Work of: M. Monnoyer, B. Corlu, T. Machado Amorim, L. Dosdat, C. Dieu Interest of new generation ZnAl3.7Mg3.0 (Magnelis ® ) coatings for the Energy and Construction Market Ir D. Parein Work of: M. Monnoyer, B. Corlu, T. Machado Amorim, L. Dosdat, C. Dieu

ArcelorMittal in a nutshell What is ZnAlMg coating: Magnelis ? Exceptional Properties Corrosion resistance – specific behaviour Self healing effect Abrasion resistance Applications

Leader in North America Leader in Latin America* ArcelorMittal Worldwide 85 Mt of Steel ArcelorMittal is the world's leading steel and mining company 209,000 employees in more than 60 countries. An industrial presence in 19 countries Value geographical breadth/ product diversity/ raw materials security Leader in all major global steel markets Automotive Construction Household appliances Packaging Energy Wordclass R&D and technology Leader in North America Leader in Latin America* No 1 in Europe Major producer in the CIS Leader in Africa ArcelorMittal Others Information on the graph updated by Adina Sinea (March 2013) 2

ArcelorMittal for Energy from steel to solutions...

~ 4 mmt participation to energy markets … Plate for oil and refined products rail car transport Plate for oil tankers Steel products for coal, gas power stations, nuclear, electricity transmission ... Slabs for plate production for LSAW pipe HRC for spiral welded pipe Plate for LSAW pipe Spiral welded pipe Seamless pipe Tube and plate for oil refining Plate for CTL/GTL Plate for storage tanks Plate for gas treatment Plate and krybar for LNG Blooms for compressed natural gas Clad plate for subsea flowlines and risers Wire products for flexible risers Plate for slurry pipes (oil sands) Blocks for pumps and blow-out preventers Slabs Plate Tubular products Sections and Beams Wire rod Slabs for HRC for welded tubes HRC for welded tubes Welded tubes Seamless Tubes … strategic choice to further develop

broad energy product portfolio … Seamless OCTG API 5CT, EN, NF, DIN, CSN,UNI Hunting premium  23/8” – 16” up to Q125 Seamless Pipe API 5L, ASTM, ASME, EN  0.5” – 20” up to X70 Spiral Line Pipe EN, API, DIN, CSN, GOST  123/4” – 56” up to X70 Longitudinal Welded Pipe API 5L, ASTM, DIN, EN  4,5” – 56” up to X65 Coating Services Varnish, lacquer, enamel, poly- ethylene, cement- plastic, bitumen, cement mortar, epoxy tubular product family Structural Steels non-alloy fine grain offshore proprietary HISTAR Fritenar + offshore Wire including flat wire for flexible pipe Rebar including Krybar for cryogenic applications long carbon product family Construction plate Plate for Offshore and Line Pipe Pre-qualified 2Y 60 up to 3” Shipbuilding plate Specialty plate Stainless & clad steels Cryogenic steels Pressure vessel steels Special formats Jack-up rig leg components Blocks for blow-out preventers plate product family HRC for Line Pipe HRC for OCTG Special flat carbon products Magnelis: corrosion resistance fire resistant steels light flat carbon product family … covering all steel needs for energy-related projects

unmatched global reach … 230.000 employees presence in 60 countries 5 continents 2013 steel shipments 84 million tons AM Projects Oil&Gas] flat carbon steel mill plate mill beams & sections pipe & tube R&D centre project centre sales office … we feel comfortable serving you any place in the world

MAGNELIS®| Exceptional Corrosion resistance

Heavy gauges applications in Oil & Gas and Construction Market│ Major Corrosion issue Structural parts often submitted to high level of corrosion stress due to direct exposure to: Aggressive atmosphere chemistry (salt, offshore, industrial or animal pollution…) Exposure to sand abrasion Soil burying Water immersion or dripping Concrete immersion … Thick gauge (2 to 6 mm) = increased risk of cut edge corrosion Thinner gauge ( < 2mm ) (use of High Strenght Steels) = increased risk of parts perforation  Need for high performance or additional corrosion protection means M. Monnoyer, B. Corlu, T. Machado Amorim, L. Dosdat, C. Dieu – Galvatech 2015 8

Heavy gauges applications in Oil & Gas and Construction Market│ How to improve life time ? High performance or additional corrosion protection means Thick standard Zn-based coatings 600gr/m² or more Alternative Al-based coatings (Aluzinc, Aluminized type 2…) Batch galvanizing Drawbacks: high cost, impact on in-use properties (profiling, welding) Alternative substitution: thin, high corrosion resistant ZnMgAl (Magnelis) coating? Zn – 3.7Al – 3.0Mg 9

Corrosion Protection Mechanism: Lower Oxygen Reduction At the initial stages of corrosion process, metallic coating consumption is governed by oxygen reduction rate Erest ZnMgAl Erest GI Coating dissolution ZnMgAl GI Polarisation curves (5%NaCl – pH=7) Oxygen reduction Jcorr (µA/cm2) GI ~20 ZnMgAl ~10 ZnAlMg allows decreasing oxygen reduction rate by a factor 2 compared to standard HDG-Zn 10

Corrosion Protection Mechanism: Inhibiting Corrosion Products When the coating corrodes, corrosion resistance is closely linked to the inhibiting properties of corrosion products that precipitate both on steel and coating surfaces Initial state Coating Steel Environment O2 OH- Mn+ e- Advanced state Coating Steel Environment Corrosion products O2 OH- Mn+ Mn+ (Zn2+/Mg2+/Al3+) + CO32- / Cl- / OH- / SO42- More compact and stable the corrosion product layer is, more important is the hindering effect on oxygen reduction June 2nd, 2015 11

LDH ≥ ZHC = ZHS > HZ > ZC > ZnO Corrosion Protection Mechanism: Compact corrosion products Main Zn and ZnMgAl corrosion products formed in cyclic corrosion tests and in field exposure Zinc oxide: ZnO Zinc carbonate (ZC): ZnCO3 Hydrozincite (HZ): Zn5(CO3)2(OH)6) Simonkolleite (ZHC): Zn5(OH)8Cl2 / Zinc Hydroxide sulphate (ZHS) Zn4SO4(OH)6 Layered Double Hydroxide (LDH): Zn0.61Al0.39(OH)2(CO3)0,195.xH2O ZHS ZHC HZ ZC ZnO Corrosion inhibition LDH ≥ ZHC = ZHS > HZ > ZC > ZnO High compactness  zinc basic salts Low compactness  ZnCO3 and ZnO Inhibition power of corrosion products is in direct relation with their compactness June 2nd, 2015 3% Mg is minimal needed cfr study at Tsukuba University /Japan- March 2010 12

Corrosion Protection Mechanism: Corrosion Products of Magnelis (ZnAlMg) Alloying elements present in ZnAlMg coating will contribute to the precipitation of compact and stable corrosion products Samples analyzed after 2 years of exposure in Brest (Marine environment) Zn-Al LDH ZHS ZHC HZ ZnO ZnAlMg + ++ - HDG-Zn +++ On standard HDG-Zn, poor protective corrosion products are detected in high amount Important quantity of ZnO and HZ, presence of ZHS and ZHC On ZnAlMg, major presence of protective corrosion products ZHC/ZHS and LDH, low amount of HZ, no ZnO 13

Corrosion Protection Mechanism: Corrosion Products in real corrosion simulation Compact Simonkolleite is observed on ZM surface after 10 VDA cycles Porous Mg carbonate EDS: Mg>>Zn , C, O Compact Simonkolleite EDS: Zn>>Mg, Cl, O Simonkolleite is the protective corrosion product Mg carbonate forms but is not protective

Corrosion Protection Mechanism: Role of Al and Mg 4/28/2017 4/28/2017 Corrosion Protection Mechanism: Role of Al and Mg The role of Mg2+ ions is to stabilize the protective Zn-corrosion products (ZHC, ZHS), avoiding their transformation into ZnO The role of Al is the formation of protective and stable LDH corrosion product The strong barrier effect of corrosion products formed on ZnMgAl is clearly shown from electrochemical trials in controlled potential conditions 15 15

Magnelis outperforms standard pre and post galvanized materials Exceptional Corrosion Resistance In a Salt Spray Test Magnelis (20µ) compared with pre galvanized (20µ) Magnelis (20µ) compared with post galvanized (85µ) Galvanised Magnelis Salt Spray test Z after 6 weeks Magnelis after 34 weeks Magnelis outperforms standard pre and post galvanized materials

Exceptional Corrosion Resistance: In a Marine environment Sea Test results of the French institute of corrosion Samples Brest Test Area: Brest (FR), C5M environment (marine, 2 meters from the sea) Similar test done in Florida (US) (C4/C5 environment) with same results Also in Marine environments Galvanized steel corrodes 3 times faster than Magnelis® Confidential

Improved Cut Edge protection: Mechanism Al3+ Environment Mg2+ Zn2+ Current Density (J) Oxygen reduction -1.05 Coating dissolution Hydrogen reduction E (V/SCE) Steel dissolution OH- O2 e- Steel Coating On cut edges, coating dissolves preferentially to protect steel Corrosion products precipitation on cut edges  self-healing mechanism 18

Self healing effect observed in outdoor exposure after 9 months Improved Cut Edge protection: Assesment in Field exposure Red rust evolution observed on ZnAl3.7Mg3 coated samples with varying thicknesses during 9 months outdoor exposure on marine site (French Corrosion Institute in Brest, Marine environment) Evaluation by computer assisted image analysis Steel thickness=4mm Steel thickness=5mm Steel thickness=5,5mm 1month 3months 6months 9months Coating thickness: 25µm Self healing effect observed in outdoor exposure after 9 months 19

Coating thickness: 20µm, steel thickness: 2mm Improved Cut Edge protection: Life time extension of perforated steels Red rust evolution observed on ZnAl3.7Mg3 coated perforated samples compared to standard HDG-Zn and HDG-AlZn during 5 years outdoor exposure on marine site (French Corrosion Institute in Brest, Marine environment) - Evaluation by computer assisted image analysis Coating thickness: 20µm, steel thickness: 2mm Es after 5 yeatrs Self-healing Comparison Magnelis (ZnAl3.7Mg3 ) >4 years HDG-Zn  1 year HDG-AlZn  no self healing effect Results after 5 years: 20

MAGNELIS®| Sand abrasion resistance

Coating hardness has a direct impact on the abrasive wear resistance Abrasion resistance: Microhardness as reference for abrasion resistance Coating hardness has a direct impact on the abrasive wear resistance Material HV Galva 64 Galfan 69 Aluzinc 129 Magnelis® 141 Batch galva: Outer Zn layer of batch Intermetallic layers 70 More than 179 Magnelis® hardness is much higher compared to standard zinc coatings and Zn layers of batch galva

Abrasion & Corrosion resistance: Real outdoor exposure First desert field : Dubai, collaboration with the French Corrosion Institute (Worldcoat project) 23

Abrasion & Corrosion resistance: First results of real exposure in Dubai First set-up (Magnelis & HDG) exposed since 2 years Second set-up (Magnelis & batch galva) exposed since 1 year 24

Magnelis: Broad usage Applications: Magnelis: Broad usage Outstanding corrosion resistance Self healing effect assuring protection of the edges Cost effective alternative for aluminium, stainless and batch galva Thickness available from 0.45 mm until 6 mm Very good corrosion protection in soil Structures for solar structures Storage tanks – Silo’s Decks for parking lots, Sound isolation wall panels Civil engineering & Public Works … Profiles, Tubes Structural material, Cladding, Cable trays, Expanded metal, Concrete moulds, Building & Construction

Conclusions: Magnelis offers… Improved corrosion resistance (3% of Magnesium) Edges protection thanks to the Self healing effect Very good abrasion resistance Excellent resistance in soil and concrete Excellent adhesion for post painted Excellent formability Environmental friendly coating A breakthrough material for tubes