Medium Carbon Steel Surface Hardening by Vacuum Arc Cleaning of Oxide Layers

Cathode Spot Behavior Variation in Oxide Layer Removal Caused by Potassium Hydroxide Pre-treatment

“…However, our previous report described that the heat-affected layer near the VAC-treated surface thinned when the KOH aqueous solution was applied, which seems to be related to the present obtained result described as (2). 13) Our future work will include more detailed investigations into cathode spot energy density and the treated surface state.…”

“…[8][9][10][11] Especially, it has been recognized that the work function change of the oxide layer surface causes different behavior of cathode spots and engenders decreases in both the roughness and heat-affected layer thickness of the cleaned metal surfaces when an aqueous solution of potassium hydroxide (KOH) is applied to the oxide layer surface before VAC. 12,13) Although the detailed mechanism has not been unveiled yet, this phenomenon must be a key to understanding the roles of the cathode spots in VAC. For this study, KOH aqueous solutions of various concentrations were applied to change the work function of the oxide layer surface before the VAC.…”