.3 should be referred to in order to choose the closest to this impact
Pulse waveform of the response spectrum. When the impact response spectrum of the work or transport environment is unknown, Tables A.1 and A.2 should be consulted because they list
Test severity grades and pulse waveforms for samples of all types of transportation and various modes of work.
For packed samples, the characteristics of shocks during loading and unloading and transportation are usually simple, so you can use
A half-sinusoidal waveform pulse obtained by checking the speed variation.
I = initial response spectrum;
R = residual response spectrum.
Figure A.1 Impact response spectrum of a symmetric half-sine pulse
I = initial response spectrum;
R = residual response spectrum.
Figure A.2 Shock response spectrum of a back-to-peak sawtooth pulse
I = initial response spectrum;
R = residual response spectrum.
Figure A.3 Shock response spectrum of a symmetrical trapezoidal pulse
A.4 Test severity level
The test severity levels and pulse waveforms applied to the sample shall be as close as possible to the conditions during which the sample will be transported, stored, handled, or used.
To withstand the environment, if the purpose of the test is to evaluate the integrity of the structure, it should withstand the environment required by the design.
For the same sample, perform a non-repeatable impact test (three impacts in each axis and in each direction).
The ability to withstand the greatest stresses in the life cycle is a common and appropriate way.
Similarly, repeated stress tests with lower stress can determine the ability of the sample to withstand repeated impacts, or determine material fatigue during use due to material fatigue.
Law results.
The transportation environment is usually harsher than the use environment. In this case, the selection of the test severity level needs to be consistent with the transportation environment. Of course
However, although the samples only need to withstand the environmental conditions of transportation, they are usually required to operate in working environmental conditions. So, if possible, samples are usually
Can perform impact tests under the above two conditions, that is, parameter measurement after impact test in transportation environment conditions and test in working environment conditions
Perform an impact test of the functional inspection during the inspection.
Consideration should be given to giving sufficient safety margin between the severity of the test and the actual environmental conditions.
When the actual working or transportation environment is unknown, the appropriate test severity level should be selected from Table 1.
It should be emphasized that the impact test is based on experience and basic sufficient tests to give credible measurements and does not simulate the real environment.
In determining the test severity level, the writer of the specification should consider the relevant content in the series of environmental conditions standards, for example, IEC 60721,
That is, IEC 60721-3-1 and IEC 60721-3-5, but it should be kept in mind that the values listed in these standards are the actual impacts.
Can provide standard impact pulses for testing consistent with impact effects during life.
Table A.1 Typical examples of pulse waveforms and test severity levels for various applications
Severity rating
Acceleration waveform duration
m/s2 gn ms
Waveform device type
Half sine
Back peak jagged
Basic tests on the structure of loading and unloading.
Permanently installed on the ground
Road, rail or air transportation
Equipment in impact packaging
Half sine
Back peak jagged
Structural strength of the installation. On ordinary roads or
Cargo transportation in railroad cars or aircraft
All-position installation
Half sine
Back peak jagged
Trapezoid a
Wheeled vehicles (standard
Road or rail), subsonic or supersonic
Transport aircraft, merchant ships, light naval vessels
Transported components.
Installed on wheeled vehicles (standard road or iron
Road), subsonic or supersonic transport aircraft, commercial
Equipment for transportation in ships, light naval vessels
Components in or above the means of transport
Used components.
Components installed in heavy industry equipment
Installed and transported in a safe location for off-road vehicles
Bulk in standard road or rail vehicles
Equipment for long distance transportation. Suitable in industrial areas
Use, and will be subject to
Equipment, such as dock cranes, forklift trucks, etc.
Impact product
Half sine
Back peak jagged
Trapezoid a
Transported by off-road vehicle in reliable packaging
Element in equipment transported by off-road vehicle
Pieces or yuan used on off-road vehicles
Produced in bulk on road or rail vehicles
Components in equipment being transported
Withstands severe loading in road or rail transportation
Due to the ignition, the separation of multi-stage rockets (in the air
Carrier), aerodynamic shock, space carrier
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.