Vehicle body composite coating and design method thereof

Patent metadata

Field	Value
Publication number	US-10733339-B2
Application number	US-201515119318-A
Country	US
Kind code	B2
Filing date	Sep 22, 2015
Priority date	Sep 26, 2014
Publication date	Aug 4, 2020
Grant date	Aug 4, 2020

Abstract

A vehicle body composite coating, comprising, in succession, a polyurethane finishing coat, a polyurethane intermediate layer, a polyester putty and a micro-arc oxidation ceramic layer undercoat, wherein the micro-arc oxidation ceramic layer undercoat is on an aluminium substrate of the vehicle body. The design method of the vehicle body composite coating includes establishment of a physical model, selection of an optimal thickness ratio, preparation of the vehicle body composite coating and an erosion test. The vehicle body composite coating enhances the binding force between the whole coating system and the aluminium alloy substrate, reduces the possibility of shedding of the coating as a whole, and improves the anti-erosion performance of the vehicle body composite coating.

First claim

The invention claimed is:

1. A design method for a vehicle body composite coating, characterized in that the vehicle body composite coating comprises, in succession, a polyurethane topcoat, a polyurethane intermediate layer, a polyester putty and a micro-arc oxidation ceramic primer, wherein the micro-arc oxidation ceramic primer is coated on an aluminium substrate of the vehicle body, the method comprises the steps of:
S1. establishing a physical model based on the vehicle body composite coating, calculating a dynamic response of the vehicle body composite coatings with different thickness ratios under impact, and evaluating an anti-erosion capacity of the vehicle body composite coating by employing an element removal amount of the superficial coat—the polyurethane topcoat as well as a peeling force between the aluminium substrate of the vehicle body and the micro-arc oxidation ceramic layer as standards;
S2. selecting an optimal thickness ratio of the vehicle body composite coating based on the result of the calculation;
S3. preparing the vehicle body composite coating on the aluminium substrate of the vehicle body according to the optimal thickness ratio;
S4. performing an erosion test on the vehicle body composite coating, and comparing an anti-impact performance between the vehicle body composite coating and an original composite coating to determine the optimal thickness ratio of the vehicle body composite coating.

2. The design method according to claim 1 , characterized in that in the physical model, rigid pellets are selected as impacting particles, a Johnson-Cook constitutive model is selected for the polyurethane topcoat, and an elastoplastic constitutive model is selected for the polyurethane intermediate layer, the polyester putty and the micro-arc oxidation ceramic primer.

3. The design method according to claim 2 , characterized in that the impacting particles are pellets with a diameter of 95 μm˜105 μm, and having a speed of 90 m/s˜110 m/s, and an erosion angle is selected to be 25°˜35°.

4. The design method according to claim 2 , characterized in that the element removal amount of the polyurethane topcoat is calculated based on a cumulative damage rule, wherein a plastic strain of all the elements is calculated for each time step during the calculation, an element is removed when its plastic strain reaches a damage critical value in the calculation, and the element removal amount is counted after the calculation is completed.

5. The design method according to claim 2 , characterized in that the peeling force between the aluminium substrate of the vehicle body and the micro-arc oxidation ceramic primer is a resultant force of the interfacial tensile stress and shear stress between the aluminium substrate and the micro-arc oxidation ceramic primer when calculated, and the resultant force is used to characterize the peeling force in an impact process.

Assignees

• Crrc Qingdao Sifang Co Ltd

Inventors

• Zhang Shixin
• Wang Xiaocheng
• Wu Chuantian
• Zhang Zhanling
• Li Shitao
• Li Wen
• Meng Lichun
• Liu Shaoqing
• Deng Xiaojun

Classifications

• C09D167/00 Primary

  Coating compositions based on polyesters obtained by reactions forming a carboxylic ester link in the main chain (based on polyester-amides C09D177/12; based on polyester-imides C09D179/08); Coating compositions based on derivatives of such polymers · CPC title

• G06F30/15

  Vehicle, aircraft or watercraft design · CPC title

• C25D11/04

  of aluminium or alloys based thereon · CPC title

• G06F30/23 Primary

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title

• C09D175/04

  Polyurethanes · CPC title