Environmental stress screening method considering aging failure mechanism of mechanical product
By employing an environmental stress screening method to address the aging failure mechanisms of mechanical products, initial testing, simulated stress application, temperature and humidity adjustment, and testing are conducted. This approach solves the problem of the complexity of mechanical product failure mechanisms and improves product reliability and quality.
Patent Information
- Application Number
- CN202511410718.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-29
- Publication Date
- 2026-01-13
AI Technical Summary
The lack of existing environmental stress screening standards for mechanical products leads to diverse and complex failure mechanisms, making it difficult to effectively eliminate early failures and affecting product reliability.
An environmental stress screening method is adopted, including initial performance testing, simulated continuous stress application, temperature and humidity adjustment, high and low temperature cycling, aging performance testing and disassembly inspection, to screen for aging failure mechanisms of mechanical products.
Screening methods can effectively eliminate early failures in mechanical products, improve product reliability, reduce failure rates, and enhance product quality during the manufacturing process.
Smart Images
Figure CN121323944A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of mechanical product reliability technology, and in particular to an environmental stress screening method that takes into account the aging failure mechanism of mechanical products. Background Technology
[0002] For routine environmental stress screening, relevant domestic and international standards are applicable to electronic products. Electrical, optoelectronic, electromechanical, and electrochemical products can refer to relevant standards. Currently, there are no applicable standards or guidelines for environmental stress screening of mechanical products. Mechanical products, typically composed of several mechanical parts, are complex systems designed to perform a specific function, resulting in diverse and interconnected failure mechanisms. Common failure mechanisms for mechanical products mainly include fatigue, aging, and wear.
[0003] Considering the diversity and complexity of failure mechanisms in mechanical products, taking mechanical products with aging as the main failure mechanism as an example, an environmental stress screening method is proposed. This method can be used in the research and development and production stages of mechanical products to eliminate early failures and improve product reliability. Summary of the Invention
[0004] The present invention aims to solve the technical problems in the prior art by providing an environmental stress screening method that takes into account the aging failure mechanism of mechanical products.
[0005] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:
[0006] An environmental stress screening method considering the aging failure mechanism of mechanical products includes the following steps:
[0007] Step 1: Conduct initial performance testing on the mechanical product under standard atmospheric conditions to obtain pre-test data;
[0008] Step 2: Simulate the continuous stress applied to the mechanical product under working conditions, adjust the temperature inside the test chamber to raise the room temperature to the first temperature setting value, and maintain the first temperature setting value for a set time;
[0009] Step 3: Adjust the humidity inside the test chamber to the first humidity setting value, maintain the first humidity setting value for a set time, and adjust the humidity inside the test chamber to reduce the first humidity setting value to the second humidity setting value. At this time, adjust the temperature inside the test chamber to the first temperature setting value.
[0010] Step 4: Reduce the first temperature setting to the second temperature setting and hold the second temperature setting for the set time;
[0011] Step 5: Increase the second temperature setting to the first temperature setting and hold the first temperature setting for the set time;
[0012] Step 6: repeat the cycle of step 4 and step 5;
[0013] Step 7: reduce the first temperature setting value to room temperature, remove the continuous stress applied to the mechanical product in the working state, and then detect the aging performance of the mechanical product, obtain the post-test data, and compare the pre-test and post-test data.
[0014] As a further description of the application, the performance detection of the mechanical product in step 1 and step 7 includes: respectively detecting the performance of the plastic parts, rubber parts and insulation parts in the mechanical product.
[0015] As a further description of the application, for the mechanical product containing electric control or insulation parts, the power-on test is simultaneously performed in step 1, step 5 and step 7, and the power-off test is simultaneously performed in step 2, step 3 and step 4.
[0016] As a further description of the application, for the mechanical product with disassembly conditions, after completing steps 1-7, disassembly inspection is performed.
[0017] As a further description of the application, in step 2 and step 5, the first temperature setting value maintaining time is: not less than 48h.
[0018] As a further description of the application, in step 3, the first humidity setting value maintaining time is: not less than 48h and not more than 120h.
[0019] As a further description of the application, in step 2, step 4, step 5 and step 7, the temperature change rate is not more than 5℃ / min.
[0020] As a further description of the application, in step 6, the number of repeated cycles is generally not less than 10.
[0021] Compared with the prior art, the technical effects of the application are as follows:
[0022] The application fully considers the failure mechanism of the mechanical product with aging as the main failure mechanism, the environmental stress type leading to product failure, and formulates a reasonable and accurate method for removing early failures of the same type of products, excluding defects / failures of the same type of products caused by process or material in the manufacturing production stage, reducing the failure rate of the product, and improving the reliability of the product. BRIEF DESCRIPTION OF DRAWINGS
[0023] Fig. 1 is a flowchart of the application;
[0024] Fig. 2 is a curve graph of the application. DETAILED DESCRIPTION
[0025] The present invention will now be described in detail with reference to the accompanying drawings.
[0026] like Figs. 1-2 As shown, an environmental stress screening method considering the aging failure mechanism of mechanical products includes the following steps:
[0027] Step 1: Conduct initial performance testing on the mechanical product under standard atmospheric conditions to obtain pre-test data;
[0028] Step 2: Simulate the application of continuous stress to the mechanical product under working conditions, adjust the temperature inside the test chamber to raise the room temperature to the first temperature setting value, and maintain the first temperature setting value for a set time; preferably, the application of continuous stress can be achieved by applying a load to the mechanical product or by applying a force to the mechanical product to cause deformation;
[0029] Step 3: Adjust the humidity inside the test chamber to the first humidity setting value, maintain the first humidity setting value for a set time, and adjust the humidity inside the test chamber to reduce the first humidity setting value to the second humidity setting value. At this time, adjust the temperature inside the test chamber to the first temperature setting value. Preferably, the first humidity setting value can be 95%RH (relative humidity), and the second humidity setting value can be ≤30%RH.
[0030] Step 4: Reduce the first temperature setting to the second temperature setting and hold the second temperature setting for the set time;
[0031] Step 5: Increase the second temperature setting to the first temperature setting and hold the first temperature setting for the set time;
[0032] Step 6: Repeat steps 4 and 5 in a loop;
[0033] Step 7: Lower the first temperature setting to room temperature, remove the continuous stress that was applied to the mechanical product under working conditions, and then conduct an aging performance test on the mechanical product to obtain the test data and compare the data before and after the test.
[0034] The high and low temperature settings mentioned above are determined according to the relevant technical specifications of the mechanical product. Generally, they are taken as the product's operating limit temperature or exceeding the product's operating limit temperature, or the temperature resistance limit of the most sensitive material in the product (such as a certain rubber, plastic, or grease), but cannot exceed the product's design limit temperature. Simultaneously, they should be strictly lower than the maximum short-term tolerance temperature allowed for the sensitive material. When determining the second temperature setting for temperature cycling, the material's embrittlement temperature should be fully considered. The temperature cycling hold time can be referenced in GJB1032 or Appendix GJB1032A (mainly for environmental stress screening of electronic products).
[0035] The performance detection of the mechanical product in step 1 and step 7 includes: the performance detection of the plastic parts, rubber parts and insulation parts in the mechanical product respectively. The performance detection items of the plastic parts include color difference, tensile / bending strength, oxidation degree, etc.; the performance detection items of the rubber parts include hardness, crack propagation, etc.; and the performance detection items of the insulation parts include dielectric constant, surface resistivity, volume resistivity, volume breakdown strength, etc.
[0036] For the mechanical product containing electric control or insulation parts, the power-on test is simultaneously performed in step 1, step 5 and step 7, and the power-off test is simultaneously performed in step 2, step 3 and step 4. The power-on and power-off test is to simulate the actual working condition of the mechanical product and apply the corresponding excitation to the mechanical product. The steps of turning on and off the power are selected according to the principle of exciting the product failure or exposing the product defects as soon as possible.
[0037] For the mechanical product with disassembly conditions, after completing steps 1-7, disassembly inspection is performed. The disassembly inspection can focus on the materials and parts sensitive to aging.
[0038] The above screening method mainly goes through the initial performance detection stage → high temperature storage aging stage → humid heat aging stage → high and low temperature cycle stage → aging performance detection stage. The method fully considers the failure mechanism of the mechanical product with aging as the main failure mechanism, the environmental stress type leading to product failure, and formulates a reasonable and accurate method for removing early failures of the same type of products, excluding defects / failures of the same type of products caused by process or materials in the manufacturing and production stage, reducing the failure rate of the product and improving the reliability of the product.
[0039] In step 2 and step 5, the first temperature setting value maintaining time is not less than 48h.
[0040] In step 3, the first humidity setting value maintaining time is not less than 48h and not more than 120h.
[0041] In step 2, step 4, step 5 and step 7, the temperature change rate is not more than 5℃ / min. The temperature change rate can adopt the average value of the whole temperature change process.
[0042] In step 6, the repeated cycle number is generally not less than 10 times. The repeated cycle number can be tailored according to the product and material characteristics.
[0043] Obviously, the above examples are only examples for clearly illustrating, but not limitation to the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, all the embodiments are not required to be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.
Claims
1. A method of environmental stress screening taking into account the aging failure mechanism of a mechanical product, characterized in that, The method comprises the following steps: Step 1: initial performance detection of the mechanical product under standard atmospheric conditions, and obtaining pre-test data; Step 2: simulating the continuous stress applied to the mechanical product in the working state, adjusting the temperature in the test chamber, increasing the room temperature to a first temperature setting value, and maintaining the first temperature setting value for a set time; Step 3: adjusting the humidity in the test chamber to a first humidity setting value, maintaining the first humidity setting value for a set time, adjusting the humidity in the test chamber, and reducing the first humidity setting value to a second humidity setting value, at this time, the temperature in the test chamber is adjusted to the first temperature setting value; Step 4: reducing the first temperature setting value to a second temperature setting value, and maintaining the second temperature setting value for a set time; Step 5: increasing the second temperature setting value to the first temperature setting value again, and maintaining the first temperature setting value for a set time; Step 6: repeating steps 4 and 5; Step 7: reducing the first temperature setting value to room temperature, removing the simulated continuous stress applied to the mechanical product in the working state, and performing aging performance detection on the mechanical product, obtaining post-test data, and comparing the pre-test and post-test data.
2. The environmental stress screening method that considers the aging failure mechanism of a mechanical product according to claim 1, characterized by, The performance detection of the mechanical product in steps 1 and 7 comprises: respectively detecting the performance of plastic parts, rubber parts and insulation parts in the mechanical product.
3. The environmental stress screening method that considers the aging failure mechanism of a mechanical product according to claim 1, characterized by, For mechanical products containing electric control or insulation parts, power-on testing is performed simultaneously in steps 1, 5 and 7, and power-off testing is performed simultaneously in steps 2, 3 and 4.
4. The environmental stress screening method that considers the aging failure mechanism of a mechanical product according to claim 3, characterized by, For mechanical products with disassembly conditions, after completing steps 1-7, disassembly inspection is performed.
5. The environmental stress screening method of claim 4, wherein the step of determining the failure mechanism of the mechanical product is performed by a method comprising: determining a failure mechanism of the mechanical product based on the failure data and the operational data. In steps 2 and 5, the first temperature setting value maintaining time is: not less than 48h.
6. The environmental stress screening method of claim 5, wherein the step of determining the failure mechanism of the mechanical product is performed by a method comprising: determining a failure mechanism of the mechanical product based on the failure data and the operational data. In step 3, the first humidity setting value maintaining time is: not less than 48h, and not more than 120h.
7. The environmental stress screening method that considers the aging failure mechanism of a mechanical product according to claim 6, wherein In steps 2, 4, 5 and 7, the temperature change rate is not more than 5℃ / min.
8. The environmental stress screening method of claim 7, wherein the step of determining the failure mechanism of the mechanical product is performed by a method comprising: determining a failure mechanism of the mechanical product based on the failure data and the operational data. In step 6, the number of repeated cycles is generally not less than 10.