High alloyed steel; inclusion; fracture (initiation, propagation); LiMaRC - Liège Materials Research Center
Abstract :
[en] every commercial steel product in varying amounts. Since inclusions significantly influence
properties and behaviour of materials and at the same time give indications on the quality of the steel, it is quite interesting to precise their nature and their origin.
In this paper concerning a project involved in the COST 517 framework, studied alloys are high alloy steels. The raw materials were obtained from the conventionally electrical cast ingot and the Electro Slag Refining processes.
The purpose is to compare various inclusions produced by these different processes and their effect on the mechanical properties. The raw material because of the melting processes themselves, leads to a product with a good to a great cleanliness, and tiny inclusions, which are haphazardly distributed. The actual ASTM E45 chart seems to be inappropriate, as the inclusions founded are too small in size. Therefore, we manage to develop a specific procedure for the study of such inclusions. The different types of inclusions encountered are oxides, titanium nitrides, and manganese sulphides.
Studying the effect on mechanical properties, oxides often seem to initiate fatigue fracture.
