Investigation on fluid jet polishing of AISI H13 die steel using a single nozzle tool

Abstract

The fluid jet polishing (FJP) is an ultra-precision and non-contact type polishing process for generating high-quality surface finish in automotive dies manufactured from ductile materials like AISI H13 die steel. This paper presents a study on FJP polishing of AISI H13 die steel material using a custom-designed 3D-printed Ti6Al4V (Ti64) nozzle and silicon carbide (SiC) abrasive slurry. The study presents an effect of pressure, stand-off distance and polishing time on the surface finish while using water-based abrasive slurry mixed with water-soluble cutting oil. The Central Composite Design (CCD) method was used to develop the experimental plan. ANOVA analysis was performed to develop a regression model and find the contribution of each parameter on the percentage change in surface roughness. The regression model developed for the FJP process was validated by polishing the plate specimen of AISI H13 having [Formula: see text] average initial surface roughness with the optimized parameters; pressure of [Formula: see text], stand-off distance of [Formula: see text] and polishing time of [Formula: see text]. The optimized FJP parameters were able to generate the surface roughness of [Formula: see text] in one of the confirmation tests. The results of percentage change in surface roughness obtained from the confirmation experiments were found to be very close to the predicted results which validated the regression model developed for polishing of AISI H13 using FJP process. In addition, the optimal feed rate of 20 mm/min was used to polish [Formula: see text]plate made of AISI H13, the surface roughness was reduced from 500 nm to 130 nm in 99.2 min showing the reduction in peaks and valleys with surface improvement of 74% which results in enhanced polishing efficiency.