Substrate Protection for Corrosion Prevention: Substrate Protection for Corrosion Prevention I
Program Organizers: Mary Lyn Lim, PPG Industries; Cortney Chalifoux, Exponent; Qixin Zhou, The University of Akron; Kylee Fazende, NSWC Carderock Division; Raul Rebak, GE Global Research; Tushar Borkar, Cleveland State University
Monday 8:00 AM
November 2, 2020
Room: Virtual Meeting Room 27
Location: MS&T Virtual
Session Chair: Mary Lyn Lim, PPG Industries; Qixin Zhou, University of Akron
8:00 AM
Characterizations of Corrosion Tested CFRC-AZ31B Joint by Friction Self-pierce Riveting Process: Yong Chae Lim1; Jiheon Jun1; Jian Chen1; Michael Brady1; Donovan Leonard1; Zhili Feng1; 1Oak Ridge National Laboratory
For improved fuel efficiency, advanced high specific strength materials such as magnesium alloys and carbon fiber reinforced composite (CFRC) can be employed for lightweight transportation. However, joining and corrosion (particularly galvanic corrosion) of these dissimilar materials are critical technical obstacles for this application. In the present work, we adapted a unique friction self-piercing rivet process to spot join a CFRC to magnesium alloy AZ31B at a laboratory coupon scale. Corrosion behavior of this dissimilar joint was evaluated by 0.1 M NaCl immersion testing with different exposure times. Different surface coatings/modifications were applied to the rivet material in an attempt to minimize galvanic effects at the rivet/multi-material interface. Post exposure joints were evaluated by lap shear tensile testing, corrosion depth assessment, and optical and electron microscopy. Surface coatings/modification of the rivet material showed potential to reduce galvanic corrosion of the AZ31B compared to the untreated rivet in preliminary testing
8:20 AM
The Effect of Mg added Al-Si Coating on the Corrosion of Hot-stamped Boron Steels: Changkyu Kim1; Seongkoo Cho2; Wonseog Yang3; Homero Castaneda1; 1Texas A&M University; 2Lawrence Livermore National Laboratory; 3Hyundai Steel Corportation
The demands for light-weight vehicles to be equipped with Ultra-High-Strength-Steel (UHSS) has been globally increased in past decades by enhanced safety and environmental regulations in the automotive industry and the field of hot-stamped steel (22MnB5) has received much attention for its various advantages. In this work, the introduction of 2A group component into AlSi coating system has been characterized to improve corrosion resistance where the conventional AlSi system could not address well. Specifically, 0.1/0.5% of Mg was added into the AlSi coating during the hot dip-coating prior to the hot stamping. To characterize the coating before and after the hot stamping process that performed at 930°C for 5 minutes, SEM,EDS,XRD, and XPS were utilized to see morphology and chemical compound changes before/after the hot stamping and corrosion testing. It is anticipated such improvement of the coating with 2A group element can contribute pioneering new generation coating for automotive industry.
8:40 AM
Advanced Composite Coating for Carbon Steel Corrosion Prevention: Fangming Xiang1; Christy Koerner1; David Hopkinson1; Margaret Ziomek-Moroz1; 1National Energy Technology Laboratory
In natural gas transmission pipelines, conventional coatings based on epoxy, paint, and polyethylene are widely used to prevent carbon steel corrosion due to reasonable barrier property and high chemical stability. However, these conventional coatings are not impermeable to corrosive species and may not be tightly bonded to the steel surface, leading to underfilm corrosion. A 60-nm-thick layer-by-layer (LbL) assembly containing a polymer (polyethylenimine) and a corrosion inhibitor (tannic acid) can completely prevent water-induced corrosion and significantly enhance surface adhesion through coordination and ionic bonding, but it tends to swell and subsequently lose its corrosion resistance when exposed to high concentrations of CO2 and NaCl. By using a conventional coating as the top layer and a LbL assembly as the bottom layer, we have created a composite coating that combines the complementary advantages of both constituent layers, demonstrating a synergistic approach for maximizing the corrosion resistance of anti-corrosion coatings.
9:00 AM
Enhancing Corrosion Resistance of Steel Substrates with Reduced Graphene Oxide Reinforced Polymer Composite Coatings: Recep Onler1; Samet Akturk1; Erdal Topac2; Ercan Ozdemir1; Ahmet Oktem1; Ongun Saban1; 1Gebze Technical University; 2Hazerfen Kimya Malzeme ve Enerji Teknolojileri Sanayi Ticaret A.Ş.
Due to their superior chemical and mechanical properties, graphene and graphene oxide are recently emerged filler materials in various coating systems to improve corrosion resistance and mechanical durability. In this study, corrosion resistance of a multilayer coating on a mild steel substrate is investigated via potentiodynamic polarization. To obtain the multilayer coating system, samples are first galvanized and passivized. Thin layers of two different primers are applied on the passivization layer followed by a polyamide 12 topcoat. The effects of graphene oxide filler on both primers and topcoat are experimentally investigated with 0.5 to 1 %wt. filler rates. Experimental corrosion rates for coated specimens are examined in aqueous NaCl solution by the Tafel method. It is shown that the corrosion rates are reduced at least 10 times even with the 0.5 % wt addition of RGO as a filler material in the multilayer coating system.