KR-20260065238-A - Method for evaluating painting performance using image analysis

KR20260065238AKR 20260065238 AKR20260065238 AKR 20260065238AKR-20260065238-A

Abstract

A method for evaluating paint performance using image analysis is disclosed. The method for evaluating paint performance using image analysis comprises the steps of: preparing a specimen coated with zinc and a tensile testing machine; fixing the prepared specimen to the tensile testing machine and setting the current tensile load and displacement values to zero; performing a test by applying a tensile load to the specimen fixed to the tensile testing machine through the control of the tensile testing machine; collecting tensile load and displacement data measured during the test; stopping the test when a target displacement of a preset size is measured; and separating the specimen from the tensile testing machine upon stopping the test and observing whether the paint surface is damaged.

Inventors

심천식
위성국
노희창

Assignees

국립목포대학교산학협력단

Dates

Publication Date: 20260508
Application Date: 20241101

Claims (7)

In a method for evaluating paint performance using image analysis, Step of preparing a zinc-coated specimen and a tensile testing machine; A step of fixing the above-prepared specimen to the above-prepared tensile testing machine and then setting the current tensile load value and displacement value to zero; A step of performing a test by applying a tensile load to the specimen fixed to the tensile testing machine through the control of the tensile testing machine; A step of collecting tensile load and displacement data measured during the above test; A step of stopping the test when a target displacement of a preset size is measured; and A method for evaluating paint performance using image analysis, comprising the step of separating the specimen from the tensile testing machine following the cessation of the above test and observing whether the paint surface is damaged.
In paragraph 1, The step of performing the above test is, A method for evaluating coating performance using image analysis, characterized by applying a tensile load to a specimen through displacement control up to a target displacement exceeding the yield point of the specimen, and setting the test speed to 1 mm/min.
In paragraph 1, The step of stopping the above test is, A method for evaluating coating performance using image analysis, characterized by stopping the test at target displacements of 3mm, 5mm, 10mm, 20mm, and 30mm, respectively, and lowering the tensile load to 0.
In paragraph 1, The step of observing whether the above-mentioned painted surface is damaged is, A method for evaluating coating performance using image analysis, characterized by magnifying the gage section of the specimen using an optical microscope set and performing a visual inspection of microcracks.
In paragraph 1, The above coating performance evaluation method is, Step of preparing the brine; A step of spraying the prepared brine onto the surface of the specimen separated from the tensile testing machine and the specimen that has not undergone tensile testing at every hour for a preset time; A step of acquiring a surface image of the specimen sprayed with the brine using an optical microscope set; and A method for evaluating coating performance using image analysis, characterized by further including the step of performing image analysis on the acquired surface image using an image analysis program to inspect the surface of the specimen sprayed with salt water.
In paragraph 5, The step of inspecting the surface of the specimen sprayed with the above-mentioned salt water is, A method for evaluating coating performance using image analysis, characterized by using the above image analysis program to distinguish a damaged coating area in the acquired surface image and calculating the area of the damaged coating area.
In paragraph 5, The step of inspecting the surface of the specimen sprayed with the above-mentioned salt water is, A method for evaluating coating performance using image analysis, characterized by evaluating the error by comparing the results of image analysis of the surface images of a specimen separated from the above-mentioned tensile testing machine and a specimen that has not undergone the above-mentioned tensile test.

Description

Method for evaluating painting performance using image analysis The present invention relates to a method for evaluating coating performance using image analysis. With the tightening of regulations on greenhouse gases (GHG), the demand for propulsion vessels utilizing eco-friendly fuels is on the rise. When methanol is used as fuel, sulfur oxides are reduced by 99%, nitrogen oxides by 80%, and greenhouse gases by 25% compared to conventional ship fuels. Furthermore, it can be stored in a liquid state at room temperature and pressure, and the technical difficulty is not high compared to LNG and LPG fuels. In addition, it is emerging as a safe fuel due to its relatively lower toxicity compared to ammonia. However, methanol is a highly corrosive substance. However, in order to secure price competitiveness, the material of the fuel storage tank is designed using zinc coating on general classification society-approved structural steel instead of expensive stainless steel (SUS 316L), and rectangular fuel tanks are designed using shipyard equipment and materials. Since coated fuel storage tanks must maintain the integrity of the coating film against structural deformation of the hull caused by various loads during ship operation, it is necessary to inspect whether the performance is satisfied. In addition, since classification society requirements and paint manufacturer guidelines regarding the allowable variation of zinc-coated methanol fuel storage tanks are unclear, verification of the structural safety of methanol fuel storage tanks is required. FIG. 1 is a diagram schematically illustrating a method for evaluating coating performance using image analysis according to an embodiment of the present invention. FIG. 2 is a diagram schematically illustrating a method for evaluating coating performance using image analysis according to another embodiment of the present invention. FIGS. 3 to 11 are drawings for explaining a method for evaluating coating performance using image analysis according to an embodiment of the present invention. As used in this specification, singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "composed" or "comprising" should not be interpreted as necessarily including all of the various components or steps described in the specification, and should be interpreted as meaning that some of the components or steps may be excluded, or that additional components or steps may be included. Furthermore, terms such as "...part," "module," etc., as used in the specification refer to a unit that processes at least one function or operation, which may be implemented in hardware or software, or a combination of hardware and software. Hereinafter, various embodiments of the present invention will be described in detail with reference to the attached drawings. FIG. 1 is a schematic illustration of a method for evaluating paint performance using image analysis according to an embodiment of the present invention, FIG. 2 is a schematic illustration of a method for evaluating paint performance using image analysis according to another embodiment of the present invention, and FIG. 3 to 11 are drawings for explaining a method for evaluating paint performance using image analysis according to an embodiment of the present invention. Hereinafter, a method for evaluating paint performance using image analysis according to an embodiment of the present invention will be described with reference to FIG. 1, with reference to FIG. 2 to 11. In step S110, a zinc-coated specimen and a tensile testing machine are prepared. Here, the zinc-coated specimen can be manufactured by coating zinc onto steel used in shipbuilding, shipbuilding, or classification society steel. Additionally, as shown in FIG. 3, the specimen can be manufactured to be divided into a grip area and a painting area. Furthermore, as shown in FIG. 4, unlike a general tensile test, since a coating is applied, the specimen can be manufactured with an increased dimensional scale due to the special nature of the gage section of the test. In addition, the tensile testing machine may be an MTS universal testing machine manufactured by MTS, as shown in Fig. 5. The MTS universal testing machine has a loading capacity of ±2,500 kN/220 kip dynamically and ±2,750 kN/264 kip statically, a spacing between columns of 800 mm, a T-slot platen of 1,300 * 2,000 mm, and can perform tensile and compression tests, fatigue tests, and three-point bending tests. The control elements are displacement, load, and strain. The maximum specimen height is approximately 3,500 mm, and for flat surfaces, W is 300, H is 3,500, and T is 0~100 mm, and for circular surfaces, H is 3,500, and T is 30~100 mm. In step S120, after fixing the prepared specimen to the tensile testing machine, the current tensile load and displacement values are set to zero. Here, the prepared specimen can be fixed to the grip portion of th