Experimental study on cryogenic milling performance of SiC_p/Al composites with liquid nitrogen

Abstract

Silicon carbide particulate-reinforced aluminum (SiC_p/Al) composites is one of the typical difficult-to-cut materials, which are not suitable well for traditional machining any more. In order to explore new processing technology and verify its feasibility, this paper discussed the effects of cryogenic assisted milling with liquid nitrogen (LN₂) coolant on the machinability of SiC_p/Al composites. The effects of cryogenic milling were also compared with that of conventional dry milling. The results showed that cryogenic milling of 20% SiC_p/Al composites would increase the surface hardness of the material, causing 15% higher amount of cutting force in cryogenic milling as compared to dry milling. In addition, there were serious tool feed marks on the machined surface under cryogenic condition because of the secondary cutting mechanism, which resulted in high surface roughness and poor surface quality. Overall, 46.73% higher roughness R_a and 31.53% roughness R_z were seen for cryogenic milling in comparison with dry milling technique respectively. The dish angle of milling tool and processing environment plays important roles in machined surface. Chip brittleness increased and short arc chips were formed in cryogenic milling. It was suggested that milling SiC_p/Al composites under cryogenic condition had negative effects on the machinability of the material.

KEYWORDS:

• SiC_p/Al composites
• cryogenic milling
• cutting force
• dish angle
• liquid nitrogen
• surface topography

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China under (grant nos. 51605161, 51775184 and 51905169).