Analytic Mathematical Models for Fracture Growth Due to Hydrogen Embrittlement

Abstract

Abstract: Analytic Mathematical Models for Fracture Growth Due to Hydrogen Embrittlement.

Dr. A. Balueva, J. Magaña, 2019

Prepared for ARC, 2019.

Hydrogen Embrittlement, or Hydrogen Induced Cracking (HIC), is a physical phenomenon that affects structural steel in pipelines, and other applications, which are subject tothe diffusion of gaseous hydrogen. Over the last two decades, a great amount of research has focused on understanding the basic mechanisms that govern HIC. The ability to reliably predict the growth-rate of a Hydrogen-driven fracture is key to developing safe and efficient practices in the natural gas industry and other operations in which HIC is a common occurance.

The aim of our research is to propose a mathematical model that predicts the size of the fracture opening as a function of time. We derive this model analytically, first modeled under ideal gas, and again under non-ideal gas. A physical justification is provided for our model. With our resultant equations, we calculate the expected crack-growth for a real-life example, using known data. We conclude with a discussion about crack-propagation under very high pressures, limitations for the model, and generalization for the future.