Thermal effects on tribological behaviors of polycrystalline cubic boron nitride

Tribological Behaviors of Polycrystalline Cubic Boron Nitride Sliding against Bearing Steel in Vacuum Conditions

“…CoFs are mostly stable after 13 min, and they proceed to a steady-state. Figure 2b shows that the stable CoF of the tribopair decreases firstly and then increases with an increase in loads from 2 N to 15 N. The highest average CoF is 1.19 at 2 N. In addition, when the load is 10 N, the average CoF reaches the lowest value of 0.64, which is similar to CoF in air [5]. The wear rate of counterpart balls decreases with the increase in loads, showing 14.2 × 10 −12 mm 3 /N mm at 2 N and 7.6 × 10 −12 mm 3 /N mm at 15 N, as shown in Figure 2c.…”

“…Thus, the soft and ductile metal adheres on the surface of PcBN. Compared with the tribological behaviors in air, the adhesive wear in vacuum is more serious [5]. The results manifest that metal materials are more likely to adhere to the PcBN in vacuum and high load conditions.…”

“…Hence, the loads exhibit an obvious influence on the friction and wear rate of PcBN-AISI 52100 tribopair. Furthermore, compared with the wear rate in air (10 −8 mm 3 /N mm in order), the wear rate in vacuum is much lower [5]. It may come from complex serious adhesion.…”

“…The PcBN tool shows the advantages of high hardness, excellent wear resistance, high thermal conductivity, and chemical inertness [1][2][3]. It is a typical green manufacturing high-speed cutting tool and has an important application prospect in the field of space manufacturing technology [4][5][6][7]. It is proved that the friction and wear behaviors of tools and metals can be affected by the complex vacuum environment, resulting in the elusive failure modes of materials [8][9][10].…”