Called KCSM40, the company has taken the toughness of its most popular milling grades KC725M and X500, and increased the thermal crack resistance and wear resistance that will enable customers to machine at higher cutting speeds, without sacrificing that original toughness.
The grade has an advance cobalt binder that provides exceptional thermal fatigue resistance, without sacrificing the toughness customers have experienced with KC725M or X500. In addition, Kennametal’s proprietary AlTiN/TiN coating enhances the wear resistance at the cutting edge.
The target cutting speed for KCSM40 in Ti6Al4V was 53 m/min a 327 cm3/min metal removal rate for 60 minutes. Not only does KCSM40 achieve this, but has also offered milling titanium at speeds up to 85 m/min at a lower radial depth of cut.
Says Scott Etling, director of global product management for Indexable Milling at Kennametal: “At higher radial engagements, the insert is cutting the material for longer time which creates more heat at the cutting zone. The heat will not go into the titanium chips, like when milling steels, so controlling the heat is critical. Lower cutter speeds at higher radial engagements is a good practice. At lower radial engagements, higher cutting speeds can be achieved.”
Recent internal testing with the new Harvi Ultra helical milling platform achieved over 100 minutes of tool life running at 47 m/min with a 0.12 mm/tooth chip load. The radial depth of cut was 25 mm and the axial depth of cut was 76 mm. States Etling: “The edge condition on the KCSM40 grade still looked great. And we are getting many other fantastic results. In one face-milling operation on a hardened steel wear plate, the number of passes was reduced from 234 to just 22. Needless to say, I am very excited for Kennametal and the value KCSM40 will bring to our customers.”
Edge condition looks good - recent internal testing with the new Harvi Ultra helical milling platform achieved over 100 minutes of tool life running at 47 m/min with a 0.12 mm/tooth chip load. The radial depth of cut was 25 mm and the axial depth of cut was 76 mm
Although developed with Ti6Al4V in mind, KCSM40 will be a top performer in other high temperature/heat resistant materials, the company adds, citing aero structure and engine components, energy sector items such as turbine blades and parts made from duplex stainless steels, plus transportation sector parts such as turbo chargers.
