• Title/Summary/Keyword: metallic paint

Search Result 19, Processing Time 0.021 seconds

An Experimental Approach for Modeling the Appearance of Metallic Painted Surfaces (메탈릭 페인트로 코팅된 재질의 모델링 방법에 관한 연구)

  • Chowdhury, Mijanur Rahaman;Kim, Kang-Yeon;Yoo, Hyun-Jin;Ko, Kwang-Hee;Lee, Kwan-H.
    • 한국HCI학회:학술대회논문집
    • /
    • 2007.02a
    • /
    • pp.1037-1044
    • /
    • 2007
  • Metallic paint is one of the most widely used coating in automotive, cosmetic and other applications because of its well-known ability to give a product realistic look which creates widespread consumer appeal. But, this coating has complicated subsurface structure which includes pigments, flakes, and transparent clearcoat. Though various analytic reflection models are available to simulate appearance of various surfaces, it is difficult to select an appropriate reflection model with faithful parameters for simulating this coating due to the complex subsurface structure of metallic paints. This paper presents a framework for accurate modeling of metallic coating by determining an appropriate reflection model among various existing BRDF (Bidirectional Reflectance Distribution Function) models. The selection of the appropriate model is achieved by measuring BRDF of various metallic paint samples using a BRDF measuring device i.e. gonioreflectometer and fitting an existing model to the measured data. Then, this model is effectively realized by rendering metallic painted surfaces. We believe that this framework can serve as a guide for those who wants to render metallic painted surfaces accurately with analytic BRDF model without expending time on extracting BRDF data using gonioreflectometer from real metallic paint sample.

  • PDF

Introduction of Computer Simulation for BIW Electrocoating Process (BIW 전착도장에서의 컴퓨터 시뮬레이션 적용사례)

  • Sohn, DaeHong;Jung, HiZean;Ahn, SeungHo;Kim, ByungSu;Kim, JungYeon;Choi, ByungSam
    • Corrosion Science and Technology
    • /
    • v.15 no.2
    • /
    • pp.78-83
    • /
    • 2016
  • The e-coating to inhibit induced corrosion can deposit a coating not only on the exterior surface but also on the inside of whole metallic components of body-in-white (BIW). But it is difficult to deposit paint films on the inside area because metallic components are multi layered. It may cause shortness of e-coating thickness. The only way to properly verify e-coating thickness is by performing the use of tear-down prototypes. When paint films' thickness is inadequate, a structural modification on each metallic component is needed. Verification of the thickness improvement for a structural modification requires much manual effort and leads to increasing development time. Recently, the simulation technology has been developed to predict the e-coating thickness in e-coating field. By applying the simulation to BIW, improvement in paint thickness quality and shortening of development period are expected. The paper explains a validated solution that allows simulating the effect of design changes to the e-coating thickness and current density, thereby delivering results within a time frame of a few days.

Feasibility study of wide-band low-profile ultrasonic sensor with flexible piezoelectric paint

  • Li, Xin;Zhang, Yunfeng
    • Smart Structures and Systems
    • /
    • v.4 no.5
    • /
    • pp.565-582
    • /
    • 2008
  • This paper presents a feasibility study of flexible piezoelectric paint for use in wide-band low-profile surface-mount or embeddable ultrasonic sensor for in situ structural health monitoring. Piezoelectric paint is a piezoelectric composite with 0-3 connectivity. Because of its ease of application, piezoelectric paint can be readily fabricated into sensing element with complex pattern. This study examines the characteristics of piezoelectric paint in acoustic emission signal and ultrasonic guided wave sensing. A series of ultrasonic tests including pitch catch and pencil break tests were performed to validate the ultrasonic wave sensing capability of piezoelectric paint. The results of finite element simulation of ultrasonic wave propagation, and acoustic emission generated by a pencil lead break on an aluminum plate are also presented in this paper along with corresponding experimental data. Based on the preliminary experimental results, the piezoelectric paint appears to offer a promising sensing material for use in real-time monitoring of crack initiation and propagation in both metallic and composite structures.

Development of Paint-free Metallic Plastic Material for Automotive Parts (자동차 부품용 무도장 메탈릭 플라스틱 소재 개발)

  • Choi, Min Jin;Cho, Jeong-Min;Choi, Young Ho;Choi, Min Ho;Lee, Choon Soo;Sung, Han Ki;Lee, Kyoung Sil;Park, Ki Hun;Hwang, Se Jong
    • Korean Chemical Engineering Research
    • /
    • v.60 no.2
    • /
    • pp.295-299
    • /
    • 2022
  • In this paper, paint-free metallic plastic material, polypropylene (PP) and acrylonitrile styrene acrylate (ASA) materials were investigated on the applications for bumper skid plate and outside mirror housing parts. In order to maximize metallic effect, type, size and content of aluminum pigment were optimized based on flop index. Hybrid aluminum pigments with different aspect ratios were used to conceal weld lines. By controlling the fluidity of the material, the flow mark problem, generated on the surface of the part, was resolved. We also investigated the surface defects of flow and weld lines by using the developed modeling and simulation.

A study on the color controlled of painter's work (페인트 도장공사의 색관리에 관한 연구)

  • Shim, Myung-Sup;Lee, Hyun-Jeong
    • Journal of the Korea Institute of Building Construction
    • /
    • v.3 no.1
    • /
    • pp.107-114
    • /
    • 2003
  • This study aims to find methods that prevents aging of buildings paint coating and that limits defects in construction. Defects in painting can occur in four stages: pure paint, during painting, after the paint coating has dried, and after some period of time has passed after coating. Paint may become bad due to precipitation of pigments, formation of membranes, and seeding during manufacturing. Therefore, it is important that the paint is well mixed and kept airtight at a cool, dark place. Indents, paint brush strokes, orange peel, separation of colors, and paint running and spreading during the paint work process can be prevented by using high quality materials and applying a high-level of construction method. After the paint coating has dried, boiling, yellowing, poor drying, poor bonding, and/or glen deficiency may occur. These are influenced by the levels of cleanness of the dried product, drying temperature and hydration. Then, when the coating has been left dried for some period of time, cracking, peeling, scaling, swelling, discoloring, and/or rusting may develop due to the ultraviolet and contaminants in the air. Since these defects occur due to inappropriate construction schedule and/or hot and humid condition, one must use weatherproof materials. Furthermore, poor paint color may be caused by contamination in the sample plate, discoloration, and/or discrepancies in colors which are due to material differences, level of glossiness, degree of dispersion, dual color property of metallic colors, precipitation of pigments, etc. One should achieve reduction in construction cost and effectiveness in paint work by limiting contaminations in the construction site and strictly observing to construction regulations.

Influences of Coatings and Solution Corrosivity on Cathodic Protection of Metallic Materials

  • Yoo, Y.R.;Chang, H.Y.;Jin, T.E.;Kim, Y.S.
    • Corrosion Science and Technology
    • /
    • v.5 no.3
    • /
    • pp.106-111
    • /
    • 2006
  • Painting has protected metallic stack but the paint films may be degraded and corrosion problem can be arisen. To protect the painted metal stack, cathodic protection can be applied. If cathodic protection is applied to bare metal, only small area may be protected. However, if cathodic protection is applied to painted metal surface, large area can be protected and the lifetime of paint films can be extended. High corrosion resistant alloys were corroded at a Flue Gas Desulfurization (FGD) facility of power plant within a short period and thus cathodic protection can be used to protect these metals. On the base of computer simulation, if cathodic protection is applied to bare metal in a FGD environment, it was estimated that applied current could almost be spent to protect area near the anode. However, if cathodic protection is applied to high resistant-coated metal, the much larger area from the anode could be effectively protected.

The fire-risks of cost-optimized steel structures: Fire-resistant and hot-rolled carbon steel

  • Garcia, Harkaitz;Cuadrado, Jesus;Biezma, Maria V.;Calderon, Inigo
    • Structural Engineering and Mechanics
    • /
    • v.78 no.1
    • /
    • pp.67-75
    • /
    • 2021
  • This work studies the behaviour of a steel portal frame selection under fire exposure, considering both span lengths and fire exposure times as variables. Such structures combine carbon steel (S275), fireproof micro-alloyed steel (FR), and coatings of intumescent paint with variable thicknesses, improving thereby the flame retardant behaviour of the steel structure. Thus, the main contribution of this study is the optimization of the portal frames by combining both steels, analysing the resulting costs influence on the final dimensions. Besides, the topological optimization of each steel component within the structure is also defined, in accordance with the following variables: weather conditions, span, paint thickness, and cost of steel. The results mainly confirmed that using both FR and S275 grades with intumescent painting is the Pareto optimum when considering performance, feasibility and costs of such portal frames widely used for industrial facilities.

The study of accelerating method for Mobile Product with sweat resistance (Mobile 제품 도장의 내한성(耐汗性) 가속 평가법 개발)

  • Park, Kwang-Young;Lim, Sung-Gyun;Cha, Seung-Kyu
    • Journal of Applied Reliability
    • /
    • v.6 no.3
    • /
    • pp.205-212
    • /
    • 2006
  • The purpose of this article is about the accelerated product-reliability-test method of the changing colors of mobile products, which are majorly from the frequent touching of sweating fingers. Such problems of changing colors of mobile products have found mostly In metallic paint containing aluminum paste pigments. Also we found that the color of Al Paste is changed by human sweat. Therefore, the accelerated experimental method has been tested as follow: applying the various concentration of lactic acid, which is the changing color components from human sweat, and deeping the testing sample under temperature of $60^{\circ}C$ in dilutelactic acid with water. From the series of tests, the most optimum concentration of lacticacid has been obtained in 10wt% and the sample is observed to be almost same effect as natural changing of colors by human touching after the test. It has been also confirmed from the cross-sectional analysis. In detail, the testing sample has changed its color in 48hr by changing color effect of Alpaste with 10 wt% of lactic acid, and the digit of $\Delta$ E has measured 10.9 after the test.

  • PDF

Visualization of Crack Propagation and Fracture Transition in Bulk Metallic Glass using Mechano-Luminescence (압광을 이용한 금속계 비정질 합금의 균열전파 및 파괴전이 현상 가시화 연구)

  • Kim, Ji-Sik
    • Transactions of Materials Processing
    • /
    • v.20 no.4
    • /
    • pp.303-308
    • /
    • 2011
  • Using a mechano-luminescent(ML) paint, which allows the visualization of fast propagating crack under conventional loading conditions, a catastrophic fracture mechanism associated to crack tip melting and wake bridging in bulk metallic glass, is described in this paper. Fracture occurs in two steps with, first, crack initiation from the mechanically machined sharp notch tip in a rectangular shaped compact tension specimen and melting of its tip due to intense shear deformation within very few deformation bands. Then, the crystalline phase in the glass matrix gradually converts the molten crack into a conventional bridged crack as it propagates.

Spray Characteristics on the Electrostatic Rotating Bell Applicator

  • Im, Kyoung-Su;Lai, Ming-Chia;Yoon, Suck-Ju
    • Journal of Mechanical Science and Technology
    • /
    • v.17 no.12
    • /
    • pp.2053-2065
    • /
    • 2003
  • The current trend in automotive finishing industry is to use more electrostatic rotating bell (ESRB) need space to their higher transfer efficiency. The flow physics related with the transfer efficiency is strongly influenced by operating parameters. In order to improve their high transfer efficiency without compromising the coating quality, a better understanding is necessary to the ESRB application of metallic basecoat painting for the automobile exterior. This paper presents the results from experimental investigation of the ESRB spray to apply water-borne painting. The visualization, the droplet size, and velocity measurements of the spray flow were conducted under the operating conditions such as liquid flow rate, shaping airflow rate, bell rotational speed, and electrostatic voltage setting. The optical techniques used in here were a microscopic and light sheet visualization by a copper vapor laser, and a phase Doppler particle analyzer (PDPA) system. Water was used as paint surrogate for simplicity. The results show that the bell rotating speed is the most important influencing parameter for atomization processes. Liquid flow rate and shaping airflow rate significantly influence the spray structure. Based on the microscopic visualization, the atomization process occurs in ligament breakup mode, which is one of three atomization modes in rotating atomizer. In the spray transport zone, droplets tend to distribute according to size with the larger drops on the outer periphery of spray. In addition, the results of present study provide detailed information on the paint spray structure and transfer processes.