1. COMPOSITION OF STAINLESS STEELS TESTED Chemical Analysis (% weight)PRENW CrNiMoCuWN(1) 0,0525 0,1734 0,2541 0,28 0,2043 0,50,4856 0,0738 17,2 22 25 24,9 19,9 24,5 26,7 24,5 2,6 3,2 3,6 3,8 6,0 7,3 3,4 4,7 1,5 0,7 0,4 0,9 1,50,4054 316L 31803 32520 32750 312 54 32654 08028 08932 08926 Trade Name UR52N+ SAF2507 254SMO 654SMO SAN 28 URB66 URB2620 12,6 5,5 6,3 6,9 17,8 21,8 30,3 22 24,76,30,80,1943 UNS SAF2205 AISI PRENW : Cr + 3.3 Mo +1.6 W + 16 N 2

2. PITTING CORROSION RESISTANCE NaCl 30 g/l - ASTM G61 URB66 316L N08926 2030405060708090100 200 400 600 800 1000 0 Temperature, °C Pitting Potential, mV/SCE N06 622 304L UR45N S 31726 32 520 904L

3. LONG TERM IMMERSION TESTING in NATURAL SEA WATER (Crevice Corrosion)

4. REST POTENTIAL OF MCW SAMPLES in MEDITERRANEAN SEA 100 200 0 - Crevice Corrosion 32550, 08926, URB66 :No Crevice Cor 08904 - 400 0 +400 Rest Potential, mV/Ag-AgCl 31803 31603 30403 Time, Days MCW : multi crevice washers

5. EFFECT OF CLIMATIC CONDITIONS PRENW > 40 :UR52N+, URB26, URB66 (MCW samples): no Crevice Corrosion +400 0 -400 1002000 Rest Potential, mV/Ag-AgCl Time, days Mediterranean Sea, F North Sea, N Atlantic Sea, F 316L Crevice PREN > 40 no corrosion

6. CREVICE CORROSION in NATURAL SEA WATER Steel GCBKT ItalyFranceFranceSwedenNorway 316L5/55/50/40/44/4 31803++++0/5+ 32520++0/50/5+ 327500/4+0/5++ 31254++0/50/50/5 32654+0/50/5+0/4 08028+++0/5+ 089260/50/50/5+0/5 +/++ one/several depassivated area, no weight loss 5/5 crevice corrosion on 5 coupons out of 5 Winter + Summer immersion tests, 3000 hours each

7. MATERIAL SELECTION FOR SEAWATER SERVICE Free Cl2 (ppm) 00.510 10 10 1 10 20 T(°C) 30 40 TITANIUM UR B66 S31266 UR B66 - S31266 URB26/08926 UR 52N +/ S32 520 Stagnant Flange with Washer (1) > 1 m/s Threaded Joint (2) No fitting nor Crevice geometryCrevice Geometry If some fretting or wear is involved, the material selection has to be adapted (please, contact corrosion specialists) UR B26/N08926 or UR 52N +/ S32520 UR 45N - S31803 S 32 205 316L or UR 45N UR B26/N08926 or UR 52N +/ S32 520 Water velocity (1) (2)