Sulfur corrosion test method
The sulfur corrosion test method simulates sulfur dispersion and contact with silver in electronic components to determine corrosion, addressing the inability of existing methods to assess sulfur-induced corrosion.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- TOYOTA JIDOSHA KK
- Filing Date
- 2023-11-08
- Publication Date
- 2026-07-22
AI Technical Summary
Existing methods cannot determine the presence or absence of corrosion of electronic components due to sublimated sulfur using particle simulation.
A sulfur corrosion test method using computer-based simulation that simulates the dispersion of sublimated sulfur in a CAD space, detects contact with silver in electronic components, and derives corrosion results based on detection.
Enables determination of corrosion occurrence due to sublimated sulfur adherence to silver in electronic components through simulation, eliminating the need for component analysis by SEM-EDX.
Smart Images
Figure 0007893218000001 
Figure 0007893218000002 
Figure 0007893218000003
Abstract
Description
Technical Field
[0004] ,
[0006] , , , , , ,
[0005] , , ,
[0003] , , , , ,
[0001] This disclosure relates to a method for sulfur corrosion testing of electronic components using the particle method.
Background Art
[0002] Patent Document 1 discloses a technique for performing simulation of a gas by the particle method. This Patent Document 1 describes a method of arranging a plurality of particles in an analysis region and simulating the behavior of a particle system composed of the plurality of particles using the molecular dynamics method.
Prior Art Documents
Patent Documents
[0003]
Patent Document 1
Summary of the Invention
Problems to be Solved by the Invention
[0004] > In the technique described in Patent Document 1, although it is possible to simulate the dispersion of sublimated sulfur using the particle method, it is not possible to derive the presence or absence of corrosion of electronic components by sublimated sulfur.
[0005] This disclosure has been made in view of the above problems, and an object thereof is to provide a sulfur corrosion test method capable of deriving the presence or absence of corrosion of electronic components by sublimated sulfur through simulation.
Means for Solving the Problems
[0007] According to the sulfur corrosion test method described above, it is possible to determine by simulation whether or not corrosion occurs due to sublimated sulfur adhering to the silver of electronic components. [Brief explanation of the drawing]
[0008] [Figure 1] Flowchart showing the processing procedure for a sulfur corrosion test method according to one embodiment of this disclosure. [Figure 2] Image of the test layer (space in CAD) where the simulation will be performed. [Figure 3] A conceptual diagram showing the dispersion of sulfur within the test layer used for the simulation. [Figure 4] An illustrative diagram illustrating an example of a method for determining corrosion locations. [Figure 5] A diagram showing the concentration distribution for each element. [Modes for carrying out the invention]
[0009] The sulfur corrosion test method disclosed herein reads the elemental composition from CAD data of an electronic component loaded into simulation software, converting the electronic component into an aggregate of elements. This enables the simulation software to simulate the corrosion of electronic components by sulfur. The embodiments of this disclosure will be described in detail below with reference to the drawings.
[0010] <Embodiment> [control] Figure 1 is a flowchart illustrating the processing procedure of a sulfur corrosion test method according to one embodiment of the present disclosure. The sulfur corrosion test method shown in Figure 1 is performed by a computer (such as an ECU) mounted on the vehicle.
[0011] (Step S110) In the simulation, the computer loads CAD data of sulfur (sulfur powder) and CAD data of the electronic components (such as ECUs) to be subjected to corrosion testing into the simulation software. The computer also reads the physical properties from the physical property information of the loaded CAD data.
[0012] Once the computer reads the CAD data for sulfur and electronic components, and the physical properties are read from the physical property information in the CAD data, the process proceeds to step S120.
[0013] (Step S120) Based on the physical properties it reads, the computer calculates a specific portion of the electronic component containing silver as an aggregate of particles using the particle method (converting the electronic component into an aggregate of particles). This specific portion contains elements other than silver. The computer then places these calculated particles of silver and other elements into a CAD-like space.
[0014] Figure 2 shows an image of the test layer 30 (space in CAD) where the simulation will be performed. As shown in Figure 2, sulfur (sulfur powder) 10 and electronic components 20 are placed inside the test layer 30, and the electronic components 20 are represented as particles of multiple elements arranged together, as shown in the enlarged cross-sectional view. Typically, the computer automatically calculates and arranges the particles of each element (Ag, Ti, etc.) using material properties read from the material property information of the CAD data.
[0015] When particles of each element are arranged inside the test layer by a computer, the process proceeds to step S130.
[0016] (Step S130) The computer performs an analysis by simulation using the test layer. In this analysis, a simulation is performed in which sulfur is sublimated by the particle method and the sublimated sulfur particles are dispersed in the test layer.
[0017] FIG. 3 is a diagram showing an image when sulfur 10 is dispersed inside the test layer 30. As shown in FIG. 3, in the test layer 30, it can be seen that the particles (S) of sublimated and dispersed sulfur 10 spread inside the test layer 30 and reach the electronic component 20 and adhere to the surface.
[0018] When the analysis by simulation is performed by the computer, the process proceeds to step S140.
[0019] (Step S140) The computer determines the corrosion location of the electronic component by sulfur. This determination is made by detecting the portion where the sublimated sulfur particles (S) contact the silver particles (Ag) contained in the electronic component. When this sulfur and silver contact, silver sulfide (Ag2S) that becomes rust is generated.
[0020] FIG. 4 is an image diagram for explaining an example of the method for determining the corrosion location. As illustrated in FIG. 4, the portion where the particles (S) of sulfur 10 contact the silver particles (Ag) of the electronic component 20 is determined to have corrosion. In order to improve the accuracy of this determination, it is desirable to perform this for each of the silver particles (Ag). On the other hand, for the portion where the particles (S) of sulfur 10 contact the particles (such as Ti) of elements other than silver in the electronic component 20, it is determined that there is no corrosion. That is, the locations of the particles (such as Ti) of elements other than silver are determined to have no corrosion regardless of the presence or absence of contact with the particles (S) of sulfur 10.
[0021] Furthermore, in determining the location of corrosion, it may be possible to detect the number of times sulfur particles (S) come into contact with silver particles (Ag) of the electronic component based on the sulfur concentration (number of particles). The more contacts detected between these particles, the greater the degree of corrosion of the silver by sulfur at that contact point.
[0022] Once the computer determines the areas of corrosion on the electronic components caused by sulfur, the process proceeds to step S150.
[0023] (Step S150) The computer displays the concentration distribution of each element or molecule used in the analysis simulation on a designated screen. Since this concentration distribution represents the component distribution, component analysis using energy-dispersive X-ray spectroscopy (SEM-EDX) becomes unnecessary.
[0024] Figure 5 shows the concentration distribution for each element or molecule. In the example in Figure 5, the concentration distributions of sulfur (S), silver (Ag), titanium (Ti), and epoxy (Epoxy) are shown.
[0025] The process ends when the concentration distribution is displayed on the screen by the computer.
[0026] <Effects and Actions> As described above, the sulfur corrosion test method according to one embodiment of the present disclosure simulates the dispersion of sulfur sublimated by the particle method in a CAD space containing electronic components, detects contact between the sublimated sulfur and the silver of the electronic components (which has been converted into particles based on the physical properties of the electronic components), and determines whether or not the electronic components are corroded by sulfur based on this detection result. This process makes it possible to simulate corrosion caused by sulfur adhering to silver using simulation software, which was not possible in the past. [Industrial applicability]
[0027] This disclosure can be used, for example, when you want to simulate the corrosion of electronic components by sulfur. [Explanation of Symbols]
[0028] 10 Sulfur 20 Electronic Components 30 test layers
Claims
1. A sulfur corrosion test method using computer-based simulations of sulfur corrosion on electronic components, An acquisition step to acquire physical property information of the aforementioned electronic component, Based on the physical property information obtained in the acquisition step, the electronic component containing silver is calculated as an aggregate of multiple particles by the particle method, and the electronic component is placed in a CAD space, and the dispersion step simulates the dispersion of sublimated sulfur by the particle method in the CAD space having the electronic component. A detection step for each of the silver particles contained in the electronic component, for which it is detected that the sulfur sublimated in the dispersion step has come into contact with the silver, Based on the detection results in the above detection step, a derivation step is performed to derive the corrosion result of the area where the sulfur and the silver came into contact, A sulfur corrosion test method comprising: a display step of displaying a cross-sectional view of the electronic component showing the concentration distribution of sulfur and silver as a result of the corrosion on a predetermined screen.
2. In the detection step, the number of times the sulfur sublimated in the dispersion step came into contact with the silver contained in the electronic component is detected based on the concentration of the sulfur. The sulfur corrosion test method according to claim 1, wherein the derivation step derives a result that the greater the number of times the contact was detected in the detection step, the greater the degree of sulfur corrosion at the contacted location.
3. In the detection step, it is detected that the sulfur sublimated in the dispersion step has come into contact with the silver particles. The sulfur corrosion test method according to claim 1, wherein in the derivation step, for each silver particle, the result is derived that there is corrosion in the areas of the silver particle that came into contact with the sulfur particle in the detection step, and the result is derived that there is no corrosion in the areas of the silver particle that did not come into contact with the sulfur particle in the detection step.
4. The aforementioned specific portion of the electronic component contains particles of elements other than silver, The sulfur corrosion test method according to claim 3, wherein the derivation step derives the result that there is no corrosion at the location of the elemental particles, regardless of the contact between the sulfur particles and the elemental particles in the detection step.