Electrospark coatings deposited onto an Armco iron substrate with nano- and microstructured WC–Co electrodes: Deposition process, structure, and properties

Formation of WC–Co coating by a novel technique of electrospark granules deposition

“…This untransferred material is called the "erosion products". Thus the balance between the anode mass change Δm a and the cathode mass change Δm c is broken, and The coefficient k for the electrode pair "WC-8%Co-steel" differs and has been found to be equal to 0.5-0.75 [3] or 0.1-0.3 [21]. In our case, the mass transfer coefficient lies in the range from 0.05 to 0.4.…”

“…The amount of anode material transferred to a substrate is an important characteristic because it determines the thickness of a deposited coating [3,21]. The mass changes of the cathode and granules during the EGD processing are shown in Fig.…”

“…6a). In this case, the initial tungsten carbide WC was subjected to decarburization to semi-carbide W 2 C as a result of the interaction with cobalt and iron according to the following reaction [21,22]:…”

“…6b are broad, which indicates the presence of crystal lattice deformations caused by stored defects and impurities after high-speed heating and cooling of the surface layers [23,24]. Moreover, a nano-amorphous structure (M y C ) c a n f o r m i n t h e s e c o n d i t i o n s a n d c a n e x c e e d 7 0 % i n electrospark coatings [21]. Annealing of the coatings at a temperature of 1100 K caused the recrystallization of the amorphous phase to the crystalline structure and led to the carbonization of W 2 C to WC and M 6 C phases according to the scheme [25,26] W 2 C + M y C = WC + M 6 C…”

Atomistic Simulation Study of Short Pulse Laser-Induced Generation of Crystal Defects in Metal Targets

“…The techniques used for surface modification include physical vapor deposition (PVD) [2], chemical vapor deposition (CVD) [3], coating via plasma spraying [4], electrospark deposition [5], ion implantation or sputter deposition [6], ion beam surface modification [7], and electrical discharge machining [8].…”