A nanomechanical test instrument for investigation of combined loading and electrochemical effects on stress corrosion cracking in high performance structural alloys

Abstract

According to the recent LMI Cost of Corrosion Study 1, the annual cost of corrosion for U.S.Navy Ships and Aviation in 2010 was a combined ~$5.75billion. More than 80% of structuralfailures were due to combined environmental and mechanical loading. This translates into, onaverage, 20% down time due to unscheduled maintenance every year 2. The majority offailure/maintenance issues result from electrochemical effects coupled with mechanical loading.To date, the traditional approach to understanding the degradation behavior of these structuralmaterials and joints has provided a somewhat myopic view because the experimental andmodeling behavior analyses are restricted to a specific loading scenario instead of structural lifeprediction methodologies within a combined loading framework. Hence, understanding thecombined effects of environmental and mechanical loading in naval structural elements and howthe combination initiates corrosion would, in addition to improving upon predictive capability,undoubtedly aid in the improvement of mission readiness.Towards this, we propose to purchase a state-of-the-art nanomechanical test instrument tostudy combined loading and electrochemical effects on early stress corrosion cracking behaviorin high performance structural alloys. Thus, in conjunction with the 4D Materials Science Centerat ASU led by Prof. Chawla, this system will provide capability to conduct stress enhancedcorrosion experiments while studying the evolution of the microstructure at the micrometerscale. Furthermore, this technique is capable of registering the onset of plasticity in extremelysmall volumes; hence, data generated using this system will be directly used to validate thecombined corrosion and mechanical simulation technique currently being developed at ASUthrough the ONR funded project (N00014-16-1-2174). We believe that the proposed system andresearch work will provide a huge leap in the fundamental understanding of local microstructuraleffects on intergranular corrosion, as well as crack tip processes during combined corrosion andmechanical loading.

Document Details

Document Type
DoD Grant Award
Publication Date
Jan 04, 2017
Source ID
N000141712027

Entities

People

  • Kiran Solanki

Organizations

  • Arizona State University
  • Office of Naval Research
  • United States Navy

Tags

Fields of Study

  • Materials science

Readers

  • Neurological Diseases/Conditions/Disorders
  • Research Science/Academic Research
  • Structural Health Monitoring of Composite Structures.