Multi-component boron coatings on low carbon steel AISI 1018

LIST OF FIGURES
Figure
Page
2.1 The saw-tooth structure of boride layers with the exterior phase of FeB and the 6
interior phase of Fe2B on AISI 1018
2.2 The effect of steel composition on the morphology and thickness of the boride
layer 16
2.3 The effect of percent alloying elements on the boride layer thickness 17
2.4 The effect of steel compositions (nominal values in wt. %) on wear resistance
under abrasive wear (dv = thickness of the boride layer); test conditions: DP-U
grinding tester, SiC paper 220, testing time 6 minutes 25
2.5 The comparison of wear resistance between <strong>boron</strong>ized steels and non-<strong>boron</strong>ized
steel 25
2.6 The comparison of corrosion resistance between <strong>boron</strong>ized steels and non<strong>boron</strong>ized
steels 26
2.7 The hardness value for various materials and surface treatments 29
3.1 The experimental flow chart 45
3.2 The illustration of all procedures taken in the borozning heat treatment 49
3.3 The illustration of the grinding and polishing procedures to prepare a specimen
to be tested for microstructure and microhardness 51
3.4 The illustration of observations, a) the illustration of observing images taken on
one side of the coated specimen and b) the image taken by the DIC microscope
to show the hardness of the surface 53
3.5 The equipment setting for corrosion testing (using the continuous weighting
method) 57
4.1 The morphology images of boride coating (in the B-Fe system) on low carbon
steel AISI 1018 a) under bright field, b) under differential interface contrast
(DIC), and c) the distribution of coating thickness 70
4.2 The XRD pattern (refined with the Rietveld Refinement) of the boride coating
in the <strong>boron</strong>-iron (B-Fe) system 72
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