Steel turning inserts cemented carbides have a binder phase consisting of cobalt (Co). However, in recent years a study from the United States National Toxicity Program (NTP) found that cobalt powder is carcinogenic upon inhalation. The European Union's REACH have therefore also classified cobalt powder as carcinogenic upon inhalation. The worldwide search to find a replacement has therefore lately intensified. It is important that the alternative binder phase has no negative effects on the properties of the insert. In this thesis the adhesion between a multilayer ceramic chemical vapor deposition (CVD) coating and a cemented carbide with the alternative binder phases consisting of iron (Fe), nickel (Ni) and cobalt (Co) has been studied. First of all, the fracture surfaces showed that the CVD coating was able to grow on all cemented carbides, regardless of which binder phase. To evaluate the adhesion, scratch tests were performed on all samples. The results from the scratch tests were not as expected. No chipping of the coating down to the cemented carbide occurred on any of the samples and the samples with the hardest cemented carbide did not get the highest critical load, which it should according to the literature if all other parameters were the same. Instead the sample with the binder phase consisting of 73 wt% iron and 27 wt% nickel had the highest critical load. This is thought to be due to that during the scratch test the binder phase in this cemented carbide would most likely transform into deformation martensite.

In this thesis, drill bit buttons with cobalt, nickel and iron binders in different compositions have been tested against granite and sandstone and the wear and friction have been measured. Furthermore, the wear and degradation of the buttons have been categorized. Buttons with cobalt binder were tested against granite and sandstone and buttons with alternative binders (Ni, Fe, Co) were tested against granite. Cobalt buttons were used as a reference and the wear and friction of the alternative binders was compared to the reference. The amount of worn rock was also measured. Furthermore, post treated drill bit buttons with a composition of Fe-Ni-Co were compared to buttons with the same composition that had not been post treated The results show that buttons with an alternative composition of Fe-Co-Ni and Fe- Ni wears less than the cobalt reference. The post treatment process does not decrease the wear of the drill bit but lowers the deviation from the mean wear. The amount of worn rock does not differ between the samples except for between the post treated and not post treated buttons with a composition of Fe-Ni-Co. The post treated buttons produces more rock debris than the not post treated. No apparent difference could be seen on the surface of the tested buttons after the test. However, composition specific cracks could be found underneath the surface of the samples. EDS-analysis showed signals of oxygen inside of all of the investigated cracks. For some compositions at depths of 20 micrometers. The curves of friction shows similar appearance but the values of the coefficient of friction differs. No apparent correlation was found between the wear and friction of the samples. Furthermore, no apparent correlation was found between the hardness and the wear of the buttons.