PDF GB/T 43354-2023 English
Search result: GB/T 43354-2023
| Standard ID | Contents [version] | USD | STEP2 | [PDF] delivered in | Name of Chinese Standard | Status |
| GB/T 43354-2023 | English | 165 |
Add to Cart
|
0-9 seconds. Auto-delivery.
|
Methods for plane bending fatigue of copper alloy elastic strip
| Valid |
PDF Preview: GB/T 43354-2023
GB/T 43354-2023: PDF in English (GBT 43354-2023) GB/T 43354-2023
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 77.040.10
CCS H 22
Methods for plane bending fatigue of copper alloy elastic
strip
ISSUED ON: NOVEMBER 27, 20023
IMPLEMENTED ON: JUNE 01, 2024
Issued by: State Administration for Market Regulation;
Standardization Administration of the People's Republic of China.
Table of Contents
Foreword ... 3
1 Scope ... 4
2 Normative references ... 4
3 Terms and definitions ... 4
4 Method principle ... 4
5 Test conditions ... 5
6 Testing machine ... 5
7 Specimens ... 6
8 Test steps ... 7
9 Result presentation ... 9
10 Test report ... 10
Foreword
This document was drafted in accordance with the rules given in GB/T 1.1-2020
"Directives for standardization - Part 1: Rules for the structure and drafting of
standardizing documents".
Attention is drawn to the possibility that some of the elements of this document may be
the subject of patent rights. The issuing authority shall not be held responsible for
identifying any or all such patent rights.
This document was proposed by China Nonferrous Metals Industry Association.
This document shall be under the jurisdiction of National Technical Committee on Non-
ferrous Metals of Standardization Administration of China (SAC/TC 243).
The drafting organizations of this document: Northwest Rare Metal Materials Research
Institute Ningxia Co., Ltd., China Nonferrous Metal (Ningxia) Oriental Group Co., Ltd.,
Ningbo Xingye Shengtai Group Co., Ltd., China Aluminum Luoyang Copper
Processing Co., Ltd., China Copper Central China Copper Co., Ltd., Qingyuan
Chujiang High-Precision Copper Strip Co., Ltd., and Tongling Nonferrous Metals
Group Co., Ltd. Jinwei Copper Branch.
Main drafters of this document: Jiao Xiaoliang, Li Meisui, Cao Hucheng, Liu Feng, Ma
Xiao, Wang Shaojun, Wang Dongxin, Han Jungang, Cui Shuhui, Zheng Yun, Lou
Dongge, Dong Zhenxing, Fang Dexiang, Hu Tongsheng, Zhang Xinhui, Zhao Xiaowei,
Wang Peng, Zhang Jiankang, Xu Chunwei, Zhao Jian, Xie Guanfu, Wang Zhiping, Yi
Waigeng.
Methods for plane bending fatigue of copper alloy elastic
strip
1 Scope
This document describes the principle, test conditions, testing machine, specimens, test
procedures, result expression and test report of the plane bending fatigue test method
for copper alloy elastic strip.
This document is applicable to the determination of plane bending fatigue properties of
copper alloy elastic strips with a thickness of 0.1 mm~1.0 mm at 10℃~35℃.
2 Normative references
The following referenced documents are indispensable for the application of this
document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
GB/T 16825.1, Verification of static uniaxial testing machines -- Part 1:
Tension/compression testing machines -- Verification and calibration of the force-
measuring system
3 Terms and definitions
There are no terms or definitions that require definition in this document.
4 Method principle
The prepared specimen is mounted on a fixed cantilever constant deflection fatigue
testing machine (hereinafter referred to as the "testing machine"). A load is applied to
it. The specimen is bent repeatedly at a certain frequency until the specimen fails or
reaches a specified number of cycles. The principle diagram is shown in Figure 1.
h - Thickness of the specimen at the load-bearing point, in millimeters (mm).
The calculation result is rounded to two decimal places.
8.1.2 Uniform cross-sectional specimens
The maximum bending stress S of the uniform cross-section specimen is calculated
according to formula (2):
Where,
P - Applied load, in Newton (N);
L - Distance from the force application point to the force receiving point, in millimeters
(mm);
b - Width of the specimen at the force receiving point, in millimeters (mm);
h - Thickness of the specimen at the force receiving point, in millimeters (mm).
The calculation result is rounded to two decimal places.
8.2 Static calibration of loads
If the testing machine is equipped with a load sensor, the load (P) can be recorded
directly. No static calibration is required. If such a device is not available, static
calibration of the load can be performed according to the following steps: Paste a strain
gauge on the axis of the center position of the specimen working area. Perform static
calibration step by step. The calibration method is as follows: Paste a strain gauge on
the specimen working area and connect it to the strain indicator. Fix one end of the
specimen. Then add weights step by step vertically at the force application point as the
load (P). After the data stabilizes, record the strain value shown by the strain indicator
until the stress on the specimen is equal to or slightly greater than the required test stress.
Reinstall the specimen in the same clamping position. Measure 2 ~3 times.
8.3 Specimen installation
When installing the specimen, the alignment check shall be completed first. The center
line of the fixture shall coincide with the force axis of the testing machine, so that the
specimen and the upper and lower fixtures of the testing machine remain coaxial.
Ensure that the force is evenly distributed over the entire cross section of the specimen.
Try to reduce the stress other than the specified bending stress on the specimen. The
clamping force of the specimen shall be as small as possible to reduce the probability
of the specimen breaking in the jaws. Use an adjustable torque wrench to fix the
specimen on the fixture (the recommended torque value is 3 N·m).
8.4 Test frequency
The test frequency is generally in the range of 5 Hz~200 Hz. The recommended test
frequency is 5 Hz~100 Hz. The tests of the same batch of specimens shall be carried
out at the same frequency. The stress cycle frequency shall not cause overheating of the
specimens or resonance of the testing machine. At high frequencies, the specimens will
generate a lot of heat, which will affect the test results of fatigue life and fatigue strength.
If the specimens are hot, it is recommended to reduce the test frequency. If the specimen
temperature exceeds 35℃, it shall be noted in the report.
8.5 Application of loads
8.5.1 The load shall be applied smoothly and accurately. Overloading is not allowed.
8.5.2 If the testing machine is equipped with a load sensing device, the load can be
adjusted to the required value through the control system. If the testing machine is not
equipped with a load sensing device, the load can be adjusted to the required value
through the load adjustment device.
8.6 Determination of S-N curve
Usually at least 5 stress levels are taken. The number of specimens at each stress level
shall be gradually increased as the stress level decreases. The conditional fatigue limit
obtained by the lifting and lowering method is used as the lowest stress level point on
the S-N curve. The number of specimens at each stress level is not less than 3. If
necessary, it shall be determined by negotiation between the two parties. With stress S
as the ordinate and fatigue life N as the abscissa, the S-N curve is drawn using the best
fitting method.
8.7 Termination of tests
The test is terminated when the specimen fails or reaches the specified number of cycles.
If other conditions cause the test to be interrupted during the test, the number of cycles
and the rest time at the time of interruption must be noted in the test report.
9 Result presentation
9.1 By tables
The table shall include specimen identification, test sequence, test shape and size, test
frequency, test stress, fatigue life or number of cycles at the end of the test, and failure
criteria.
9.2 By charts
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
|