A method for predicting the corrosion life of a vehicle

Abstract

The application discloses a kind of prediction methods of vehicle corrosion life, and the prediction method includes: S1, obtains market environment corrosion intensity;S2, establishes whole vehicle road intensification corrosion test system, determines the test method suitable for the test system;S3, using the test system and test method determined, the corrosion intensity of the vehicle to be measured is calculated;S4, in combination with the corrosion intensity of the vehicle calculated and standard corrosion spectrum, the corrosion life of vehicle is predicted.The method can effectively predict the corrosion life of newly developed vehicle, provide strong guarantee for the realization of whole vehicle anticorrosion target, effectively help existing vehicle corrosion problem analysis.

Description

Technical Field

[0001] This invention relates to the field of automotive life prediction technology, and more specifically to a method for predicting the corrosion life of a vehicle. Background Technology

[0002] The losses caused by automotive corrosion have become a social problem. Corrosion not only directly affects the service life and safety of automotive metal parts, but also leads to environmental pollution and traffic accidents, causing losses to social and economic development. According to relevant data reports, the average annual loss from automotive corrosion worldwide is US$1.5-2.5 million, and countries around the world attach great importance to automotive corrosion. Major domestic and foreign automakers carry out corrosion prevention work from the perspectives of defining corrosion prevention targets, corrosion design specifications (structural design, process design, material selection, etc.), corrosion verification (parts, body, whole vehicle), and product quality consistency.

[0003] As a vital means of transportation, automobiles contain a five-figure number of parts and are subject to complex and varied usage conditions. Significant differences exist in climate across regions, and road conditions vary considerably. Temperature, humidity, and air pollution all affect the corrosion of automobiles. The high temperatures generated by the engine, vibrations and impacts during operation, and damage from flying stones all accelerate corrosion. Therefore, predicting the corrosion of an entire vehicle requires consideration of numerous factors and constitutes a complex systems engineering project.

[0004] Currently, there are few studies on automobile life prediction, and most of them focus on service life or fatigue life prediction. Corrosion life prediction is mainly concentrated in the petroleum and power sectors, and is not applicable to the whole vehicle sector. No research on corrosion life of automobiles, especially at the whole vehicle level, has been reported. Summary of the Invention

[0005] To overcome the shortcomings of existing technologies, this invention proposes a method for predicting the corrosion life of vehicles. This method can effectively predict the corrosion life of newly developed vehicle models, providing strong support for achieving overall vehicle corrosion prevention goals. It can also effectively assist in the analysis of corrosion problems in existing vehicle models.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] A method for predicting the corrosion life of a vehicle, the method comprising:

[0008] S1. Obtain the corrosion intensity of the market environment;

[0009] S2. Establish a road-enhanced corrosion testing system for whole vehicles and determine the test methods applicable to this system;

[0010] S3. Using the established testing system and methods, calculate the corrosion intensity of the vehicle under test;

[0011] S4. Based on the calculated vehicle corrosion intensity and standard corrosion spectrum, predict the vehicle corrosion life.

[0012] Preferably, in step S1, the method for obtaining the market environment corrosion intensity is as follows:

[0013] Select typical cities in the target area, measure the intensity of natural environmental corrosion in the target cities, and collect relevant atmospheric environmental data for the corresponding years in the target cities;

[0014] Establish a market environment corrosion intensity measurement model, substitute relevant environmental data of the target year and target city, and calculate the market environment corrosion intensity of the city in that year.

[0015] 9. Further optimized, the process for establishing the market environment corrosion intensity measurement model is as follows:

[0016]

[0017] In formula (1): D i D is the raw data for the atmospheric environment. iUB and D iLB As boundary values, the target interval range for the linear mapping [a1, a2] is set to [0.2, 0.8]. The least squares method is used for fitting, with the goal of minimizing the sum of squared errors, to calculate d. i ;

[0018]

[0019] In equation (2): d i For environment mapping parameters, ω i These are the weighting coefficients for environmental factors;

[0020] R = A·E + B (3)

[0021] In formula (3): R is the annual corrosion equivalent, E is the comprehensive factor of atmospheric environmental corrosivity, and A and B are substitution coefficients.

[0022] Further preferred atmospheric environmental data include temperature, humidity, rainfall, sunshine duration, SO2 concentration, NO2 concentration, and Cl. - concentration.

[0023] Preferably, in step S2, the whole vehicle road enhanced corrosion test system includes environmental accelerated corrosion test on different enhanced road sections and corrosion durability test in an environmental chamber.

[0024] In a further preferred embodiment, in step S2, based on the market environment corrosion intensity, test site conditions, and staff arrangements obtained in step S1, a test method suitable for the whole vehicle road hardening corrosion test system is determined.

[0025] Further preferred experimental methods include:

[0026] After each single cycle, a cycle check is performed. If the target number of cycles is reached, the entire vehicle is disassembled to evaluate the corrosion level of invisible areas. The single cycle steps are: pre-test check → enhanced corrosion road test one → salt spray test one → enhanced corrosion road test two → damp heat alternating cycle test → salt spray test two.

[0027] In a further optimized step S2, the target number of cycles for the whole vehicle road corrosion enhancement test system also needs to be calibrated, and the following formula must be satisfied:

[0028] D=αC (4)

[0029] In equation (4), C is the highest market environmental corrosion intensity obtained in step 1, D is the corrosion intensity required by the whole vehicle road enhanced corrosion test system, and α is the environmental intensity correction coefficient obtained by fitting the market corrosion intensity data with C.

[0030] H = C / D (5)

[0031] In equation (5), H represents the number of annual target cycles.

[0032] Preferably, in step S4, the method for preparing the standard corrosion spectrum includes:

[0033] 1) Prepare standard test plates and standard surface treatment process test plates;

[0034] 2) Environmental corrosion tests were conducted on the standard test plate and the standard surface treatment process test plate respectively;

[0035] 3) Prepare standard corrosion charts based on the test results.

[0036] Preferably, in step S4, different vehicle corrosion life calculation methods can be selected based on different assessment indicators:

[0037] Using the absence of rust on the exterior as the evaluation indicator: Select all visible parts, calculate the corrosion life of each part by referring to the standard corrosion chart, and then calculate the corrosion life of the vehicle.

[0038] Using non-perforation as the evaluation indicator: Select all parts, calculate the corrosion life of each part by referring to the standard corrosion spectrum, and then calculate the corrosion life of the vehicle.

[0039] Using functional non-failure as the evaluation indicator: Select all parts, calculate the corrosion life of each part by referring to the standard corrosion spectrum, and then calculate the corrosion life of the vehicle.

[0040] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0041] 1) The method of the present invention can effectively predict the corrosion life of newly developed vehicle models, provide basic data for vehicle replacement and maintenance, and provide strong support for achieving the overall vehicle corrosion prevention target.

[0042] 2) The method of the present invention accurately predicts the corrosion life of automobiles, reducing or avoiding safety risks caused by corrosion. Detailed Implementation

[0043] This invention provides a method for predicting the corrosion life of a vehicle, the prediction method comprising:

[0044] Step 1: Obtain the market environment corrosion intensity

[0045] The assessment of market environment corrosion intensity mainly involves calculating the market environment corrosion intensity using atmospheric environmental factor data. The specific calculation process includes the following steps:

[0046] ① Atmospheric environmental factor analysis: Based on theoretical analysis and past engineering experience, determine the influence of temperature, humidity, rainfall, sunshine duration, SO2 concentration, NO2 concentration, and Cl. - Concentration is a major factor affecting vehicle corrosion / metal corrosion.

[0047] ② Selection of Characteristic Cities: Select typical cities in the target area, measure the natural environmental corrosion intensity of these cities, and collect relevant atmospheric environmental data for the corresponding years. The selected cities should be representative, encompassing as many climate types as possible, such as South Asian subtropical monsoon climate, tropical monsoon and humid maritime climate, cold temperate semi-arid monsoon climate, and plateau temperate semi-arid monsoon climate. Natural environmental corrosion intensity can be measured through a plate test, where a test plate (generally Q235 low-carbon steel plate) is exposed to natural conditions for one year, and the weight loss / thickness loss is measured to represent the natural corrosion intensity, in μm / year. Atmospheric environmental data should include, but is not limited to, temperature, humidity, rainfall, sunshine duration, SO2 concentration, NO2 concentration, and Cl... - Concentration data.

[0048] ③ Establishment of a natural environment corrosion intensity model: based on temperature, humidity, rainfall, sunshine duration, SO2 concentration, NO2 concentration, Cl... - A mathematical model was established using concentration data and annual corrosion data of the mounting plates. The richer the basic database, the more accurate the model and the more precise the calculation results.

[0049] The process of establishing the market environment corrosion intensity measurement model is as follows:

[0050]

[0051] In formula (1): D i D is the raw data for the atmospheric environment. iUB and DiLB As boundary values, the target interval range for the linear mapping [a1, a2] is set to [0.2, 0.8]. The least squares method is used for fitting, with the goal of minimizing the sum of squared errors, to calculate d. i ;

[0052]

[0053] In equation (2): d i For environment mapping parameters, ω i These are the weighting coefficients for environmental factors;

[0054] R = A·E + B (3)

[0055] In formula (3): R is the annual corrosion equivalent, E is the comprehensive factor of atmospheric environmental corrosivity, and A and B are substitution coefficients.

[0056] ④ Corrosion Intensity Calculation: Substitute relevant environmental data for the target city in the target year to calculate the corrosion intensity for that city in that year. Depending on the requirements, environmental data from one or more cities, one year, or multiple years can be substituted. The calculation results can be selected as the highest value, average value, or other processed results as needed.

[0057] Step 2: Establish a whole-vehicle road corrosion enhancement test system and determine the test methods applicable to this system.

[0058] The whole-vehicle road corrosion testing system primarily utilizes market corrosion intensity and past engineering experience to design test plans and test sites. The goal is to establish a corrosion testing system that meets market corrosion intensity requirements and fully reflects market performance. The establishment of a whole-vehicle road corrosion testing system includes the following steps:

[0059] ① Test conditions determination: The whole vehicle road corrosion test generally includes two parts: corrosion durability test and environmental accelerated corrosion test, namely, road accelerated corrosion test on different reinforced road sections and environmental alternating corrosion test in an environmental chamber (including at least salt spray test and damp heat alternating cycle test). The specific conditions need to be adjusted according to engineering experience and test site conditions.

[0060] ② Test plan determination: Based on the test intensity requirements, test site conditions, and staff arrangements. The test intensity is based on the market environment corrosion intensity calculated in step 1.

[0061] ③ The target number of cycles for the whole vehicle road corrosion testing system also needs to be calibrated, and the following formula must be satisfied:

[0062] D=αC (4)

[0063] In equation (4), C is the highest market environmental corrosion intensity obtained in step 1, D is the corrosion intensity required by the whole vehicle road enhanced corrosion test system, and α is the environmental intensity correction coefficient obtained by fitting the market corrosion intensity data with C.

[0064] H = C / D (5)

[0065] In equation (5), H represents the number of annual target cycles.

[0066] Market corrosion intensity data is obtained through monitoring the corrosion of the mounting brackets: By contacting car owners in target cities (generally selecting the cities with the highest corrosion intensity calculated from the environmental corrosion intensity and the cities with the highest vehicle market share), test mounting brackets are placed on all or some of the mounting bracket positions on their vehicles. The condition of the mounting brackets is checked regularly (generally every three months). After one year, the mounting brackets are removed, and the weight loss or corrosion depth of the mounting brackets is measured. This data is the market corrosion intensity data.

[0067] Feedback and Adjustment Process: Due to the dynamic changes in the natural environment (temperature, humidity, chloride ion concentration, etc.), the intensity varies from year to year, and the type and amount of de-icing salt used also differ annually. If air pollution is severe in a certain area, the content of acid ions in the air will increase significantly, leading to increased corrosion intensity; similarly, heavy snowfall in a certain area and the use of more de-icing salt on the roads will also cause increased corrosion intensity. We need to periodically adjust the annual cycle test number H based on the measured market corrosion intensity to accurately guide vehicle development. Simultaneously, we can adjust the position, material, and quantity of the de-icing pads based on corrosion complaints.

[0068] Step 3: Using the established testing system and methods, calculate the corrosion intensity of the vehicle under test.

[0069] The simulated dynamic vehicle corrosion intensity calculation system primarily calculates the simulated corrosion intensity of a vehicle using a full-vehicle road-enhanced corrosion testing system. The specific calculation process is as follows:

[0070] The vehicle under test was subjected to a full-vehicle road-enhanced corrosion test using the aforementioned vehicle road-enhanced corrosion testing system, and the corrosion performance was observed and recorded periodically. The test was stopped at the target cycle as needed, and the vehicle was disassembled to record the corrosion status in invisible areas.

[0071] S4. Based on the calculated vehicle corrosion intensity and standard corrosion spectrum, predict the vehicle corrosion life.

[0072] The methods for preparing standard corrosion spectra include:

[0073] ① Fabricate standard carbon steel / aluminum alloy / magnesium alloy test plates (specific material grades can be selected according to needs) and standard surface treatment process test plates (surface treatment processes include but are not limited to galvanizing, zinc-nickel plating, zinc-aluminum coating, painting, etc., specific process parameters can be selected according to needs); Selection of standard test plate materials: generally SPHC / Q235 hot-rolled pickled steel is used, or similar DC01 test plates with the highest vehicle usage ratio can be selected as needed, or materials commonly used in the mounting area can be used, such as DP1180 steel plate for the body area, or special materials to be verified can be used, such as 6061 aluminum alloy plate for aluminum alloy parts or AZ80 magnesium alloy plate for magnesium alloys.

[0074] ②Use salt spray chambers, environmental chambers, etc. to conduct neutral salt spray tests (NSS), cyclic salt spray tests (CCT), and copper ion accelerated tests (CASS) on standard test panels and standard surface treatment process test panels;

[0075] ③ Prepare standard corrosion charts based on the test results.

[0076] Different vehicle corrosion life calculation methods can be selected based on different assessment indicators:

[0077] Using the absence of rust as the evaluation criterion: Select all visible parts and calculate the corrosion life of each part by referring to the standard corrosion chart; use empirical formulas: Calculate the vehicle corrosion life CL. Where Lb, Le, and Lc represent the corrosion lives of components in the exterior, engine compartment, and chassis areas, respectively, and α... b α e α c These are the weighting coefficients, which are empirically selected as 5, 3, and 1 respectively.

[0078] Using non-perforation as the evaluation criterion: Select all parts and calculate the corrosion life of each part by referring to the standard corrosion spectrum; use empirical formulas: Calculate the vehicle corrosion life CL. Where LSM and LNSM represent the corrosion lives of sheet metal and non-sheet metal parts, respectively, and α... SM α NSM These are the weighting coefficients, which are empirically determined to be 6 and 1 respectively.

[0079] Using functional non-failure as the performance indicator: Select all parts and calculate the corrosion life of each part by referring to the standard corrosion spectrum. Use empirical formulas as a reference. Calculate the vehicle corrosion life CL. Where LKI and LNKI represent the corrosion lives of sheet metal and non-sheet metal parts, respectively, and α... KI α NKI These are the weighting coefficients, which are empirically determined to be 3 and 1 respectively.

[0080] Example:

[0081] In this embodiment, an automotive corrosion life prediction system is established according to the above method. For a new model, a tooling prototype is used to predict the corrosion life during the development stage. The prediction results show that: ① with no rust on the exterior as the evaluation index, the corrosion life of the vehicle is about 5.6 years; ② with no perforation as the evaluation index, the corrosion life of the vehicle is 11 years; ③ with no functional failure as the evaluation index, the corrosion life of the vehicle is 13 years.

[0082] (1) Establish an environmental corrosion intensity measurement model and calculate the environmental corrosion intensity.

[0083] The process of establishing the market environment corrosion intensity measurement model is as follows:

[0084]

[0085] In formula (1): D i D is the raw data for the atmospheric environment. iUB and D iLB As boundary values, the target interval range for the linear mapping [a1, a2] is set to [0.2, 0.8]. The least squares method is used for fitting, with the goal of minimizing the sum of squared errors, to calculate d. i ;

[0086]

[0087] In equation (2): d i For environment mapping parameters, ω i These are the weighting coefficients for environmental factors;

[0088] R = A·E + B (3)

[0089] In formula (3): R is the annual corrosion equivalent, E is the comprehensive factor of atmospheric environmental corrosivity, and A and B are substitution coefficients.

[0090] Based on climate data of 34 cities across the country released by the National Meteorological Center and Q235 weather station data (Beijing University of Science and Technology), typical climate cities in China were identified. The atmospheric comprehensive factor was calculated and regressed using data from the 34 cities (1984-2006): E = 0.31*d1 + 0.12*d2 + 0.03*d3 + 0*d4 + 0.75*d5 + 0.38*d6 + 0.84*d7; prediction model: R = 113.95E - 72.148; confidence level: 0.898; substituting environmental data from 31 provincial capital cities in 2014, the highest value of R in the final calculation result was 74.3 μm / year.

[0091] (2) Conduct enhanced corrosion tests on standard test plates in the laboratory and establish a standard corrosion spectrum.

[0092] Based on the above, a standard corrosion spectrum can be established.

[0093] (3) Establish enhanced corrosion testing methods and systems

[0094] The following factors need to be considered when determining the test plan: 1. Follow the basic principles of road-enhanced corrosion testing of whole vehicles, including at least corrosion durability and environmental accelerated corrosion testing procedures; 2. Arrange road-enhanced test cycles and adjust environmental accelerated corrosion test conditions in order to shorten the test cycle; 3. Combine the actual conditions of the test site, especially considering test sites under construction, in order to make effective use of test site resources.

[0095] The roads subjected to accelerated corrosion testing included different reinforced road sections:

[0096] Road A: Gravel road (50 km / h) → Gravel road (50 km / h) → Gravel road (50 km / h);

[0097] Route B: Saltwater Road (20km / h) → Saltwater Washboard Road (Salt Spraying) (10km / h) → Auxiliary Road → Saltwater Road (20km / h) → Saltwater Washboard Road (Salt Spraying) (10km / h);

[0098] Road C: Washboard road (50km / h) → Type C gravel road (30km / h) → Washboard road (50km / h) → Type C gravel road (30km / h) → Washboard road (50km / h) → Type C gravel road (30km / h) → Washboard road (50km / h);

[0099] Road D: Salt mud road (20km / h) → Auxiliary road → Salt mud road (20km / h);

[0100] Road E: Washboard road (50 km / h) → Type C gravel road (30 km / h) → Washboard road (50 km / h).

[0101] Through multiple design and simulation tests, the following test plan was determined: F = Pre-test inspection → Enhanced corrosion road test 1 → Salt spray test 1 → Enhanced corrosion road test 2 → Damp heat alternating cycle test → Salt spray test 2; each F constitutes one cycle, lasting 1 day. A cycle check is performed after each cycle. If the target number of cycles is reached, the entire vehicle is disassembled to evaluate the corrosion level of invisible areas; if the target number of cycles is not reached, the pre-test inspection is returned, and testing continues.

[0102] The pre-test checks include: safety checks, switch tests for opening components, and electrical function checks; the first enhanced corrosion road test includes: selecting any three road conditions from the above AEs for testing, and performing 3-5 cycles in a certain order; the first salt spray test includes: testing in a salt spray chamber for 1-2 hours; the second enhanced corrosion road test includes: selecting at least three road conditions from the above AEs for testing, and performing 1-3 cycles in a certain order; the damp heat alternating cycle test includes: testing for 5-8 hours under certain temperature and humidity conditions in an environmental chamber; the cycle period checks include: inspection of the mounting brackets, inspection of vehicle body scratches, evaluation of paint film thickness, and assessment of visible area corrosion level, etc.

[0103] The driving speed, length, test intensity, and travel time between each section are determined by the specific conditions of the test site. If the test site is changed, these parameters will change and need to be readjusted. The test sequence and number of repetitions for each section need to be adjusted and set by engineering personnel.

[0104] (4) Calculate the corrosion intensity of simulated dynamic vehicles

[0105] The target number of cycles for the whole vehicle road corrosion testing system also needs to be calibrated, and must satisfy the following formula:

[0106] D=αC (4)

[0107] In equation (4), C is the highest market environmental corrosion intensity obtained in step 1 (i.e., the urban environmental corrosion intensity corresponding to the most severe environment among 34 cities), D is the corrosion intensity that the whole vehicle road enhanced corrosion test system needs to meet; α is the environmental intensity correction coefficient obtained by fitting the market corrosion intensity data with C, the range of which is 0.2-0.8, and it can be initially set to 0.2; C = 0.0743 mm, and the calculated C test scheme = 0.01486 mm;

[0108] H = C / D (5)

[0109] In equation (5), H represents the number of annual target cycles, and H = 5 is calculated.

[0110] Therefore, the corrosion intensity of this test is 5 cycles / calendar year. That is, the whole vehicle is subjected to enhanced corrosion test according to this test method at the test center, and 5 cycles are equivalent to the vehicle operating in the most severe environment for 1 year.

[0111] (5) Predicting vehicle corrosion life

[0112] ① Using the absence of rust as the evaluation criterion: Select all visible parts and calculate the corrosion life of each part by referring to the standard corrosion chart. Use empirical formulas as a reference. Calculate the vehicle corrosion life CL. Where Lb, Le, and Lc represent the corrosion lives of components in the exterior, engine compartment, and chassis areas, respectively, and α...b α e α c These are the weighting coefficients, which our company uses based on experience and are 1, 1.7, and 5 respectively. Num represents the total number of selected parts.

[0113] Substituting the data below, we calculate CL = 5.62 years.

[0114] ② Using non-perforation as the evaluation criterion: Select all parts and calculate the corrosion life of each part by referring to the standard corrosion chart. Use empirical formulas: Calculate the vehicle corrosion life CL. Where LSM and LNSM represent the corrosion lives of sheet metal and non-sheet metal parts, respectively, and α... SM α NSM These are the weighting coefficients, which our company uses based on experience, and are 6 and 1 respectively.

[0115] Substituting the data below, we calculate CL = 11.03 years.

[0116] ③ Using functional non-failure as the evaluation indicator: Select all parts and calculate the corrosion life of each part by referring to the standard corrosion chart. Use empirical formulas as a reference. Calculate the vehicle corrosion life CL. Where LKI and LNKI represent the corrosion lives of sheet metal and non-sheet metal parts, respectively, and α... KI α NKI These are the weighting coefficients, which our company uses based on experience, and are 3 and 1 respectively.

[0117] Substituting the data below, we calculate CL = 13.06 years.

[0118]

[0119]

[0120] The above description is merely a preferred embodiment of the present invention, but the present invention is not limited to the specific embodiments described above. Those skilled in the art can make various modifications, additions, or substitutes with similar methods without departing from the principles of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A method of predicting the corrosion life of a vehicle, characterized in that, The prediction method comprises: S1, acquiring market environment corrosion intensity; S2, establishing a whole vehicle road strengthening corrosion test system, and determining a test method suitable for the test system; It is also necessary to calibrate the target cycle number of the whole vehicle road strengthening corrosion test system, and the following formula needs to be met: D = aC (4) In formula (4), C is the highest market environment corrosion intensity acquired in step 1, D is the corrosion intensity required to be met by the whole vehicle road strengthening corrosion test system, and a is an environmental intensity correction coefficient obtained by fitting market corrosion intensity data and C; H = C / D (5) In formula (5), H is the annual target cycle number; S3, using the determined test system and test method to measure and calculate the corrosion intensity of the vehicle to be measured; S4, combining the measured and calculated vehicle corrosion intensity and the standard corrosion spectrum to predict the vehicle corrosion life; Different vehicle corrosion life calculation methods can be selected according to different evaluation indexes: With appearance rust-free as the evaluation index: select all visible area parts, compare with standard corrosion atlas to calculate the corrosion life of each part, and then calculate the corrosion life of the vehicle; with the help of empirical formula: Calculate the corrosion life CL of the vehicle, where Lb, Le, and Lc are the corrosion life of each part in the body appearance area, engine compartment area, and chassis area, respectively, and α b , α e , and α c are weighting coefficients; With no perforation as the evaluation index: select all parts, compare with the standard corrosion atlas to calculate the corrosion life of each part, and then calculate the corrosion life of the vehicle; with the aid of empirical formula: Calculate the corrosion life CL of the vehicle, wherein LSM and LNSM are the corrosion lives of the sheet metal parts and the non-sheet metal parts respectively, and α SM , α NSM are weighting coefficients; With the functional failure as the evaluation index: select all parts, compare with the standard corrosion atlas to calculate the corrosion life of each part, and then calculate the corrosion life of the vehicle; with the help of empirical formula: Calculate the corrosion life CL of the vehicle, where LKI and LNKI are the corrosion life of sheet metal parts and non-sheet metal parts, respectively, and α KI , α NKI are weighting coefficients.

2. The method of predicting the corrosion life of a vehicle according to claim 1, characterized by, In step S1, the method for acquiring the market environment corrosion intensity is: A typical city in the target area is selected, the natural environment corrosion intensity of the target city is measured, and the relevant atmospheric environment data of the target city in the corresponding year is collected; A market environment corrosion intensity calculation model is established, the relevant environment data of the target city in the target year is substituted, and the market environment corrosion intensity of the city in the year is calculated.

3. The method of predicting the corrosion life of a vehicle according to claim 2, characterized by, The market environment corrosion intensity calculation model is established as follows: In formula (1): D i D iUB and D iLB are boundary values, the linear mapping target interval range [a1, a2] is taken as [0.2, 0.8], and the least square method is used for fitting, and the fitting calculation d i is carried out with the minimum error square sum as the target. In formula (2): d i is an environmental mapping parameter, ω i is an environmental factor weighting coefficient; R = A·E + B (3) In formula (3), R is the annual corrosion equivalent, E is the atmospheric environment corrosion comprehensive factor, and A and B are to-be-determined coefficients.

4. The method of predicting the corrosion life of a vehicle according to claim 2, characterized by, The atmospheric environmental data includes temperature, humidity, rainfall, sunshine duration, SO2 concentration, NO2 concentration and Cl - concentration.

5. The method of claim 1, wherein In step S2, the whole vehicle road strengthening corrosion test system comprises environmental accelerated corrosion tests in different strengthening road sections and corrosion durability tests in an environmental cabin.

6. The method of predicting the corrosion life of a vehicle according to claim 5, characterized by, In step S2, according to the market environment corrosion intensity acquired in step S1 and the test site conditions and staff arrangement, a test method suitable for the whole vehicle road strengthening corrosion test system is determined.

7. The method of predicting the corrosion life of a vehicle according to claim 6, characterized by, The test method comprises: Each single cycle is checked, and if the target cycle number is reached, the vehicle is disassembled, and the corrosion grade of the invisible area is evaluated; wherein, the single cycle step is: pre-test inspection → strengthening corrosion road test one → salt spray test one → strengthening corrosion road test two → wet and hot alternating cycle test → salt spray test two.

8. The method of predicting the corrosion life of a vehicle according to claim 1, characterized by, In step S4, the method for making the standard corrosion spectrum comprises: 1) making standard test plates and standard surface treatment process test plates; 2) respectively performing environmental corrosion tests on the standard test plates and the standard surface treatment process test plates; 3) making a standard corrosion spectrum according to the test results.

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