Ivan Mrkvica

Prediction of Selected Aspects of Machinability of Austenitic Stainless Steels

The development of new materials and components for the development of new materials requires cutting their research in the cutting process. Currently, the increasing technical and economic requirements for the production of components (eg, increased productivity) of machining hard materials to improve the efficiency of cutting process. Finding the causes and define the conditions for efficient cutting process stainless steel is a paper.

Study of Elastic Deformations in Hard Turning

This paper deals with study of elastic deformations after hard turning of bearing steel 100Cr6. It is well known that elastic deformation could strongly affect precision of produced parts. This aspect takes a significant role during hard turning due to poor plasticity of machined material. This study presents information about elastic deformation when turning steel of different hardness and their relations to the cutting conditions. Result of this study indicates that elastic deformations are more pronounced during turning steels of high hardness and strongly depend on cutting conditions.

Properties and comparison of PVD coatings

Razvoj i primjena novih materijala u strojarskoj praksi dovode do mnostva pitanja u odnosu na njihovu tehnolosku primjenu. Ovaj je rad usmjeren na istraživanje problema povezanih s cementiranim karbidom premazanim primjenom PVD (Physical Vapour Deposition) metode. U teorijskom dijelu rada upoznaje se PVD tehnologija nanosenja sloja i detaljnije opisuje metoda isparavanja luka. Opisuju se također materijali i vrste slojeva, njihova svojstva, moguce primjene i na kraju objasnjavaju nacela eksperimentalnih metoda primijenjenih u ispitivanju slojeva. U eksperimentalnom dijelu rada opisuju se postupci mjerenja i ispitivanja te daju rezultati ispitivanja. Adhezija i trajnost slojeva uspoređeni su na izrezanim umetcima s razlicitim PVD – premazi s nanostrukturom i nanoslojem. Ispitivanja su provedena glodanjem ugljicnog celika 1.1191 (C45) buduci da se taj celik uvelike rabi u mnogim industrijskim primjenama, a također i kao referentni material. Na kraju se ocjenjuju rezultati ispitivanja na temelju dobivenih podataka.

Contribution to Milling of Materials on Ni Base

This article deals with milling possibilities of nickel superalloy - Inconel 718. The different cemented carbides were applied for cutting process. These inserts were produced by Pramet Tools Ltd. company. This paper discusses durability of cutting inserts, the different intensity of tool wear at various cutting parameters. The most suitable cutting conditions are chosen in the scope of applied tools.

Turning of Inconel 718 by Cemented Carbides

This article deals with dry turning of nickel superalloy - Inconel 718. The different cemented carbides were applied for cutting process. These inserts were produced by Pramet Tools Ltd. company. This paper discusses durability of cutting inserts, the different intensity of tool wear at various cutting parameters. The most suitable cutting conditions are chosen in the scope of applied tools.

Comparison of Round Insert's Lifetime when Milling Inconel 718

This article focuses on the analysis of tool wear mechanisms in milling of Inconel 718. Inconel 718 is tough and highly temperature resistive material, which is used due to its excellent properties especially in aggressive corrosive medium. Machining of this alloy is still complicated. The feasibility of four inserts tested for milling of Inconel 718 has been shown in the work. Different cutting speeds and feeds were used. Experimental tests were performed in order to analyze wear patterns evolution. It was found influence of cutting conditions and type if insert in tool wear mode.

Force Load of Cutting Tool by Turning of Nickel Alloy Inconel 718 with Sintered Carbide Insert

This article presents achieved results by measuring of force load of tool by turning of nickel alloy Inconel 718 with sintered carbide inserts with the progressive chip breaker designed by Pramet Tools Ltd. Company. Authors deal with studying of force load which is exposed the cutting tool by condition, when are achieved the limit values in view of tool wear. In the end it is carried out a comparision of intensity of cutting force components for these limit conditions.

Cutting Efficiency by Drilling with Tools from Different Materials

Development of cutting tools is basic condition for rationalization of process cutting because it goes out from need of processing new constructional materials. From view of tool it takes application progressive cutting materials. Cutting tools so relevantly make for accomplishment main demand on methods of cutting; it is provision of high productivity production and attainment of desideration of finish surface. It is known, that cutting property of cutting tool is influence by many factors.

SQUARE SHAPED INSERT´S LIFETIME WHEN MILLING INCONEL 718

This article is focused on the analysis of tool wear in milling of Inconel 718. Inconel 718 is tough and highly temperature resistive material, which is used due to its excellent properties especially in aggressive corrosive environment. Machining of this alloy is still complicated. The feasibility of three inserts tested for milling of Inconel 718 has been shown in this work. Different cutting speeds and feeds were used. Experimental tests were performed in order to analyze wear evolution. It was found that cutting conditions and type of insert strongly affects tool wear mode. Surface roughness was studied as well as cutting force as a function of tool wear.

The Milling of Material Inconel 718 with Indexables Cutting Inserts from Sintered Carbide

Abstract In this document I am describing milling possibilities of nickel alloy Inconel 718. In the beginning is described use of nickel alloys in industry and division of nickel alloys. Further is described nickel alloy what I used - Inconel 718, on this material I make all my tests of machi-nability. Further chapters describe recommended cutting materials for nickel alloys milling. Cutters with exchan-geable sintered carbide blade plates were used as cutting tools company Pramet Tools s.r.o. Main goal was inve-stigate durability and wear of indexable cutting inserts for different cutting procedures. It was mainly about different combinations of used cutting speeds and feeds. The final part includes a summary of the results. The results are ones from first steps to definition of effective nickel alloy machining.