Abstract
Rapid pulsed electric current sintering (PECS), TiC, TiC7N3 and Mo additions, and femtosecond (fs) laser surface modification (LSM) were used to improve the machining of automotive grey cast iron (a-GCI) using WC and NbC based cemented carbides cutting inserts. Additions of Mo and TiC as well as the use of PECS refined the grain sizes of NbC-12Ni based cermet from ∼4.6 μm to ∼1 μm, increasing the hardness (by ∼3 GPa) and wear resistance. Shark skin (S-LSM) and pyramidal (P-LSM) patterns were introduced to improve the wear and mechanical impact resistance of the cutting inserts. Face milling of a-GCI was performed at 200 m/min cutting speed (Vc), 1.0 mm depth of cut (ap), and 0.1 mm/tooth feed rate (f). The insert cutting-edge wear and damage were evaluated after every pass using optical microscopy and high angular annular dark field scanning transmission electron microscopy (HAADF-STEM). The machining performance of the cutting inserts was assessed by cutting forces, wear, and cutting insert tool life. The PECS produced NbC-10TiC-12[Ni/Mo] (wt%) P-LSM cutting insert had the lowest flank wear rate (FWR) (1.44 μm/min) after 20 min of machining. In addition, both the S-LSM and P-LSM patterns improved the cutting insert tool life of PECS produced NbC-12[Ni/Mo] (wt%) blank (B) cutting insert by ∼300 % and ∼ 900 %. Resulting in FWRs reductions of the respective insert from 21.04 μm/min after 2 min of machining to 5.97 μm/min and 1.94 μm/min after 8 min and 20 min. In general, LSM improved the NbC based cutting inserts' tool life and reduced the FWRs.
•Rapid sintering (PECS) and laser surface modification (LSM) were applied to WC and NbC cutting inserts to enhance properties.•Combining PECS and LSM improved tool life and abrasion wear resistance of NbC inserts during face-milling.•LSM enhanced the mechanical and tribological properties of cemented carbide cutting tools.•Findings contribute to advancing surface engineering techniques for high-performance wear-resistant components.•Potential applications include improved cutting tools for the automotive industry.