Effect of Microstructure on Hydrogen Diffusion in Weld and API X52 Pipeline Steel Base Metals under Cathodic Protection

<div>Effective diffusion coefficient of hydrogen in API X52 steel using different methods: (a)<i> Time Lag</i>, <span class="nowrap"><svg height="10.8649pt" id="M24" style="vertical-align:-3.18155pt" version="1.1" viewbox="-0.0498162 -7.68335 10.1364 10.8649" width="10.1364pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M329 37L319 72C301 64 285 60 268 60C248 60 212 69 212 147V394H304C320 402 321 431 310 442H212V586L198 593L84 515V442H44L16 406L21 394H84V114C84 24 130 -12 207 -12C214 -12 230 -8 247 -1L329 37Z" id="g13-114"></path></g><g transform="matrix(.0091,0,0,-0.0091,4.407,3.132)"><path d="M514 185C496 134 477 102 459 82C435 55 399 49 360 49C330 49 304 50 285 58C265 66 261 85 261 131V512C261 595 269 601 347 608V650H37V608C114 601 124 595 124 512V138C124 55 114 49 28 42V0H519C528 27 549 127 557 173L514 185Z" id="g22-74"></path></g></svg>,</span> and<i> Breakthrough</i>, <span class="nowrap"><svg height="10.8649pt" id="M25" style="vertical-align:-3.18155pt" version="1.1" viewbox="-0.0498162 -7.68335 10.9493 10.8649" width="10.9493pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M329 37L319 72C301 64 285 60 268 60C248 60 212 69 212 147V394H304C320 402 321 431 310 442H212V586L198 593L84 515V442H44L16 406L21 394H84V114C84 24 130 -12 207 -12C214 -12 230 -8 247 -1L329 37Z" id="g13-114"></path></g><g transform="matrix(.0091,0,0,-0.0091,4.407,3.132)"><path d="M415 353C483 366 567 404 567 500C567 550 544 592 507 615C467 641 415 650 341 650H45V608C116 601 125 594 125 512V138C125 55 116 49 38 42V0H297C380 0 457 15 508 43C566 74 603 127 603 194C603 290 527 335 415 348V353ZM259 366V549C259 568 261 583 268 590C274 597 290 603 314 603C368 603 422 571 422 482C422 399 375 366 283 366H259ZM259 320H280C391 320 453 275 453 183C453 87 389 48 332 47C278 46 259 68 259 138V320Z" id="g22-64"></path></g></svg>;</span> (b)<i> Fourier</i>.</div>

International Journal of Corrosion

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Figure 15

Figure 15: Effect of Microstructure on Hydrogen Diffusion in Weld and API X52 Pipeline Steel Base Metals under Cathodic Protection 