Influence of boron on microstructure properties of 13% chromium white irons

In this paper, the results of the examinations of the influence of boron on microstructure properties of 13% Cr–2.3% C high‐chromium white irons are presented. The following quantities of boron were used: 0.26%, 0.39% and 0.59%. The results that confirm significant influence of boron on the structure of chromium white iron were obtained by means of optical microscopy, scanning electron microscopy, X‐ray diffraction and quantitative metallographic analysis. It is demonstrated that boron has strong carbide‐forming effect. With the increase of boron concentration in the alloy, the volume fraction of primary phase decreases and the volume fraction of eutectic carbide phase increases at the same time. It is also demonstrated that in the presence of boron the type of prevailing carbide is changed, that boron influences the structure phases morphology, and that boron supports the transformation of austenite into martensite.