Kategóriák: Minden - corrosion - testing - boundaries

a Jack Rose 12 éve

466

Final Year Project

The project focuses on the grain boundary engineering of stainless steels and involves an extensive literature survey. Key aspects include understanding microstructure development using Electron Backscatter Diffraction (

Final Year Project

Final Year Project Grain Boundary Engineering of Stainless Steels

Sample Preparation

10% oxalic acid etch
ASTM A262 practice A
Heat Treaments
(1) no heat treatment (5% CW only) (2) 1100C / 5 min. (3) 1100C / 30 min. (4) 1100C / 180 min. (5) 1050C / 30 min. (6) 1050C / 180 min. (7) 950C / 180 min. (8) 950C / 1440 min. (9) 900C / 1440 min. (10) 850C / 1440 min.
Sectioning

Health and Safety

Testing

Mechanical Properties Testing
Microhardness

Compressive Strength

Corrosion Testing
pH-modified tetrathionate solution (K2S4O6)

Report Topics

Conlcusions
Results and Analysis
Experiemental Proceedures
Literature Survey
Grain Characterisation
Stainless Steels
Corrosion Resistance
Introduction
Grain Boundary Engineering

Literature survey

Surface effects
EBSD - microstructure development with depth from rolling
Effect of straining - 5%CW
Grain Boundaries
Brandon Criteria can theoretically predict GB misorientations
Special Boundaries - Sigma (fit)

Fit (sigma value)

determines degree of order

Grain Boundary Character Distribution
High Order Twin Boundaries
Twin Boundaries
Low Angle/High Angle GB
Coincident Site Lattice (CSL)

See Dr Mcleans structural materials book.

depending on misorientation angle - can predict grain boundary structure (wanatabe lecture)

Analyses

Image Processesing
using ASTM standard
modifying with matlab
EBSD
White Light Interferometry
SEM Examination
Grain Count
ASTM E112 - 96