Microstructural changes during wear by plastic deformation of cemented carbide and cermet cutting inserts

Deformation mechanisms in a WC–Co based cemented carbide during creep

“…An increased number of binder phase lamellae at WC/WC grain boundaries was observed in the microstructures of the deformed materials, but the numbers stay low compared to what Östberg et al observed [5,11]. They suggested that the formation of binder phase lamellae was a result of grain boundary sliding during deformation.…”

“…Östberg et al studied the plastic deformation of a WC-10 vol.% Co tool caused by radial turning (facing) of a martensitic steel under severe cutting conditions (depth of cut 1 mm, feed 0.3 mm/rev, cutting speed up to 500 m/min) [5,11]. The formation of binder phase lamellae between adjacent WC grains was the most obvious change in the tool microstructure after the cutting test.…”

Mechanical Behavior of Hardmetals at High Temperature

“…Such conditions are encountered more and more frequently due to the increase in cutting speed and mass processes. Östberg and Andrén (2006) studied extensively the microstructure of WC-Co and TiCN-WC-Co cutting inserts after that plastic deformation had occurred upon high-speed turning. They found that after deformation, the binder phase had infiltrated some of the grain boundaries and formed lamellae between the hard phase grains (Figure 15).…”

“…When plotting tan(d) as a function of the temperature or frequency, a so-called IF spectrum is obtained. Figure 16 shows an IF spectrum as a function (a) (b) Figure 15 Comparison of triple points between TiCN grains (a) before deformation and (b) after deformation (Östberg & Andrén, 2006) Figure 16 Internal friction spectrum of TiMoCN-6 wt% Co measured at 1 Hz as a function of the temperature. The spectrum deconvolution is constituted of four peaks P 1 , P 2 , P 3 and P ht and of an exponential background (not shown).…”

The Contribution of Mechanical Spectroscopy to Understanding Grain Boundary Sliding

“…The presence of a phase different from that of the matrix in the grain boundary is also determinant for the deformation of composite materials such as cermets 6 . In particular, a change of the thermodynamical equilibrium under stress allows the infiltration of cobalt of WC boundaries in WC-Co based cemented carbides 7 . In metals, deformation by GBS is more rarely observed directly, even if it has been considered as a creep mechanism.…”