Estimation of hardening depth of workpiece KC.18- DP.93

U ovom diplomskom radu zadatak je bio procijeniti dubinu prokaljivanja strojnog dijela KC.18DP.93. Rad je podijeljen u dva dijela. U prvom, teoretskom dijelu, općenito je opisan postupak toplinske obrade i utjecaj iste na promjene svojstava i mikrostrukture čelika. Nadalje, opisan je i utjecaj legirnih elemenata na svojstva i promjene mikrostrukture čelika. Objašnjava se metoda toplinske obrade kaljenjem te pojmovi poput prokaljivosti i neke metode procjene prokaljivosti. Na samom kraju teoretskog dijela rada opisane su metode ispitivanja tvrdoće strojnog dijela. U drugom, praktičnom dijelu rada navedene su karakteristike čelika KC.18-DP.93, oprema i postupak provođenja Jominyjeve metode ispitivanja prokaljivosti. Na temelju rezultata Jominyjeva pokusa konstruirana je Jominyjeva krivulja. Craft-Lamontovim dijagramima dobiven je tok tvrdoće po poprečnom presjeku strojnog dijela KC.18-DP.93.In this graduate thesis the goal was to estimate hardening depth of workpiece KC.18-DP.93. The thesis is divided into two parts. In the first, theoretical part, the procedure of heat treatment and its effect on properties alteration and microstructure of steel was generally described. Further on, the effect of alloying elements on properties and microstructure's alteration of steel is also described. The method of heat treatment through hardening is explained, as are terms like hardenability and some hardenability estimating methods. At the very end of the theoretical part of the thesis, hardness testing methods of workpiece are described. In the second, practical part of the thesis, characteristics of steel KC.18-DP.93, equipment, and the procedure of implementating Jominy's hardenability testing methods are listed. Based on the Jominy test results, Jominy's curve is constructed. Hardness curve of cross section of workpiece KC.18-DP.93 was obtained using Craft-Lamonts diagrams