Structural transformation of steel induced by application of oxyfuel gas cutting using acetylene and propane/butane mixture

In metal processing industry oxyfuel gas cutting is a widespread and common procedure for cutting steel. This procedure is usually the first operation in material preparation whose objective is producing cutting surface ready for the next operation, usually welding. Experimental part of this study deals with influence of oxyfuel gas cutting with use of acetylene and propane-butane mixture on microstructure and hardness of low- alloyed high-strength steel S960 QL. Significant differences in microstructure and hardness of cutting surfaces as well as heat-affected zone size have been determined for surfaces created by cutting with acetylene and those created by oxyfuel-cutting with use of propane-butane mixture. Decarburization along the edges of cutting surface has also been established regardless of type of gas used during cutting or of the fact that preheating was conducted.