CN-121992337-A - Nitride ceramic particle reinforced electric automobile battery pack bottom guard plate and manufacturing method thereof

Abstract

The invention discloses a nitride ceramic particle reinforced electric automobile battery pack bottom guard plate and a manufacturing method thereof, and belongs to the field of electric automobile battery technology and vehicle manufacturing. The invention adopts a CrMoAl steel sheet, polishes the surface of the sheet to remove oxidation, and takes out a sample after nitriding process treatment in a gas nitriding furnace and cooling to room temperature along with the furnace, thus obtaining the nitride ceramic particle reinforced electric automobile battery bottom guard plate. According to the invention, the ultra-deep nitride layers are formed on the two sides of the steel plate through the reinforcement of nitride ceramic particles, the non-nitride layers are arranged in the middle of the steel plate, and a sandwich structure of the nitride layers, the non-nitride layers and the nitride layers is formed, so that the steel plate has high hardness and toughness at the same time due to the existence of the double-layer nitride layers and the non-nitride layers in the middle, and can not only bear the conditions of broken stone splashing, road surface fluctuation collision and the like caused by external environment when being applied to a bottom guard plate of an electric automobile, but also prevent the damage to a battery pack caused by the conditions of bending, breaking and the like of the steel plate.

Inventors

• TONG WEIPING
• Chang Xiangpeng
• HUANG TIANXIANG

Assignees

• 东北大学

Dates

Publication Date

20260508

Application Date

20260409

Claims (7)

1. 1. The manufacturing method of the nitride ceramic particle reinforced electric automobile battery pack bottom guard plate is characterized by comprising the following steps of: and (3) polishing the surface of the sheet by adopting a CrMoAl steel sheet with the thickness of 1-5 mm to remove oxidation, carrying out nitriding process treatment in a gas nitriding furnace, cooling to room temperature along with the furnace, and taking out a sample to obtain the nitride ceramic particle reinforced electric automobile battery bottom guard plate.
2. 2. The method for manufacturing a nitride ceramic particle reinforced electric vehicle battery bottom guard plate according to claim 1, wherein the CrMoAl steel sheet comprises the following components in percentage by mass ,Cr：0.50%-2.00%、Al：0.40%-1.11%、Mo：0.10%-0.35%、Mn：0.30%-0.60%、C：0.17%-0.42%、Si：0.17%-0.45%、P：≤0.20%、S：≤0.20%、Ni：≤0.30%、Cu：≤0.20%,, the balance being Fe and unavoidable impurities.
3. 3. The method for manufacturing the nitride ceramic particle reinforced electric automobile battery bottom protection plate, according to claim 1, is characterized in that the nitriding process comprises the steps of placing a polished thin plate in a nitriding furnace, introducing ammonia gas for 20-30 min to uniform the furnace atmosphere, discharging the oxidizing atmosphere in the furnace, and adopting a strong permeation-diffusion-homogenization-strong permeation-diffusion multistage nitriding process.
4. 4. The method for manufacturing a nitride ceramic particle reinforced electric vehicle battery bottom guard plate according to claim 1, wherein the nitride ceramic particle reinforced electric vehicle battery bottom guard plate is of a sandwich structure of nitriding layer-non-nitriding layer, and nitriding layers with a thickness of 500-800 μm are formed on two sides of the thin plate respectively.
5. 5. The method for manufacturing the nitride ceramic particle reinforced electric automobile battery bottom protection plate according to claim 3, wherein the strong permeation temperature is 520-550 ℃, the diffusion temperature is 20-40 h, the diffusion temperature is 560-590 ℃, the homogenization temperature is 600-900 ℃ and the homogenization time is 2-4 h.
6. 6. A nitride ceramic particle reinforced electric vehicle battery pack bottom guard plate manufactured by the method of any one of claims 1-5.
7. 7. The application of the nitride ceramic particle reinforced electric automobile battery pack bottom guard plate is characterized in that the nitride ceramic particle reinforced electric automobile battery pack bottom guard plate is arranged below a battery pack and plays a role in bearing and protecting the battery pack.

Description

Nitride ceramic particle reinforced electric automobile battery pack bottom guard plate and manufacturing method thereof Technical Field The invention belongs to the field of electric automobile battery technology and vehicle manufacturing, and particularly relates to a nitride ceramic particle reinforced electric automobile battery pack bottom guard plate and a manufacturing method thereof. Background At present, the rapid development of electric automobiles is important for the protection of core-battery packs of the electric automobiles. Generally, an electric vehicle battery pack is installed under a seat, i.e., on a chassis of the vehicle, and the battery is generally covered to protect the battery and prevent the battery pack from fire caused by short circuit or the like. In particular, in the lower part of the battery pack, due to the fact that the battery pack is close to the ground, damage to the battery pack caused by fluctuation of the ground and splashing of stones often occurs, and in order to prevent the damage to the battery pack and the electric vehicle, it is necessary to manufacture the bottom guard plate of the battery pack of the electric vehicle, which has high hardness, high strength, abrasion resistance and impact resistance, from a proper material. The prior battery pack bottom guard board mainly comprises (1) a steel plate with the lowest cost, the strongest anti-impact and anti-puncture capabilities and the most mature process. But has the disadvantages of larger weight, serious influence on cruising and easy corrosion. (2) An aluminum alloy sheet which has the advantage of light weight (about 60% lighter than steel), is excellent in corrosion resistance and impact resistance. But the cost is higher than that of steel, the hardness and strength are poorer, the deformation is easy, and the extreme puncture resistance is weaker than that of steel. (3) Ceramic materials, which have good strength and are light, but poor toughness and impact resistance, are brittle during collisions. (4) Composite shields, such as fiberglass reinforced polymers, have the advantages of light weight, corrosion resistance, high design freedom, and integrated structure. But have a weak resistance to multiple impacts and sustained wear, and early or low-end vehicle-type applications are more numerous and are now being replaced. (5) The carbon fiber reinforced composite material has the advantages of extremely light weight, high specific strength, high specific modulus and high design freedom. But has extremely high cost, is difficult to detect after damage and is difficult to maintain, and is often used for super sports cars and top-grade performance cars. In general, the traditional steel plate has higher overall cost performance and heavier weight, so that the traditional steel plate cannot be qualified for the working condition of the electric automobile at present, wherein the electric automobile has the main advantages of low energy consumption and high endurance. Although the aluminum alloy has the advantage of light weight, the aluminum alloy is softer in texture and lower in hardness, and is easy to deform under the condition that a bottom guard plate of the battery pack of the electric vehicle possibly collides, so that the battery pack is extruded upwards, the conditions of internal short circuit, spontaneous combustion and the like of the battery pack are easily caused, and the driving safety is endangered. The ceramic material has a relatively high hardness on the surface, but is brittle and is easily broken when being impacted. However, the nonmetallic materials have been developed rapidly in recent years, but the manufacturing cost is high, and long routes are still required at present, which are mainly competitive with low price and high cost performance of electric automobiles. Disclosure of Invention Aiming at the development and application conditions of the prior electric automobile battery pack bottom guard plate, the invention provides an electric automobile battery pack bottom guard plate with a sandwich structure, wherein nitride ceramic particles are reinforced to form ultra-deep nitriding layers on two sides of the plate, an un-nitrided layer is arranged in the middle of the plate, so that the sandwich structure is formed, after nitriding treatment, high-hardness and high-strength layers with the thickness of 500-800 mu m are arranged on two sides of the bottom guard plate, the bottom guard plate has the advantages of corrosion resistance and light weight, the middle un-nitrided layer can provide better toughness for the bottom guard plate, so that the whole plate has high hardness and toughness, and when the electric automobile battery pack bottom guard plate is applied to the electric automobile bottom guard plate, the electric automobile battery pack bottom guard plate can bear the conditions of broken stone splashing, road surface fluctuation collision and the like caused by exte