Enhancement of Coating Features by Supporting Zinc-Based Coating with Cataphoresis Process: Effect of Acidity and Coating Thickness on the Coating Quality

Year 2024, Volume: 27 Issue: 5, 1761 - 1772

Adife Şeyda Yargıç , Bünyamin Eren , Nurgül Özbay

https://doi.org/10.2339/politeknik.1199586

Cited By: 1

Abstract

In this work, two hot-forged cast materials that are often used in the automobile sector were employed to produce cast elements with enhanced corrosion performance at low microns by combining two forms of cost-effective coatings (zinc + cataphoresis). In the context of the investigation, firstly 5-8 µm or 12-15 µm zinc-coating in an alkaline (Zn, Zn-Fe, Zn-Ni) or an acidic (Zn, Zn-Ni) environment, followed by 20-25 µm cataphoresis-coating were performed on GGG40 cast-parts. Ink, hogabom, shock, pull-off adhesion, water resistance, salt spray, stone impact, cyclic-corrosion, and scab-corrosion performance tests were implemented for characterization. In addition, the zinc-coating thickness and the phosphate-crystal appearance were evaluated in the x-ray diffraction laminography instrument and the scanning electron microscope. The tensile strengths were determined by the pull-off adhesion test between 171 and 433 psi. The coating thicknesses of zinc-coated parts in alkaline and acidic environments were assigned in the range of 5.88-7.18 µm and 12.10-12.96 µm. Due to the characterization results; it was deduced that the cataphoresis-coating after all zinc-based-coatings under alkaline medium did not afford the required quality and corrosion protection, while cast parts coated under acidic medium before cataphoresis-coating gave appropriate corrosion performance, thus the low-cost coatings could be performed with the eligible properties.

Keywords

Cast materials, cataphoresis coating, corrosion performance, acidic/alkaline zinc-based coatings.

Supporting Institution

TÜBİTAK

Project Number

3180632

Thanks

This study was supported as part of the TÜBİTAK 3180632 project carried out by Uzman Cataphoresis Surface Coating Industry Trade Inc., and the authors would like to thank TÜBİTAK and Uzman Cataphoresis Surface Coating Industry Trade Inc.

Çinko-Esaslı Kaplamanın Kataforez Prosesi ile Desteklenerek Kaplama Özelliklerinin Geliştirilmesi: Asitlik ve Kaplama Kalınlığının Kaplama Kalitesine Etkisi

Abstract

Bu çalışmada, otomobil sektöründe sıklıkla kullanılan iki sıcak-dövme döküm malzeme, uygun maliyetli iki kaplama formunun (çinko + kataforez) birleştirilmesiyle düşük mikronlarda geliştirilmiş korozyon performansına sahip döküm elemanları üretmek için kullanılmıştır. Araştırma kapsamında, GGG40 döküm malzemeleri üzerine önce alkali (Zn, Zn-Fe, Zn-Ni) veya asidik (Zn, Zn-Ni) ortamda 5-8 µm veya 12-15 µm çinko-kaplama, ardından 20- 25 µm kataforez-kaplama uygulanmıştır. Karakterizasyon için mürekkep, hogabom, şok, pull-off adhezyon, su direnci, tuz sisi, taş çarpma, çevrimsel-korozyon ve scab-korozyonu performans testleri yapılmıştır. Ayrıca çinko-kaplama kalınlığı ve fosfat-kristal görünümü, x-ışını kırınım laminografi cihazında ve taramalı elektron mikroskobunda değerlendirilmiştir. Çekme dayanımları, 171 ve 433 psi arasında çekme yapışma testi ile belirlenmiştir. Alkali ve asidik ortamlarda çinko-kaplı parçaların kaplama kalınlıkları 5,88-7,18 µm ve 12,10-12,96 µm aralığında ölçülmüştür. Karakterizasyon sonuçlarına göre; alkali ortam altında tüm çinko-esaslı-kaplamalardan sonra uygulanan kataforez-kaplamanın gerekli kaliteyi ve korozyon korumasını sağlamadığı, buna karşılık kataforez-kaplamadan önce asidik ortam altında kaplanan döküm parçaların uygun korozyon performansı gösterdiği sonucuna varılmış, dolayısıyla istenilen özelliklere sahip düşük-maliyetli kaplamaların yapılabileceği belirlenmiştir.

Keywords

Döküm malzemeler, kataforez kaplama, korozyon performansı, asidik/alkali çinko-esaslı kaplamalar.

Project Number

3180632

References

• [1] Ganesan S., Prabhu G. and Popov B. N., “Electrodeposition and characterization of Zn‐Mn coatings for corrosion protection”, Surface and Coatings Technology, 238: 143-151, (2014).
• [2] Lawrance J. D., “Electroplating Engineering Handbook”, 4th ed., New York, (1963).
• [3] Zaki N., Frederick Gumm Chemical Company, Inc.; Zinc Alloy Plating, Surface Engineering (Introduction) Volume 5; ASTM.
• [4] Kılınç M., “The investigation of the effect of dublex coating on the corrosion and life test of solvent based and water based flake coating applications on cataphoresis coating”, Master Thesis, Eskişehir Technical University, Institute of Science and Technology, (2019).
• [5] Can A., “, Examining the effect of duplex coating on corrosion and life testing with solvent based lamelled coating on alkaline and alloy zinc coating”, Master Thesis, Eskişehir Technical University, Institute of Science and Technology, (2019).
• [6] Ekinoks Kimya Cleanox 1972 TDS, “The application procedure of the strongly alkaline degreasing material used for iron, steel, aluminum, and zinc surfaces in the metal industry and automobile industry by dipping and spraying method”, (2018).
• [7] Uzman Cataphoresis Surface Coating Industry Trade Inc., “Reports of surface cleaning, zinc and cataphoresis coating procedures”, (2019).
• [8] Ekinoks Kimya Alukleen CV TDS, “Surface cleaning procedure of metals and alloys such as aluminum, copper, brass, zamak”, (2017).
• [9] Ekinoks Kimya Cleanox E TDS, “Electrolytic degreasing procedure in metal and automobile industries”, (2019).
• [10] Eser Kimya ES/FE 36 TDS, “Cyanide-free alkaline zinc-iron plating process”, (2017).
• [11] Eser Kimya ES/F1 TDS, “Cyanide-free alkaline zinc plating process”, (2017).
• [12] Eser Kimya ES/RKR TDS, “Acidic zinc plating process”, (2018).
• [13] Eser Kimya ES/RKR-NI TDS, “Acidic zinc-nickel plating process”, (2018).
• [14] Eser Kimya ES/ZN-NI Plus TDS, “Alkaline zinc-nickel plating process”, (2017).
• [15] Chemetall Gardobond AP9809 TDS, “Liquid, phosphorous-free pre-treatment for multi-metal applications”, (2017).
• [16] Chemetall Gardobond 24T TDS, “A manganese modified low zinc phosphating process for steel and galvanized steel materials”, (2018).
• [17] Chemetall Gardolene V 6513 TDS, “Activating pre-rinsing agent for metal surfaces applied by immersion or spray prior to phosphating”, (2017).
• [18] Ppg CP458A TDS, “Electrocoating Process”, (2017).
• [19] Ppg Powercon P6200 TDS, “Electrocoating Process”, (2018).
• [20] International Standard ISO 8296, “Plastics – Film and sheeting – Determination of wetting tension”, Geneva, (2003).
• [21] NOF Metal Coatings Group, “GEOMET 321/500 Technical manual (EN)”, (2017).
• [22] Adhesion Test 50765, “Metallic Material Surface Treatments Electrolytic Plating and Chemical Coating Heat Shock Adhesion Test”, (1990).
• [23] International Standard ISO 3497, “Metallic coatings - Measurement of coating thickness - X-ray spectrometric methods”, (2001).
• [24] Volvo car corporation test standard VCS 5740,1049, “Phosphating”, (2011).
• [25] ASTM D4541 Standart test method, “Pull-Off Strength of Coating Using Portable Adhesion Testers”, (2017).
• [26] Fiat Auto Normazione Material Standart 50470, “Water Resistance Test for Decorations and Paints”, (2005).
• [27] ASTM B117 Standart Method, “Salt Spray (Spray) Testing”, (1939).
• [28] International Standard DIN EN ISO 9227, “Corrosion tests in artificial atmospheres – Salt spray tests”, (2006).
• [29] International Standard SAE J400, “Surface vehicle recommended practice”, (2012).
• [30] Test standard PV1200, “Testing of resistance to environmental cycle test (+80/-40) °C”, (2004).
• [31] Fiat Auto Normazione Material Standart 50493/04, “Determination of the resistance of organic coatings to the propagation of bubble under skin corrosion (scab in door)”.